copy of lvot o ii

• Left ventricular out flow tract obstruction (DD)

By Dr_ Mona SallamBy Dr_ Mona Sallam

Anatomy of LVOT Anatomy of LVOT

The left ventricular outflow tract is considered to be that region of the left ventricle Lies between the anterior cusp of the mitral valve and the ventricular septum

this outflow tract has been called the aortic vestibule, And the sub aortic, subvalvar, or subvalvular region By different workers.

Outflow tract is a complex musculomembranous Channel or tunnel which has a length of about 25 mm In the adult heart: its length does, however, show Considerable variation in different hearts.

it must be emphasized that there Is no line of demarcation on its anterior Wall to indicate the lower border of the tract. This Is indicated on its posterior wall by the free lower Border of the anterior cusp of the mitral valve( a Uniquely important structure in cardiac anatomy).

Left ventricular outflow tract obstructions (LVOTOs) encompass a series of stenotic lesions starting in the anatomic left ventricular outflow tract (LVOT) and stretching to the descending portion of the aortic arch .

Obstruction may be subvalvular, valvular , or supravalvar.

All of these lesions impose increased after load on the left ventricle and, if severe and untreated, result in hypertrophy and eventual dilatation and failure of the left ventricle.

LVOTOs are congenital in the vast majority of individuals younger than 50 years; some variants of sub aortic obstruction are the exception.

. It is imperative to consider all patients with LVOTO at a high risk for developing infective endocarditic, and one should always institute appropriate measures for prophylaxis.

Figure 1. Artist’s

from a super lateral orientation. A, Gradient echo cardiac MR image as viewed from the frontal projection demonistrating flow acceleration at site

of supravalvular aortic Stenosis (white arrow)

rendering of the LVOTO lesions in sequence as viewed

• . B, Classic radiological signs of coarctation of the aorta: rib notching (white arrows) as seen on a poster anterior chest x-ray in a patient with coarctation of the aorta. The rib notching is caused by erosion of the inferior rib margins by dilated pulsatile posterior intercostals collateral arteries. The black arrow points to the Figure 3 silhouette that is created by the combination of a dilated left subclavian artery above and a convex dilated descending aorta below the site of coarctation.

viewed from the postero anterior projection, demonstrating a plethora of dilated intercostals collateral arteries in a patient with coarctation of the aorta. . D, Continuous-wave Doppler signal through the site of coarctation with a systolic flow velocity of 3.4 m/s (Syst) and a peak pressure gradient of 46 mm Hg. Horizontal arrows point to the peak of the systolic velocity profile. The vertical arrows point to the "diastolic tail,“ a diastolic pressure gradient at the site of coarctation leading to nearly continuous flow, indicating significant coarctation of the aorta. E, Autopsy specimen of a calcified and steno tic bicuspid aortic valve. The white arrow points to the false raphe. There is fusion of the left and right coronary cusps.

C, Three-dimensional reconstruction of a cardiac CT angiogram as

• Obstruction to LVOT is localized most commonly to aortic valve . However obstruction may also occur above the valve (supravalvular stenosis ) or below the valve (subvalvular stenosis ) or may be caused by hypertrophic cardiomyopathy (HCM ).

Valvular (obstruction )aortic Valvular (obstruction )aortic stenosis stenosis

• Most commonly, aortic stenosis is due to age-related progressive calcification of the normal trileaflet valve, being responsible for more than 50% of cases.Other causes include calcification of a congenital bicuspid aortic valve (30-40% of cases) and rheumatic aortic stenosis (less than 10% of cases). Typically, aortic stenosis due to calcification of a bicuspid valve manifests when individuals reach their 40s and 50s, whereas that due to calcification of a normal valve tends to manifest later, in the 70s and 80s. Hypertension, diabetes mellitus, hyperlipoproteinemia and uremia may speed up the process.

Age related calcific aorticAge related calcific aortic stenosisstenosis

It should be differentiated from age related sclerosis which is defined as irregular thickening of aortic valve leaflets detected by echocardiography without significant obstruction .

Calcium deposits at fusion

lines of valve leaflet

• Calcific stenosis share the traditional risk factors of atherosclerosis (smoking , hypertension,hyperlipeidemia ,..etc )and also carries 50%risk of myocardial deaths and myocardial infarction.

Although normal tear and wear of valveleaflet is thought to manifest as seniledegeneration , the evolving concept isthat Atherosclerosis may contribute topathophysiology of calcific stenosis.

Bicuspid Aortic ValveBicuspid Aortic Valve

• BAV is one of the most common congenital cardiovascular malformations,

with an estimated incidence of 1% to 2%.

• BAV is sometimes inherited, and familyclusters have been studied. Inheritance patternsare autosomal dominant with variable penetrance.

• Turbulent flow and increased leaflet stress caused by abnormal architecture ( small orifice area ,extended areas of valve contact, and restricted motion,….etc ). These stresses lead to valve damage, scarring, calcification, and resultant stenosis and regurgitation

• Two-dimensional echocardiography is recommended as a screening tool for the offspring and first-degree relatives (especially males) of patients identified as having a bicuspid aortic valve because a high recurrence rate (as much as 12-17%) has been shown in several families.

Two-dimensional echocardiogram of typical bicuspid aortic valve in diastole and systole. Valve margins are thin and pliable and open widely, creating the fish mouth appearance

Parasternal long-axis echocardiogram showing doming of a bicuspid aortic valve.

BAV disease is gradually progressive BAV disease is gradually progressive in the majority of cases being typically in the majority of cases being typically presented with sever aortic stenosis presented with sever aortic stenosis

after 50years of age after 50years of age

BAV are often associated with dilated ascending aorta with increased risk of aortic rupture or dissection attributed to accelerated degeneration of aortic media .

• The risk of dissection in patients with BAV is estimated to be 5 to 9 times that of the general population and is highest in cases with concomitant coarctation.

• Surgery to repair or replace the aortic root should be considered when the root diameter is >5 cm or if the rate of increase in diameter is >0.5 cm/y.

• Yearly imaging of the aortic root and ascending

aorta is indicated in patients with a dilated aortic root (4 cm).

• We perform yearly Tran thoracic echocardiography and have increasingly utilized CT and MR angiography over the past decade to quantify extent of dilatation and as the primary imaging modality when the aortic root or ascending aorta cannot be assessed accurately by echocardiography.

Figure 2 :AGradient echo cardiac MR image axial cut at the level of a calcified stenotic bicuspid aortic valve (white arrow) during systole. The calcium appears black and is predominantly deposited at the leaflet tips There is fusion of the right and left coronary cusps. The right atrium (RA) and left atrium (LA) are labeled.

B: Frontal projection of the same patient. Note the systolic doming despite calcification of this aortic valve (white arrow) and the severely dilated ascending aorta (Ao) with characteristic effacement of the sinotubular junction.

Note that the dilated ascending aorta tends to normalize proximal to the

innominate artery.

Rheumatic aortic stenosisRheumatic aortic stenosis

• . rheumatic stenosis results from adhesions and fusions of commissuers and cusps and vascularization of the leaflets of valve ring lead to retraction and stiffness of both leaflets .

