Download - Aortic dissection 01
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DR RAKESH ROSHAN
AORTIC DISSECTION
Review ofAorticAnatomy
Layers of Aortahellip
What is dissection of aorta
Tear in the aortic intima that directly exposes an underlying diseased medial layer to the driving force (or pulse pressure) of intraluminal blood
This blood penetrates the diseased medial layer and cleaves the media longitudinally thereby dissecting the aortic wall
Driven by persistent intraluminal pressure the dissection process extends a variable length along the aortic wall typically antegrade but sometimes retrograde from the site of the intimal tear
The blood-filled space between thedissected layers of the aortic wallbecomes the false lumen
Shear forces may lead to further tears inthe intimal flap (the inner portion of thedissected aortic wall) and produce exitsites or additional entry sites for bloodflow into the false lumen
Distention of the false lumen with bloodmay cause the intimal flap to bow intothe true lumen and thereby narrow itscaliber and distort its shape
EPIDEMIOLOGY
Uncommon but potentially catastrophic illness
Occurs with an incidence of at least 2000 cases per year
Early mortality is as high as 1 per hour if untreated
The peak incidence ndash fifth and sixth decades of life
Male to female--- 31
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 2: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/2.jpg)
Review ofAorticAnatomy
Layers of Aortahellip
What is dissection of aorta
Tear in the aortic intima that directly exposes an underlying diseased medial layer to the driving force (or pulse pressure) of intraluminal blood
This blood penetrates the diseased medial layer and cleaves the media longitudinally thereby dissecting the aortic wall
Driven by persistent intraluminal pressure the dissection process extends a variable length along the aortic wall typically antegrade but sometimes retrograde from the site of the intimal tear
The blood-filled space between thedissected layers of the aortic wallbecomes the false lumen
Shear forces may lead to further tears inthe intimal flap (the inner portion of thedissected aortic wall) and produce exitsites or additional entry sites for bloodflow into the false lumen
Distention of the false lumen with bloodmay cause the intimal flap to bow intothe true lumen and thereby narrow itscaliber and distort its shape
EPIDEMIOLOGY
Uncommon but potentially catastrophic illness
Occurs with an incidence of at least 2000 cases per year
Early mortality is as high as 1 per hour if untreated
The peak incidence ndash fifth and sixth decades of life
Male to female--- 31
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 3: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/3.jpg)
Layers of Aortahellip
What is dissection of aorta
Tear in the aortic intima that directly exposes an underlying diseased medial layer to the driving force (or pulse pressure) of intraluminal blood
This blood penetrates the diseased medial layer and cleaves the media longitudinally thereby dissecting the aortic wall
Driven by persistent intraluminal pressure the dissection process extends a variable length along the aortic wall typically antegrade but sometimes retrograde from the site of the intimal tear
The blood-filled space between thedissected layers of the aortic wallbecomes the false lumen
Shear forces may lead to further tears inthe intimal flap (the inner portion of thedissected aortic wall) and produce exitsites or additional entry sites for bloodflow into the false lumen
Distention of the false lumen with bloodmay cause the intimal flap to bow intothe true lumen and thereby narrow itscaliber and distort its shape
EPIDEMIOLOGY
Uncommon but potentially catastrophic illness
Occurs with an incidence of at least 2000 cases per year
Early mortality is as high as 1 per hour if untreated
The peak incidence ndash fifth and sixth decades of life
Male to female--- 31
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 4: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/4.jpg)
What is dissection of aorta
Tear in the aortic intima that directly exposes an underlying diseased medial layer to the driving force (or pulse pressure) of intraluminal blood
This blood penetrates the diseased medial layer and cleaves the media longitudinally thereby dissecting the aortic wall
Driven by persistent intraluminal pressure the dissection process extends a variable length along the aortic wall typically antegrade but sometimes retrograde from the site of the intimal tear
The blood-filled space between thedissected layers of the aortic wallbecomes the false lumen
Shear forces may lead to further tears inthe intimal flap (the inner portion of thedissected aortic wall) and produce exitsites or additional entry sites for bloodflow into the false lumen
Distention of the false lumen with bloodmay cause the intimal flap to bow intothe true lumen and thereby narrow itscaliber and distort its shape
EPIDEMIOLOGY
Uncommon but potentially catastrophic illness
Occurs with an incidence of at least 2000 cases per year
Early mortality is as high as 1 per hour if untreated
The peak incidence ndash fifth and sixth decades of life
Male to female--- 31