Calcific nodules develop on both valve surfaces, and the orifice is reduced to small rounded or triangular opening

Aorta has been removed to show thickened, fused aortic valve leaflets and opened coronary arteries from above

Clinical assessment of patient Clinical assessment of patient with valvular obstructionwith valvular obstruction

History : (LATENT PHASE ); patient with valvular

aortic stenosis being at first a symptomatic and accidentally discovered on routine physical examination with risk of sudden death less than1% per year .

symptom typically develop at age of 50- 70years with BAV and at older than 70with

calcific stenosis of trileaflet valve

• This patient is in need for close clinical as well as echo-Doppler follow up

• patient should report onset of symptom to his physician (the most common clinical presentation in patient under prospective follow up is a gradual decrease in exercise tolerance , fatigue or dyspnea on exertion).

• Doppler aortic jet velocity is the strongest predictor of progression to symptom .

SYMPTOMATIC PATIENT ; the classic symptom of aortic stenosis are Angina : either caused by myocardial supply–

demand mismatch or underlying CAD (represent 50%of patient with angina) .very rarely caused by Ca emboli to coronary bed .

Syncope :it most commonly occur during exertion due to cerebral hypo perfusion as a

result of systemic vasodilatation in presence of fixed CO (may be presented also by graying out spells or dizziness on effort ) .

It has been also attributed to a abnormal baroreceptor response in sever aortic stenosis or a vasodepressor response with increased LVEDP. Syncope at rest can result from transient attack of atrial or ventricular fibrillation or being caused by transient atrioventricular block due to extension of calcification to the conducting system .

Heart failure :exertional dyspnea progress to orthopnea or PND and fatigue caused by LV systolic or diastolic dysfunction .

• Age in years

• Survival %

• 0 63605040

100

80

60

40

20

2 3 5

• Angina

• syncopefailure

• Patient survival in aortic stenosis

Associated symptoms

In Heyde's syndrome, aortic stenosis is associated with angiodysplasia of the colon. Recent research has shown that the stenosis causes a form of von Willebrand disease by breaking down its associated coagulation factor (factor VIII-associated antigen, also called von Willebrand factor), due to increased turbulence around the stenosed valve.

Physical examination

General examination Carotid pulse ; slow rising ,late peaking ,low

amplitude pulse ( pulsus parvus et tardus ) when present its specific for aortic stenosis. However elder and patient with concomitant AR maintain normal pulse in spite of sever stenosis

Note : this finding is rare with LVOTO above or below the valve

• Blood pressure ;when sever AS is present systolic blood pressure and pulse pressure may be reduced .However in elder and concomitant AR both systolic pressure and pulse pressure may be normal or even increased

• Radiation of AS murmur may be felt as palpable thrill or carotid shudder.

LOCAL EXAMINATION :

• Palpation ; The apical impulse is non displaced ,

diffuse ,and sustained . However becomes displaced inferiorly and laterally with LV failure

Double apical impulse represent a palpable a wave caused by non compliant LV .

A systolic thrill best appreciated over 2nd right inter costal space while patient is sitting and leaning forward ,during deep expiration

AUSCULTATION : An easily heard systolic, crescendo-decrescendo

(i.e., 'ejection') murmur is heard loudest at the upper right sternal border, at the 2nd right intercostal space, and radiates to the carotid arteries bilaterally.

murmer may be preceded by aortic opening sound in young adult patient with BAV .

The murmur increases with squatting, decreases with standing and isometric muscular contraction, which helps distinguish it from hypertrophic obstructive cardiomyopathy (HOCM).

The murmur is louder during expiration, but is also easily heard during inspiration. The more severe the degree of the stenosis, the later the peak occurs in the crescendo-decrescendo of the murmur.

note :in patient with calcific stenosis high frequency component radiate to apex (the so called Gallavardin sign ).

• The second heart sound (A2) tends to become decreased and softer as the aortic stenosis becomes more severe. (as calcification and immobility of the aortic valve make A2 inaudible ,P2 is masked by the harsh murmer

• Paradoxical splitting of S2 denote associated LBBB or LV failure

• S1 is normal or soft

• S4 is common because of reduced LV compliance

• Maneuvers performed during physical examination can help to differentiate different types of LVOTO ,whether this is at , below or above the valve .That is demonstrated in the following table

Maneuver /finding

Valvular Supra-valvular

Sub-valvular

HCM

Pulse volume after PVC

INCREASES INCREASES INCREASES DECRESES

Effect of valsalva on systolic murmer

DECREASE DECREASE DECREASE INCREASE

AR COMMON COMMON COMMON COMMON

S4 COMMON UNCOMMON UNCOMMON COMMON

CAROTID PULSE

PARVUS ET TARDYS

UNEQUAL NORMAL OR PARVUSET TARDUS

RAPID JERKY UPSTROK(BISFIRIANCE )

Diagnostic tests

ELECTROCARDIGRAM( ECG )

The principle ECG changes are LVH (80% ) AND left atrial enlargement .

CHEST RADIOGRAPHY the heart is of normal size unless LV dysfunction or AR

coexist result in cardiomegally dilatation of ascending aorta is common association with BAV calcification of aortic root can be demonstrated on

fluoroscopy there may be radiological signs of LA enlargement or

pulmonary venous hypertension .

Echocardiogram ;

Transthoracic echo : It is the standard tool for evaluation and

following patient with aortic stenosis and selecting them for surgical intervention

Anatomic evaluation of the aortic valve is based on a combination of short- and long-axis images to identify the number of leaflets, and to describe leaflet mobility, thickness, and calcification .

Diagnosis of BAV is most reliable when the two cusps are seen in systole with only two commissuers forming an elliptical systolic orifice. Long-axis views may show an a symmetric closure line, systolic doming, or diastolic prolapse of the cusps but these findings are less specific than a short-axis systolic image.

With calcification of a bicuspid or tricuspid valve, the severity of valve calcification can be graded semi-quantitatively, as mild (few areas of dense echogenicity with little acoustic shadowing), moderate, or severe (extensive thickening and increased echogenicity with a prominent acoustic shadow). The degree of valve calcification is a predictor of clinical outcome.

Rheumatic AS is characterized by commissural fusion, resulting in a triangular systolic orifice, with thickening and calcification most prominent along the edges of the cusps. Rheumatic disease nearly always affects the mitral valve first, so that rheumatic aortic valve disease is accompanied by rheumatic mitral valve changes

• Figure 2 Echocardiography appearance in aortic stenosis. Parasternal short-axis views in (A) calcific degenerative disease, (B) bicuspid aortic valve, and (C) rheumatic disease.

• Recommendations for data recording and

measurement for AS quantitation

•

Continuous wave Doppler of sever aortic stenosis jet show

measurement of maximum velocity and tracing of velocity

curve to measure mean pressure gradient

primary hemodynamic parameters recommended for clinical evaluation of AS severity are:

● AS jet velocity

● Mean transaortic gradient

● Valve area by continuity equation.Recommendations for classification of AS severity

ESC Guidelines.

AHA/ACC Guidelines.

• Never to evaluate AS with uncontrolled

hypertension as it may not accurately reflect disease severity. Thus, control of blood pressure is recommended before echocardiography evaluation, whenever possible.

• The echocardiography report should always include a blood pressure measurement recorded at the time of the examination to allow comparison between serial echocardiography studies and with other clinical data.

•

• Resolution of apparent discrepancies in

measures of AS severity

In addition to evaluation of AS etiology and hemodynamic severity, the echocardiography evaluation of adults with aortic valve disease should include evaluation of :

1) LV hypertrophy and systolic function2) Measurement of aortic root dimensions (look for

associated coartication in suprasternal window).3) Doppler assessment of concomitant AR .4) Measurement of pulmonary artery pressure and

assessment of RV function .5) Associated MVD .

Transesophageal echo (TEE ); Its useful in detecting morphology of the valve

in congenital stenosis .assessment of annulus dimension is critical for

the choice of prosthesis size. For this , TEE may be superior to TTE

Dobutamin echo and stresse echocardiography

Stress echo in a symptomatic patient may provide information about exercise induced symptoms or blood pressure response , however contraindicated in symptomatic patient

DSE is useful in assessment low-flow /low gradient aortic stenosis ( Effective orifice area 1.0 cm2, LV ejection fraction 40%and Mean pressure gradient 30–40 mmHg(.

Dobutamin stress provides information on the changes in aortic velocity, mean gradient, and valve area as flow rate increases, and also provides a measure of the contractile response to Dobutamin, measured by the change in SV or ejection fraction

• . These data may be helpful to

differentiate two clinical situations:

● Severe AS causing LV systolic dysfunction.

● Moderate AS with another cause of LV dysfunction (e.g. myocardial infarct or a primary cardiomyopathy).

• The recommend reliable findings are:

● An increase in valve area to a final valve area >1.0 cm2 suggests that stenosis is not severe.

● Severe stenosis is suggested by an AS jet> 4.0m /sec or a mean gradient> 40 mmHg provided that valve area does not exceed 1.0 cm2 at any flow rate.

● Absence of contractile reserve (failure to increase SV or ejection fraction by 20%) is a predictor of a high surgical mortality and poor long-term outcome although valve replacement may improve LV function and outcome even in this subgroup

CARDIAC CATHETERIZATION Uses of catheterization in AS is limited to preoperative catheterization “CA” in

patient >50years , patient with angina and those with risk factor for CAD (CLASS I ).

catheter –derived haemodynamic data to further evaluate severity of AS when clinical and echo data are discrepant (CLASS I ).

•

Simultaneous left ventricular and aortic pressure tracings demonstrate a pressure gradient between the left ventricle and aorta, suggestingaortic stenosis. The left ventricle generates higher pressures than what is transmitted to the aorta. The pressure gradient, caused by aortic stenosis, is represented by the green shaded area. (AO = ascending aorta; LV = left ventricle;

ECG = electrocardiogram.)

MANGMENT MANGMENT

• valvular obstruction need regular clinical and echo follow up (every 3-5y for mild stenosis and every 1-2y for moderate stenosis ) , once severity is demonstrated patients should be considered a surgical candidates and role of medical therapy is restricted for inoperable cases and management of associated LV failure and concurrent cardiac conditions as HTN and CAD .

Percutaneous aortic balloon valvuloplsty and percutaneous valve replacement

• For adolescent and young adults balloon aortic valvotomy should be considered as it result in remarkable haemodynamic improvement, however abnormal valve anatomy result in turbulent blood flow and so valve deformation ending in aortic regurgitation or restenosis that requires AVR later on .

Surgical aortic valve replacement

• AVR is the definitive therapy for symptomatic AS and is mandatory unless there are compelling contraindications for operation. AVR is usually accomplished using a bioprosthetic or mechanical valve, performed through a median sternotomy incision, although recently less invasive techniques have been carried out through smaller hemisternotomy incisions .

• For pediatric and adolescent patient with growth potential Ross procedure is best suited where pulmonary valve and main pulmonary artery are removed as unit and placed in aortic position with reimplantation of coronary arteries as autograf is capable of growth, dose not require anticoagulation and has an excellent hemodynamics .

• for patients older than 60 years bioprostheses including porcine heterografts and bovine pericardial prostheses as structural deterioration is much slower in this age group and these valves has low risk for thromboembolism and don’t necessitate long term anticoagulation.

Recommendations for Aortic Valve Replacement in Aortic Stenosis• 1. Symptomatic patients with severe AS I• 2. Patients with severe AS undergoing coronary artery bypass surgery I or surgery on the aorta or other heart valves• 3.patient with sever AS and left ventricular EF <50% I • 4. Patients with moderate AS undergoing coronary artery bypass

surgery or surgery on the aorta or other heart valves II a• 5. Asymptomatic patients with severe AS and Abnormal• response to exercise (e.g., hypotension) II b• 6. Asymptomatic patients with severe AS if there is a high likelihood of rapid

progression (age, calcification , CAD ,….).• 7.AVR can be considered in patient undergoing CABG who have mild AS

with high possibility of rapid progression (presence of moderate to sever valve calcification). II b

• 8. AVR may be considered for a symptomatic patient with sever aortic stenosis (AVA <0.6cm2 , mean gradient >60mmHg ,and jet velocity >5.0mper second )when expected operative mortality <1.0%. II b

• 6. Prevention of sudden death in a symptomatic patients with none of the findings listed underclass II a/II b III

Subvalvular obstruction Subvalvular obstruction the most relevant conditions associated to subaortic

obstruction involves 1. Hypertrophic Cardiomyopathy (HC)

2.Subaortic obstruction after mitral valve repair (SAM effect)

3 .“Mid-ventricular obstruction” and SAM after aortic surgery

4.Fixed discrete subaortic stenosis

5. LVOTO in atrioventricular septal defect (AVSD)

6. Multiple levels LVOT obstruction : the spectrum of the hypo plastic left heart syndrome and the Shone complex

• 7. Miscellaneous causes of LVOTO. Other abnormalities directly or indirectly related to the components of the outflow tract

such as tissue tags ,membranous septum aneurysm, anomalous attachment of the mitral valve (especially in the setting of true cleft anterior leaflet) or hypertrophy of the anterolateral muscle of the LV (Moulaert’s muscle) may be recognized as anatomic causes of LVOTO

Fixed discrete Fixed discrete subaortic stenosissubaortic stenosis

Fixed subvalvular aortic stenosis accounts for 10% to 20% of cases of aortic stenosis in children, and the male to female ratio is 2:1 to 3:1 .Associated cardiac defects are present in more than half of cases . Common associated defects include ventricular septal defect, coarctation of the aorta, atrioventricular septal defect, and valvular aortic stenosis.

The obstruction in fixed subvalvular aortic stenosis usually consists of a collar or ridge of membranous and/or fibro muscular tissue encircling the left ventricular outflow tract, or in some cases it may be diffuse and tunnel-like .

Mitral valve anomalies are also frequently present and likely play a role in the pathophysiology of the obstruction in some patients .(insertion of a papillary muscle or chordal tissue into the septum or aortic leaflet, accessory mitral valve tissue, and muscularization of the subaortic portion of the anterior leaflet).

The aortic valve may be thickened, and is

usually tricuspid. The aortic valve abnormality appears to be acquired and may be a consequence of the turbulent flow jet damaging the aortic valve cusps , but might also result from progression of the underlying disease substrate.

Most cases seem sporadic, although familial subaortic stenosis has been reported .

Clinical Features and Diagnostic Clinical Features and Diagnostic MethodsMethods

The diagnosis of subaortic stenosis frequently surfaces during echocardiograph evaluation at the time of diagnosis or follow-up of associated congenital heart disease, such as ventricular septal defect or coarctation of the aorta.

Patients with isolated subaortic stenosis usually present with an asymptomatic heart murmur. Commonly the patient is first thought to have an innocent murmur, but as the stenosis progresses the murmur becomes more typical of left ventricular outflow tract obstruction.

Chest pain and syncope may occur but generally nly when the stenosis is severe.

The systolic ejection murmur is loudest at the mid left sternal border and radiates to the upper sternal borders and into the suprasternal notch. A systolic click is rare, which helps to differentiate subvalvular aortic stenosis from valvular aortic stenosis.