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 5: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/5.jpg)
The blood-filled space between thedissected layers of the aortic wallbecomes the false lumen
Shear forces may lead to further tears inthe intimal flap (the inner portion of thedissected aortic wall) and produce exitsites or additional entry sites for bloodflow into the false lumen
Distention of the false lumen with bloodmay cause the intimal flap to bow intothe true lumen and thereby narrow itscaliber and distort its shape
EPIDEMIOLOGY
Uncommon but potentially catastrophic illness
Occurs with an incidence of at least 2000 cases per year
Early mortality is as high as 1 per hour if untreated
The peak incidence ndash fifth and sixth decades of life
Male to female--- 31
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 6: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/6.jpg)
EPIDEMIOLOGY
Uncommon but potentially catastrophic illness
Occurs with an incidence of at least 2000 cases per year
Early mortality is as high as 1 per hour if untreated
The peak incidence ndash fifth and sixth decades of life
Male to female--- 31
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 7: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/7.jpg)
Clinical Presentation
Sudden onset of sharp tearing intractable chest pain may radiate to the back esp interscapular region
Asymmetrical peripheral pulse
Diastolic murmur or bruit
Pulmonary edema
Previously hypertensive now in shock
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 8: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/8.jpg)
LOCATION
Ascending aorta 65
Descending aorta 20
just distal to the origin of the left subclavianartery at the site of the ligamentumarteriosum
Aortic arch 10 and
Abdominal aorta 5
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 9: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/9.jpg)
Commonly used classifications
Stanford types A and B and
DeBakey types I II and III
Anatomical categories proximal and distalrdquo
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 10: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/10.jpg)
Stanford Type A All dissections involving the ascending aorta regardless of the site of origin
Type B All dissections
not involving the ascending aorta
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 11: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/11.jpg)
DeBakeyrsquos
DeBakeyrsquos Type I Originates in the
ascending aorta propagates at least to the aortic arch and often beyond it distally
Type II Originates in and is confined to the ascending aorta
Type III Originates in the descending aorta and extends distally down the aorta or rarely retrograde into the aortic arch and ascending aorta
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 12: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/12.jpg)
Proximal IncludesDeBakeytypes I and II or Stanford type A
Distal Includes DeBakeytype III or Stanford type B
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 13: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/13.jpg)
ETIOLOGY Hypertension 72 ndash 80 ( most common) cystic Medial degeneration as evidenced by
deterioration of medial collagen and elastin is most common predisposing factor
Atherosclerosis Connective tissue disorder (Marfan Ehlers-Danlos) Takayasu (giant cell) arteritis Pregnancy (normal women during 3rdtrimester) Congenital bicuspicaortic valve Aortic coarctation Skeletal abnormalities (scoliosis pectus) Mycotic aneurysm Aortic laceration
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 14: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/14.jpg)
Rare causes
Trauma
Iatrogenic
1 Intraarterial catheterization and
2 the insertion of intraaortic balloon pumps
3 Cardiac surgery Aortic valve replacement
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 15: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/15.jpg)
Predisposing conditions
Bicuspid aortic valve 7 -14
Coarctation of the aorta
Noonan and Turner syndromes
Cocaine abuse
Pregnancy third trimester amp postpartum period
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 16: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/16.jpg)
ACR Appropriateness Criteria for Aortic Dissection
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 17: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/17.jpg)
Laboratory data
1 Decreases in the hemoglobin and hematocrit are ominous findings suggesting the dissection either is leaking or has ruptured
2 BUN and creatinine are elevated if the dissection involves the renal arteries
3 Hematuria oliguria and even anuria(lt50 mLd) may occur if the dissection involves the renal arteries
4 CKMB and TroponinT may be elevated in acute thoracic aorta dissection
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 18: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/18.jpg)
In acute thoracic dissection ECG can mimic the changes seen in acute cardiac ischemia In the presence of chest pain these signs can make distinguishing dissection from AMI very difficult
STT depression and T wave inversion
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 19: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/19.jpg)
IMAGING FINDINGS
o Chest X ndash Ray