The left ventricular impulse may be hyper -dynamic, and associated findings of aortic regurgitation and/or mitral valve regurgitation may be present.

• The ECG usually demonstrates left ventricular hypertrophy, even in many cases with mild stenosis although the ECG may occasionally be normal even in severe subaortic stenosis .

• The chest radiograph is generally normal, and dilation of the ascending aorta is much less common than in valvular aortic stenosis

Echocardiography with Doppler evaluation is highly sensitive and specific for making the diagnosis of subaortic stenosis and defining the anatomy of the lesion .

Early systolic partial closure and fluttering of the aortic leaflets may be present .

Careful evaluation of the aortic and mitral valve anatomy and function is mandatory, as is a thorough search for associated lesions.

Pulsed Doppler demonstrates velocity acceleration and aliasing in the outflow tract beneath the valve, and continuous wave Doppler allows accurate calculation of the peak instantaneous and mean pressure gradients

Coexistent valvular aortic stenosis is confirmed by an additional pulsed Doppler velocity increase above the aortic valve.

• Transesophageal echocardiography may be helpful in further defining left ventricular outflow tract anatomy and is commonly performed intraoperatively to assist during repair by evaluating the valve's anatomy and function pre- operatively and postoperatively.

Tran thoracic echocardiogram in the Parasternal long-axis orientation demonstrating a discrete subaortic membrane (white arrow) during diastole. The anterior mitral leaflet is labeled (AML). B, Color-flow Doppler in systole demonstrating flow acceleration at the subaortic membrane well below the level of the aortic valve .

• Invasive cardiac catheterization is usually unnecessary unless echocardiography is equivocal.

• Magnetic resonance (MR) imaging can also be used to clarify anatomy and quantify flow velocity.

MANGMENTMANGMENT

• Although balloon dilation has been reported, long-term success is limited, and treatment for subaortic stenosis is surgical

• Surgical intervention may be indicated at time of repair of primary lesions or in cases with discrete obstruction when the obstruction is severe enough to raise concerns

• Surgical intervension is indicated when a mean gradient across the LVOT is more than 30mmHg to avoid future aortic leaflet damage .

• Surgery involves fibromectomy , with care to avoid damage to aortic valve or to create a traumatic VSD .

Hypertrophic Hypertrophic Cardiomyopathy (Cardiomyopathy (HCM )HCM )

o Hypertrophic cardiomyopathy (HCM) is the most frequent genetic cardiac disease that causes sudden death in young people, with an incidence of 1:500 adults.

o Characterized by a thickened but non dilated left ventricle in the a absence of another cardiac or systemic condition capable of producing the magnitude of hypertrophy evident .

• GeneticsGenetics– Autosomal DominantAutosomal Dominant– Caused by missense mutation in gene that Caused by missense mutation in gene that

encode for protein in cardiac sarcomere.encode for protein in cardiac sarcomere.• Most common: gene encoding beta-myosin heavy Most common: gene encoding beta-myosin heavy

chain and myosin-binding protein C.chain and myosin-binding protein C.

– Phenotypic expression: occurs 1 in every 500 Phenotypic expression: occurs 1 in every 500 adults, including abnormal LV hypertrophyadults, including abnormal LV hypertrophy

Morphologic PatternsMorphologic Patterns– Asymmetric septal hypertrophy (most common)Asymmetric septal hypertrophy (most common)– Concentric hypertrophyConcentric hypertrophy– Apical hypertrophy (often associated with a “spade” Apical hypertrophy (often associated with a “spade”

deformity of the left ventricle and marked T wave deformity of the left ventricle and marked T wave negativity on the electrocardiogramnegativity on the electrocardiogram )

– Free wall LV hypertrophyFree wall LV hypertrophy– Basal septal hypertrophyBasal septal hypertrophy

• Causes narrowing LVOT and provides substrate for Causes narrowing LVOT and provides substrate for dynamic obstructiondynamic obstruction

• Blood flow velocity across narrowed LVOT produces Blood flow velocity across narrowed LVOT produces Venturi effect, consequently mitral leaflets and support Venturi effect, consequently mitral leaflets and support apparatus are drawn toward septum (SAM), contributing apparatus are drawn toward septum (SAM), contributing to LVOT obstruction and causing mild to moderate to LVOT obstruction and causing mild to moderate posteriorly directed MR.posteriorly directed MR.

• Morphologic variants of hypertrophic

• cardiomyopathy

A: Normal or mildly hypertrophied LV (the electrocardiogram is often abnormal); B: Idiopathic subaortic stenosis (IHSS) or LV outflow tract (LVOT) obstructive HCM;

C: Asymmetrical septal hypertrophy (ASH); D: Elderly HCM; F: Reversed ASH; G: LV wall thinning, low LVEF, and left and right atrial enlargement;

H: Mixed LVOT and midcavity obstructive HCM; I: Apical HCM; J: Cavity obliteration; K: Biventricular hypertrophy and obstruction; L: Symmetric hypertrophy

Pathophysiologic mechanisms in hypertrophic cardiomyopathy. C.O., cardiac output; LAp, left atrial pressure;MR, mitral regurgitation; SAM, systolic anterior motion of the mitral

valve.

Clinical presentation Clinical presentation History

• HCM may be newly diagnosed at any age from early childhood to advanced age.

• The clinical presentation of HCM varies widely. Patients may be completely asymptomatic, with

the diagnosis made on the basis of a heart murmur, abnormal ECG , or during screening prior to participation in competitive athletics .

• Even patients with massive hypertrophy of the heart can be completely asymptomatic and some patients are not diagnosed until they present with sudden cardiac death.

5-19-20095-19-2009 i love iti love it

ECG from a patient with apical HCM showing the “giant T negativity syndrome” (T waves more negative than 10 mm) in the precordial leads,

usually maximal in V4.

©

The typical triad of symptomsThe typical triad of symptoms in HCM includes in HCM includes

• dyspnea on exertion,

• angina

• presyncope or syncope

• Dyspnea is the most common presenting symptom and occurs in as many as 90% of symptomatic patients. The dyspnea in HCM is due to increased left atrial pressure, which can result from abnormal left ventricular diastolic function, outflow tract obstruction, or significant mitral regurgitation.

• Angina pectoris is common even in the absence

of epicardial coronary artery disease and is related to an abnormal myocardial oxygen supply/demand mismatch due to the hypertrophied left ventricular walls, increased arteriolar compressive wall tension caused by diastolic relaxation abnormalities, and endothelial dysfunction.

• Syncope may be due to arrhythmias or a sudden increase in outflow tract obstruction. Patients with HCM frequently have abnormal autonomic function ,and vasodepressor syncope may be part of the mechanism of syncope.

• Syncope identifies children with hypertrophic cardiomyopathy at significantly increased risk of sudden death and warrants an urgent evaluation and aggressive treatment.

• Like syncope, presyncopal episodes warrant a directed evaluation to rule-out malignant arrhythmias .

Sudden cardiac death – This is the most devastating presenting

manifestation and, unfortunately, may be the first clinical manifestation of the disease, even among asymptomatic patients.

– Sudden cardiac death has the highest incidence in preadolescent and adolescent children and is typically associated with sports or vigorous exertion.

– The arrhythmia that causes sudden death is

ventricular fibrillation in more than 80% of individuals with hypertrophic cardiomyopathy.

Many patients with hypertrophic cardiomyopathy develop ventricular fibrillation following atrial fibrillation, atrial flutter, supraventricular tachycardia associated with Wolff-Parkinson-White syndrome, ventricular tachycardia, and/or low–cardiac-output hemodynamic collapse.