Mediastinal widening Left paraspinal stripe ldquo Calcium sign ldquois a
finding that suggests aortic dissection It is the separation of the intimal calcification from the outer aortic soft tissue border by 10 mm
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 20: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/20.jpg)
Double aortic knob sign (present in 40 of patients)
Diffuse enlargement of the aorta with poor definition or irregularity of the aortic contour
Inward displacement of aortic wall calcification by more than 10 mm
Tracheal displacement to the right
Pleural effusion (more common on the left side suggests leakage)
Pericardial effusion
Cardiac enlargement
Displacement of a nasogastric tube
Other radiographic findings include the following
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 21: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/21.jpg)
CT and CTA
CT especially with arterial contrast enhancement (CTA) is the investigation of choice able not only to diagnose and classify the dissection but also evaluate for distal complications
Post contrast CT (CTA preferably) gives excellent detail Findings include
intimal flap
double lumen
dilatation of aorta
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 22: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/22.jpg)
Identification of true lumen is important Helpful featurees
True lumen
Surrounded by calcifications (if present)
Smaller than false lumen
Usually origin of celiac trunk SMA and right renal artery
False Lumen
Flow or occluded by thrombus (chronic)
Delayed enhancement
Wedges around true lumen (beak-sign)
Collageneous media-remnants (cobwebs)
Larger than true lumen
Circular configuration (persistent systolic pressure)
Outer curve of the arch
Usually origin of left renal artery
Surrounds true lumen in Type A dissection
Chronic dissection flaps are often thicker and straighter than those seen in acute dissections
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 23: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/23.jpg)
Intimomedialflap inascendingaorta
Contrastextravasation intoanteriormediastinum
intimomedialflap in aorticarchMediastinal
hematoma
False lumen hypodensecompared to true lumen
True lumen hyperdensecompared to false lumen
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 24: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/24.jpg)
Type A dissection with clear intimaflap seen within the aortic arch RIGHT Type B dissection Entry point distal to left subclavianartery
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 25: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/25.jpg)
Type B dissection Green arrow indicates entry False lumen is indicated by yellow arrows and is seen spiraling around the true lumen
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 26: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/26.jpg)
Cobweb seen within the false lumen
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 27: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/27.jpg)
Dissection into abdominal arteries
The celiac trunc SMA and right renal artery flow usually originates from the true lumenLeft renal artery flow mostly originates from the false lumenImpaired perfusion of end-organs can be due to 2 mechanisms1) static = continuing dissection in the feeding artery (usually treated by stenting)2) dynamic = dissection flap hanging in front of ostium like a curtain (usually treated with fenestration
Left Continued dissection into the celictrunk showing bigger false lumen significantly contributing to organ perfusionRight SMA and renal artery involvement illustrating possible cause of organ malperfusion
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 28: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/28.jpg)
Rupture into pericardium and thoracic cavity
Even the slightest amount of fluid in pericardium mediastinum or pleural cavity is suggestive of rupture of the dissectionThe cases on the left show evident rupture with presence of extensive hematomaNote extreme hematothorax and hematomediastinum causing shift of the mediastinum and compression on the pulmonary veins and even aortaNo pericardial effusion visible
Left pericardial fluid hematoma indicatesrupture of the dissected aortaRightMassive hematoma caused by rupture ofthe dissected aorta into the mediastinumand pleural cavity no pericaldial hematoma
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 29: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/29.jpg)
Aneurysm with thrombus versus thrombosed dissection
It can be difficult to differentiate an aneurysm with thrombus from a dissection with a thrombosed false lumenIf there are intima calcifications this will be very helpfullA false lumen displaces the intimalcalcifications
LEFT Dissection with a thrombosed false lumenRIGHT Aneurysm with thrombus on the inner side of the intimal calcifications
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 30: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/30.jpg)
INTRAMURAL HEMATOMA
Intramural Hematoma is a result of ruptured vasa vasorum
Brief facts