Early diagnosis is of prime importance if death is to be prevented by prescription of an appropriate level of safe activity, medications, surgery, and/or an implantable cardioverter defibrillator.

Physical ExaminationPhysical Examination in HCMin HCM

• Physical examination findings are always abnormal when there is obstruction of the outflow tract, but in non-obstructive HCM the physical examination may be less obvious.

o Inspection Inspection • The jugular venous pressure may be

slightly increased, with a prominent “a” wave indicating abnormal diastolic function of the right side of the heart.

o palpationpalpation

• The hallmark of the physical examination in HCM is the finding of severe myocardial hypertrophy; This is detected by palpation of the left ventricular apex, which is localized but markedly sustained.

• There frequently is a palpable presystolic impulse of the augmented atrial contraction present (palpable S4).

The carotid pulse has a rapid upstroke due to the

hyperdynamic systolic function and rapid ventricular emptying.

In the presence of ventricular outflow tract obstruction, the carotid upstroke has a distinctive “jerky” bifid quality (spike-and-dome pulse). The spikeis the initial rapid ventricular emptying phase, where as the dome corresponds to the onset of ventricular obstruction, followed by the more gradual increase inventricular pressure to overcome the gradient.

C, bifid pulse characteristic of IHSS;

Auscultation Auscultation Heart sounds

• The first heart sound is normal in patients with hypertrophic cardiomyopathy.

• The second heart sound can be normal or usually split; however, in some patients with hypertrophic cardiomyopathy and extreme outflow gradients, the second heart sound split paradoxically.

• A third heart sound or gallop is common in children with hypertrophic cardiomyopathy but does not have the same ominous significance as in patients with valvular aortic stenosis or in adults.

• A fourth heart sound is frequently heard and is due to

atrial systole against a highly noncompliant LV.

A harsh systolic ejection murmur is heard across the entire precordium and radiates to the apex and base of the heart but not the neck. In many instances, a separate mitral regurgitation murmur may be auscultated (holosystolic ,blowing ,and radiate to axilla ).

Both murmurs respond in a similar manner to examination maneuvers that change the loading conditions of the left ventricle;

• The murmur of HCM is increased by maneuvers that decrease left ventricular end-diastolic volume (decreased venous return, decreased afterload, increased contractility, pure vasodilators, inotropes, dehydration, and the Valsalva maneuver).

• The murmur decreases with squatting, passive leg raising, negative inotropes such as β-blockers, verapamil, disopyramide, and any maneuver that increases left ventricular end-diastolic volume.

• EVALUATION

— Several modalities are used to evaluate patients who are thought to have HCM (because of a positive family history) or who present with the symptoms or physical findings suggestive of HCM

The best first step is an The best first step is an echocardiogram echocardiogram

• Echocardiographic assessment in a patient with HCM requires comprehensive imaging of the left ventricle from several projections, including Parasternal long axis, serial short axis views, and imaging from the apical and sub costal windows.

(Demonstrates cardiac morphology and function, (Demonstrates cardiac morphology and function, extent of SAM of the MV, degree of MR, and extent of SAM of the MV, degree of MR, and

severity of LVOTseverity of LVOT gradient)gradient)

• The Parasternal long axis view is of pivotal importance for orientation, The long axis projection examines the profile of the ventricular septum and left ventricular outflow tract, with good visualization of the aortic valve and mitral valve, including the subvalvar apparatus. From this view, the relations between the basal septum, mitral valve, and aortic valve during the cardiac cycle can be appreciated

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Typical M mode echocardiogram from a patient with hypertrophic cardiomyopathy highlighting the four main echocardiographic features of the

condition.

Prasad K et al. Heart 1999;82:III8-III15

©1999 by BMJ Publishing Group Ltd and British Cardiovascular Society

Typical M mode echocardiogram from a patient with hypertrophic cardiomyopathy highlighting the four main Echocardiographic features of the condition:(A) Midsystolic closure of the aortic valve (arrowhead)

(B) systolic anterior motion of the mitral valve (arrow) and asymmetric left ventricular hypertrophy together with a small, vigorously contracting left ventricle.

(C) and (D), the M mode beam passes through the septum and posterior wall beyond the mitral valve, at the level of the papillary muscles and apex, demonstrating the large reduction of left ventricular end systolic dimensions.

• Multiple short axis sections from the mitral valve level down to the most distal segment, together with good, not foreshortened, apical two and four chamber views, are fundamental to a complete evaluation. Wall thickness should be measured in four segments anterior and posterior septal, lateral and inferior to characterise the extent and distribution of ventricular hypertrophy .

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An example of serial short axis, cross sectional views of the left ventricle at three levels—the mitral valve, papillary

muscles, and apex—demonstrating the segments of myocardial wall measured routinely in patients with

hypertrophic cardiomyopathy.



• The diagnosis of HCM with obstruction is based on resting gradient of more than 30mmHg or provocation gradient greater than 50mmHg , that correlates with the time of onset and duration of contact between mitral leaflet and septum ,the earlier and the longer the contact, the higher the pressure gradient .

• Obstruction in HCMObstruction in HCM

Continuous wave Doppler Continuous wave Doppler examinations are performed examinations are performed

from the apical window to from the apical window to estimate the LV outflow tract estimate the LV outflow tract

pressure gradient pressure gradient

•

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Sirak T E , Sherrid M V Chest 2008;133:1243-1246

Doppler Echocardiographic tracing showing a resting LVOT velocity of 4.8

m/s corresponding to a gradient of 92 mmHg.

• The typical appearance of the HCM Doppler signal is late-peaking and frequently referred to as “dagger-shaped”

• Doppler “dagger-shaped” late-peaking signal of intracavitary gradient in hypertrophic cardiomyopathy accentuated by Valsalva response and by inhaled amyl nitrite. At rest, the velocity is 3.0 m/s (gradient, 36 mm Hg)

and increases to 3.5 m/s (gradient, 50 mm Hg) during Valsalva and to 4.7 m/s (gradient, 88 mm Hg) after inhalation of

• amyl nitrite.

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Apical long axis view with colour flow mapping in a patient with hypertrophic cardiomyopathy and a midventricular gradient and an apical aneurysm.



Other studies Electrocardiography and holter monitoring o An abnormal ECG in the young is a sensitive marker

of early disease expression .o The most frequent ECG changes areLeft atrial enlargementRepolarization abnormalities, and pathologic Q waves,

most commonly in the inferolateral leads.Voltage criteria for left ventricular hypertrophy

(nonspecific).Giant negative T waves in the mid-precordial leads

(apical hypertrophy) . Some patients have a short PR interval with a slurred

QRS upstroke, not usually associated with Wolff-Parkinson-White syndrome.

• oAmbulatory electrocardiographic monitoring frequently reveals premature ventricular complexes (88%), Nonsustained ventricular tachycardia (25% to 30%) and supraventricular tachyarrhythmia's (30% to 40%) such as atrial fibrillation and flutter.

o Sustained ventricular tachycardia is rare, but can occur in patients with apical left ventricular aneurysms

o. The frequency of all arrhythmias during 48-hour ambulatory electrocardiographic monitoring is age related.

o supraventricular arrhythmias are more common in patients with outflow tract obstruction.

Magnetic Resonance Imaging Magnetic Resonance Imaging

• Magnetic resonance imaging is of particular value in HCM when 2-D echo is unable to document the site and extent of hypertrophy, especially in apical ,basal free wall and antrolateral paterrns of HCM.

Cardiac Catheterization Cardiac Catheterization

• Catheterization is indicated when planning therapy (e.g., in severe mitral regurgitation) and in excluding coronary atherosclerosis in older patients with chest pain.

• • Pressure tracings demonstrating the Brockenbrough–Braunwald–

Morrow signAO = Descending aorta; LV = Left ventricle; ECG = Electrocardiogram.After the third QRS complex, the ventricle has more time to fill. Since there is more time to fill, the left ventricle will have more volume at the end of diastole (increased preload). Due to the Frank–Starling law of the heart, the contraction of the left ventricle (and pressure generated by the left ventricle) will be greater on the subsequent beat (beat #4 in this picture). Because of the dynamic nature of the outflow obstruction in HCM, the obstruction increases more than the left ventricular pressure increase. This causes a fall in the aortic pressure as the left ventricular pressure rises (seen as the yellow shaded area in the picture).

• Left ventriculography may show a septal

bulge encroaching on the left ventricular outflow tract during systole together with systolic anterior motion of the anterior mitral valve leaflet and mitral regurgitation. In patients with hypertrophy confined to the left ventricular apex, the ventricular angiogram may show a characteristic spade-shaped appearance in the right anterior oblique projection.

Radionuclide Scanning and Radionuclide Scanning and PET PET

• Reversible perfusion defects are likely to be associated with increased risk of SCD

• The characteristic radio ventriculographic findings of HCM include

abnormal diastolic filling.

delayed peak filling

prolonged isovolumic relaxation .

• Cardiomyopathy ”hypertrophic“. Stress (top row) and rest (bottom row) technetium-99m Sesta-2-methoxy-isobutyl-isonitrile (MIBI) perfusion images of hypertrophic cardiomyopathy shows a reversible septal perfusion defect that is not related to coronary obstruction. The septum is markedly thickened (4 cm on the echocardiogram).

Elevated plasma BNPElevated plasma BNP– Highest concentrations occur in pts with LVOT Highest concentrations occur in pts with LVOT

obstructionobstruction– Increased ventricular expression is due to Increased ventricular expression is due to

obstruction, diastolic dysfunction and other obstruction, diastolic dysfunction and other factors.factors.

Risk Assessment for Sudden Risk Assessment for Sudden Cardiac Death in HCMCardiac Death in HCM

Numerous clinical features have been proposed as markers of increased risk of sudden death the most readily determined in clinical practice include:

1. Previous cardiac arrest 2. Unexplained syncope (SPECIALY EXERIONAL ).3. Family history of premature sudden deaths4. Nonsustained ventricular tachycardia during 48-hour

ambulatory ECG monitoring 5. An abnormal blood pressure response during exercise (failure

of blood pressure to rise appropriately by more than 20 to 30 mm Hg from baseline)

6. severe left ventricular hypertrophy (maximum wall thickness oF30 mm) .

The risk associated with all these risk factors is greatest in younger patients .

MANAGEMENT OF MANAGEMENT OF OBSTRUCTIVE HCMOBSTRUCTIVE HCM

• General Principles■ All first-degree relatives should undergo screeningwith echocardiography, and younger affected membersof the family should have genetic counseling if they plan

to have a family.■ For adults, screening should be repeated every 5

years, while children and those participating in competitive athletics should be screened every 12-18 months.

■ HCM patients should avoid competitive athletics or other types of strenuous activity, but may participate in low-level aerobic exercise to promote general cardiovascular health.

Antibiotics should be given prophylactically according to the AHA guidelines before surgical and dental procedures to prevent infective endocarditis.

■ Dehydration should be avoided.

■ Holter monitoring should be performed for 24-48 hours to detect ventricular arrhythmias and for risk stratification.

■ Pure vasodilators, high-dose diuretics and positive inotropes should be avoided as they may exacerbate left ventricular outflow obstruction.

Pharmacological therapy Pharmacological therapy β-Blockers, Calcium Blockers, and /or Disopyramide• For patients with obstructive cardiomyopathy and

symptoms, first-line pharmacologic therapy should be negative inotropic agents.

• β-Blockers β-Blockade with large dosages in the range of 200 to 400 mg propranolol or equivalent per day is a good first choice .relieve symptoms in about 50% of patients by slowing the heart rate, which allows a longer diastolic filling time and decreases myocardial oxygen consumption, thus reducing myocardial ischemia and

left ventricular outflow tract obstruction through a direct negative inotropic effect.

• If this does not adequately decrease the intraventricular gradient and control symptoms, calcium channel blockers may be added ,usually verapamil in dosages of 240 to 320 mg per day. Care must be taken when prescribing calcium channel blockers for patients with large outflow tract obstruction, because acute homodynamic deterioration may occur because of peripheral vasodilatation.

• Disopyramide, a class I antiarrhythmic agent with strong negative inotropic properties, may also be used to treat HCM, especially in patients with outflow tract obstruction, however, it has significant side effects, anticholenergic properities ,possibility of augmenting AV nodal conduction in presence of AF so only used in symptomatic patient when more definitive procedure is being planned .

Non pharmacological therapy Non pharmacological therapy

Surgery should be considered in all patients with outflow tract gradients greater than 50 mm Hg (resting or with provocation) and symptoms refractory to medical therapy .

septal myectomy ;((Morrow procedure ))

• The outflow tract is effectively widened; thereby abolishing the gradient and eliminating systolic anterior motion mediated mitral regurgitation with infrequent <5%)complications and mortality.

Alcohol Septal Ablation for HCM

• used for patients who are not candidates for septal myectomy

Dual-Chamber Pacing in HCM

Pacing was advocated as another means of relieving outflow obstruction.

The proposed mechanism for the beneficial effects of pacing include optimization of atrioventricular synchrony, alteration of ventricular activation sequence (i.e. apex to base), and potentially long-term remodeling to widen the outflow tract .

NON OBSTRUCTIVE HCMNON OBSTRUCTIVE HCM

• BB and /or verapamil .

• Diuretics (congestion).

• Transplantation.

• ACE , diuretic ,dig ; for end stage HCM.

HCM WITH AF HCM WITH AF

• DCC (direct current cardioversion) for heamodynamicaly unstable patient

• BB/OR verapamil for rate control • Disopyramid or sotalol to maintain NSR• Amiodaron for refractory cases . • DDD with nodal ablation in patient with

persistent symptom with failed medical therapy • Anticoagulation for chronic AF .

HCM with VT HCM with VT

• Amiodaron or AICD (automatic implantable cardioverter defibrillator) for NSVT in high risk patient.

• AICD with pacing capabilities for cardiac arrest survivors .

• Transplantation for refractory VT.

Treatment of hypertrophic cardiomyopathy according to Treatment of hypertrophic cardiomyopathy according to clinical presentationclinical presentation

DDD pacing: dual chamber pacing; LVMM: left ventricular myotomy and myectomy; RNA: radionuclide angiography; RFA: radiofrequency ablation; Isch: ischemia; SVT: supraventricular tachycardia; VT: ventricular tachycardia.