bullSpontaneous hemorrhage caused by rupture of vasa vasorum in media13 of dissections usually no pulse deficitbullDifficult to distinguish from thrombosed ADbullCan proceed to classic dissection (16-47)bullLong time to diagnosis usually overlooked due to lack of non-enhanced scanbullMortality at 1 year after adismission~ 25
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 31: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/31.jpg)
Classic example of IMH Hyperdensehematoma on NECT Intima calcifications surround the true lumen
Same case CECT of Intramural hematoma
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 32: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/32.jpg)
Contrast‐filldaortaNo contrast in
intramural hematoma
CT
Non-contrast CT shows a cuff of high attenuation around the aortic lumen in the acute phase that is low attenuation on post-contrast CT Intimal calcification may be displaced inwardsUnlike aortic dissection no intimal flap is present
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 33: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/33.jpg)
Penetrating Atherosclerotic Ulcer
PAU is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wallIt has reached the media and produced a hematoma within the media
Brief facts
Patients with severe systemic atherosclerosisRarely rupture yet worse prognosis due to extensive atherosclerosis which causes organ failure (eg acute myocardial infarction)Cause of most saccular aneurysmsLocated in arch and descending aortaOften multiple (therefore surgical treatment difficult mostly treated medically)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 34: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/34.jpg)
Imaging features
Extensive atherosclerosis with severe intimal calcifications and atherosclerotic plaquesFocally displaced and separated intima calcificationsCrater andor contrast extravasation-Focal IMH longitudinal spread limited by mediafibrosisPossibly enhancing aortic wall
Typical illustration of PAU focal outpouchings of contrast separating extensive intimal calcifications
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 35: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/35.jpg)
Complications
Complications of all types of aortic dissection include
dissection and occlusion of branch vesselsabdominal organ ischaemialimb ischaemiaischaemic strokeparaplegia involvement of artery of Adamkiewicz
distal thromboembolismaneurysmal dilatation this is an indication for endovascular or surgical interventionaortic ruptureA type A dissection may also result incoronary artery occlusionaortic incompetencerupture into pericardial sac with resulting cardiac tamponade
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 36: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/36.jpg)
MRI
1 Intimal flap2 Slow flow and clot in false lumen
Lumen Partition of a three-dimensional contrast-enhanced MRA shows intimal flap (arrows ) in the distal aortic arch and descending aorta
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 37: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/37.jpg)
1 Freely movable flap within the lumen of the vessel2 Differential Doppler detection of true vs false lumen
Freely movable flap within the aorta
Transesophgeal echocardiogram
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 38: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/38.jpg)
Angiography
1 Intimalflap2 True and false lumen (may be failure if the falsechannel is thrombosed)3 Aortic regurgitation4 Coronary artery
Oblique arteriogram of the thoracic aorta demonstrates the double-barrel aorta sign of aortic dissection Both the true and false lumina are opacified
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 39: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/39.jpg)
MANAGMENT
Type A aortic dissection
Treatment for type A aortic dissection may includeSurgery Surgeons remove as much of the dissected aorta as possible block the entry of blood into the aortic wall and reconstruct the aorta with a synthetic tube called a graft If the aortic valve leaks as a result of the damaged aorta it may be replaced at the same time The new valve is placed within the graft used to reconstruct the aorta
Medications Some medications such as beta blockers and nitroprusside (Nitropress) reduce heart rate and lower blood pressure which can prevent the aortic dissection from worsening They may be given to people with type A aortic dissection to stabilize blood pressure before surgery
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 40: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/40.jpg)
Type B aortic dissection
Treatment of type B aortic dissection may include
Surgery The procedure is similar to that used to correct a type A aortic dissection Sometimes stents mdash small wire mesh tubes that act as a sort of scaffolding mdash may be placed in the aorta to repair complicated type B aortic dissections
Medications The same medications that are used to treat type A aortic dissection may be used without surgery to treat type B aortic dissectionsAfter treatment you may need to take blood pressure lowering medication for life In addition you may need follow-up CTs or MRIs periodically to monitor your condition
![Page 41: Aortic dissection 01](https://reader034.vdocuments.net/reader034/viewer/2022042614/559f3c121a28ab81748b4589/html5/thumbnails/41.jpg)