Management algorithm of Management algorithm of hypertrophic cardiomyopathyhypertrophic cardiomyopathy

• ACC/AHA guidelines for management of patients with

ventricular arrhythmias and prevention of sudden cardiac death

Recommendations• Class I ICD therapy should be used for treatment in patients with

hypertrophic cardiomyopathy (HCM) who have sustained VT and/or VF and who are receiving chronic optimal medical therapy and who have reasonable expectation of survival with a good functional status for more than 1 year. (Level of Evidence: B)

• Class II a 1. ICD implantation can be effective for primary prophylaxis against SCD in patients with HCM who have one or more major risk factor for SCD and who are receiving chronic optimal medical therapy and in patients who have reasonable expectation of survival with a good functional status for more than 1 year. (Level of Evidence: C)

2. Amiodarone therapy can be effective for treatment in patients with HCM with a history of sustained VT and/or VF when ICD is not feasible. (Level of Evidence: C)

• Class II b 1. EP testing may be considered for risk assessment for SCD in patients with HCM. (Level of Evidence: C)

2. Amiodarone may be considered for primary prophylaxis against SCD in patients with HCM who have one or more major risk factor for SCD (See Table 5), if ICD implantation is not feasible. (Level of Evidence: C)

Supravalvular obstruction Supravalvular obstruction

• It involves

supravalvular aortic stenosis and congenital LVOT lesions (coartication of the aorta , aortic arch interruption ,aortic arch hypoplasia …..)

Supravalvular aortic stenosis (SVAS)

Supravalvular aortic stenosis (SVAS) is a fixed form of congenital left ventricular outflow tract (LVOT) obstruction that occurs as a localized or a diffuse narrowing of the ascending aorta beyond the superior margin of the sinuses of Valsalva.

It accounts for less than 7% of all fixed forms of congenital LVOT obstructive lesions.

Supravalvular aortic stenosis may occur sporadically, as a manifestation of elastin arteriopathy, or as part of Williams syndrome (also known as Williams-Beuren syndrome), a genetic disorder with autosomal dominant inheritance.













• Two-dimensional suprasternal echocardiography image of supravalvular aortic stenosis.

• Aortogram of a patient with supravalvular aortic stenosis and dilated sinus of Valsalva.

Supravalvular aortic stenosis has 3 commonly recognized morphologic forms.

1) An external hourglass deformity with a corresponding luminal narrowing of the aorta at a level just distal to the coronary artery ostia is present in 50-75% of patients.

2) In approximately 25% of patients, a fibrous diaphragm is present just distal to the coronary artery ostia.

3) In fewer than 25% of patients, a diffuse narrowing along a variable length of ascending aorta is present .

Similarly, the following 3 anatomic subtypes of coronary lesions have been recognized in supravalvular aortic stenosis

1)Circumferential narrowing of the left coronary ostium

1)Ostial obstruction due to fusion of the aortic cusp to the supravalvular ridge

1)Diffuse narrowing of the left coronary artery

• Supravalvular stenosis is a progressive

lesion

• The risk of sudden cardiac death, including an operated patients, is 1 case per 1,000 patient /year and is 25-100 times higher than in the normal population.

• Patients with supravalvular aortic stenosis are vulnerable to cardiac arrest or significant hemodynamic instability during induction of anesthesia and cardiac catheterization

Clinical assessment Clinical assessment • History

Symptoms caused by supravalvar aortic stenosis (SVAS) usually develop in childhood and only rarely do so in infancy; however, some patients may develop symptoms in the second or third decade of life.

• Most pediatric patients present because of a heart murmur or the features of Williams syndrome (elfin facies, mental retardation, "cocktail party" personality, gastrointestinal problems , systemic hypertension, hypercalcemia and progressive joint

involvement) .

• Dyspnea on exertion, angina, and syncope develop in the course of the disease if untreated. – These symptoms indicate at least a moderate

degree of left ventricular (LV) outflow tract (LVOT) obstruction.

– Because of the coronary artery involvement, angina may arise early and more often than in other obstructive LVOT lesions.

– Because of the risk of sudden death in supravalvular aortic stenosis, the development of angina and syncope should prompt immediate investigation.

• Physical examination

Asymmetric upper extremities pulses:

Discrepancies between carotid pulsations and upper extremities pulses and blood pressure are the characteristic clinical findings of supravalvular aortic stenosis. The jet of blood flow from supravalvular aortic stenosis demonstrates preferential trajectory into brachiocephalic (innominate) artery (i.e., Coandă effect), which accounts for the discrepancies.

Precordium: The apex is usually hyperdynamic, and displaced laterally and inferiorly because of ventricular hypertrophy.

A thrill in the suprasternal notch is usually felt because of the trajectory of the blood flow jet from supravalvular aortic stenosis.

Auscultation: Heart sounds:

The first heart sound is generally normal.

A narrowly split, single, or paradoxically split second heart sound

A fourth heart sound are present in severe supravalvular aortic stenosis.

An ejection click is absent in supravalvular

aortic stenosis

Heart murmurs:. The characteristic systolic murmur of supravalvular aortic stenosis is

crescendo-decrescendo in shape, low pitched, and best heard at the base of the heart sited higher than in valvular aortic stenosis. It mainly radiates to the right carotid artery and tends to peak during the last two thirds of the ventricular systole if the obstruction is severe.

A high-pitched, short, early diastolic aortic regurgitation murmur is uncommon in supravalvular aortic stenosis

Laboratory Workup Laboratory Workup • Echocardiography:

The anatomic diagnosis of supravalvular aortic stenosis can be made from 2-dimensional echocardiography that uses multiple views, including Parasternal, apical long-axis, and suprasternal

In supravalvular aortic stenosis with hourglass deformity and diffuse hypoplasia, the diameter of the ascending aorta is smaller than that of the aortic root.

In supravalvular aortic stenosis with fibrous diaphragm, the external ascending aortic diameter is normal, although echogenic membrane is commonly observed above the sinuses of Valsalva.

Turbulent color flow mapping indicates the site of hemodynamically significant obstruction and can reveal coronary Ostial stenosis, the incidence of which is high in SVAS.

Doppler peak gradient overestimates and, therefore, does not predict catheter-measured gradient well in patients with supravalvular aortic stenosis and may not be reliable in assessing its severity and guiding the need for intervention.

• MRI: This can provide high definition of

the lesion, although obtaining an MRI of infants and young children may require sedation, which carries risk of sudden death and, therefore, should be undertaken with close supervision and administered by an experienced anesthesiologist.

• Alternatively, multislice CT with angiography, which can generate high-resolution images of the lesion within seconds, can be used. However, this process exposes the child to radiation.

• Chest radiography: Cardiac silhouette may be variably increased, and the ascending aorta may be asymmetrically dilated. The presence of both findings indicates hemodynamically significant supravalvular aortic stenosis.

• Electrocardiography: Electrocardiography usually reveals

left ventricular hypertrophy, depending on the severity of stenosis. ST-T segment changes may be present with involvement of coronary ostia and the coronary arteries.

• Genetic evaluation: Obtain a genetic evaluation for patients

with supravalvular aortic stenosis to discern the diagnosis of Williams syndrome, which is often associated with supravalvular aortic stenosis.

• Cineangiography: A biplane left ventriculogram and an Aortogram

can reveal the morphology of supravalvular narrowing, stenosis of the arch vessels, abnormalities of aortic root, and dilated coronary arteries .

Right ventricular or pulmonary arterial angiography should be performed simultaneously to demonstrate the presence of peripheral pulmonary artery stenosis, particularly in Williams syndrome

Mangment Mangment

• Drug therapy has no role in the treatment of symptomatic patients with supravalvar aortic stenosis (SVAS). Precautions to prevent bacterial endocarditic are necessary.

Surgery is the primary treatment for supravalvar aortic stenosis (SVAS).

Children and adolescents with catheter peak-to-peak (or Doppler mean) gradient of 50 mm Hg or more should have surgical intervention similar to what is indicated for valvular aortic stenosis.

(class I).

• A symptomatic patients who have

developed ST/T-wave changes over the left precordium on ECG at rest or with exercise should also be considered for surgical intervention.

coartication of the aortacoartication of the aortaCoarctation of the aorta occurs in approximately 6% to

8% of patients with congenital heart disease.

As with most left-sided obstructive lesions, coarctation occurs more commonly in males than in females, with a male: female ratio ranging from 1.27 to 1.74

Coarctation of the aorta is usually a discrete stenosis of the upper thoracic aorta at the point of the insertion of the ductus arteriosus . Most coarctations, therefore, are properly described as juxtaductal in location.

• The lesion is most often discrete, but it may

be long segment or tortuous in nature. In infants, particularly those with associated left ventricular outflow obstruction or a ventricular septal defect, there may be diffuse hypoplasia of the transverse aortic arch and isthmus proximal to the discrete coarctation

• Simple coarctation describes coarctation of the aorta occurring without important intracardiac lesions, with or without a patent ductus arteriosus

• The term complex coarctation describes coarctation with important associated intracardiac pathology

• A large ventricular septal defect the most common associated lesion. Ventricular septal defects associated with coarctation include the peri-membranous, muscular, or malalignment types. A malalignment ventricular septal defect may occur with posterior deviation of the conal septum and significant left ventricular outflow tract obstruction.

• A bicuspid aortic valve occurs in 85% of patients with coarctation

• Patients with Turner syndrome (XO) frequently present with coarctation of the aorta and a BAV

• The association of multiple left-sided obstructive lesions with coarctation has been referred to as Shone syndrome ( constitutes a challenging group of lesions when treatment is required in infancy).

• Coarctation of the aorta is also an important

component of the hypoplastic left heart syndrome.

• Extracardiac vascular anomalies are present in many patients with coarctation. The most important of these anomalies include variations in the brachiocephalic artery anatomy, a collateral arterial circulation, and berry aneurysms of the circle of Willis.

• The clinical presentation of coarctation of the aorta generally follows one of three patterns:

An infant with congestive heart failure, A child or adolescent with systemic arterial

hypertension, A child with a heart murmur.

• When coarctation presents in infancy, it often presents as a catastrophic illness. Congestive heart failure and shock may occur suddenly as the ductus arteriosus closes.

• A large proportion of these infants have a

complex coarctation, with important associated lesions such as a ventricular septal defect or aortic stenosis In an infant with severe coarctation associated with a large ventricular septal defect, acute heart failure, shock, and acidosis often develop suddenly at approximately 8 to 10 days of life.

• Multiorgan system failure, particularly renal failure and/or necrotizing enterocolitis, and death occur rapidly unless definitive medical and surgical interventions are provided immediately

Physical Examination Physical Examination

• Adult unoperated patients almost present with systemic arterial hypertension measured in the upper extremities. A patient with systemic arterial hypertension should have upper and lower extremity arterial blood pressures measured on physical examination.

• A normal patient should have an increase of 5 to 10 mm Hg in systolic blood pressure in the lower extremities compared with the upper extremities, absence of this increase or presence of a decrease in systolic blood pressure in the lower extremities should prompt further investigation to rule out coarctation of the aorta.

• Moreover, we strongly recommend that all patients with systemic hypertension should have a brachial and femoral pulse timing and amplitude evaluation on physical examination; this can easily be done by palpating the brachial and femoral pulses simultaneously.

• Presence of a delay or decrease in amplitude of the femoral pulse should prompt further investigation.

• . Auscultation over the left upper back will often reveal a parascapular systolic or continuous murmur (depending on the number and degree of collaterals). Patients with a coexistent BAV will have an ejection sound and midsystolic murmur at the apex and base, respectively .

• Characteristic rib notching is often present on chest x-ray or CT and is indicative of extensive arterial collateral formation bypassing the area of coarctation; a characteristic "3" sign is often also seen on chest x-ray.

Transthoracic Doppler echocardiography for initial imaging and hemodynamic evaluation in suspected aortic coarctation:

Evaluation for coarctation is best done via the suprasternal notch view and should include continuous-wave Doppler assessment of the distal aortic arch and isthmus .

Hemodynamically significant coarctation will have a typical continuous-wave Doppler profile demonstrating continuing anterograde flow tapering off during diastole

• . A 20 mm Hg peak instantaneous gradient at rest or on provocation with exercise may be indicative of a significant coarctation.

• Echocardiography should also be used to rule out commonly associated lesions such as BAV and dilation of the ascending aorta.

• Recall that in the presence of an extensive

bypassing collateral network, the systolic and diastolic gradients are less reliable, and more accurate anatomic imaging is needed .

• MR and CT angiography of the chest with 3-dimensional reconstruction clearly demonstrate the degree and extent of coarctation and collateral formation

• MR angiogram of a patient with complete interruption of the aorta (white arrow) as viewed from the lateral orientation. Note the extensive collateral network (*) of intercostals arteries bypassing the site of interruption.

• Untreated, coarctation of the aorta has a

poor natural history. The most common causes of death In Campbell’s necropsy study were congestive heart failure (26%), aortic rupture (21%), bacterial endocarditis (18%), and intracranial hemorrhage (12%) Given such a poor prognosis , it is apparent that intervention is indicated in virtually all patients with coarctation of the aorta.

TreatmentTreatment For neonates:• Infusion of prostaglandin E1 to reopen the constricted

duct's arteriosus. • TTT of HF.• Surgical repair• No role for balloon dilatation at this age group. for infants and children:• Balloon dilatation is effective.• Surgical repair for arch hypoplesia For adults:• Surgical repair with or without aortic valve replacement is

the procedure of choice.• Balloon dilatation with or without stenting is also effective

stratgy.

Mild/mod stenosis sever stenosis

SAS

1-2/6 MSM at LUSB/RUSB may radiate to carotids, non

sustained/non displaced LV impulse. EDM at LLSB in

patients with AR.

>3/6 late-peaking MSM at LUSB/RUSB radiating to carotids. LV impulse laterally displaced and sustained. Diminished and

delayed arterial pulses. S4 gallop is common. EDM at LLSB in patients with

AR.

BAV

1-2/6 MSM at LUSB/RUSB may radiate to carotids. ES heard at

apex/LLSB if age <40 years. Non sustained/non displaced LV impulse. EDM at LLSB in

patients with AR.

>3/6 late-peaking MSM at LUSB/RUSB radiating to carotids. LV impulse laterally displaced and sustained. Diminished and delayed arterial pulses. No ES. S4 gallop

is common. EDM at LLSB in patients with AR.

SVAS 1-2/6 MSM at RUSB often radiates to carotids. Non

sustained/non displaced LV impulse.

>3/6 late-peaking MSM at RUSB radiating to carotids. LV impulse laterally

displaced and sustained. S4 gallop is common.

Aortic coarca-tion

Absent or mild brachial to femoral pulse delay. 0-1/6

paraspinal MSM may be present.

Significantly decreased/absent and delayed femoral pulses. >2/6 paraspinal

MSM or continuous murmur. Atrophy of lower extremity musculature compared

with upper extremity.

MSM indicates midsystolic murmur; EDM, early diastolic murmur; AR, aortic regurgitation; LUSB, left upper sternal border; LLSB, left lower sternal border; RUSB, right upper sternal border; LV, left ventricle; ES, ejection sound; and S4, fourth heart sound.

Characteristic Physical Examination Findings in LVOTO