mr. naresh govindarajanthran vascular surgery hkl
TRANSCRIPT
Deep vein thrombosis
Mr. Naresh
Govindarajanthran
Vascular Surgery
HKL
Venous anatomy of the lower limbs
Superficial system
Long saphenous vein
Short saphenous vein
Deep system
Femoral veins
Popliteal veins
Calf veins
Virchow’s triad
Abnormalities of blood flow (stasis)
Abnormalities of blood (coagulation
disorders)
Injury to the vessel wall
Risk factors
Age
Cancer
Smoking
Coagulation disorders
Obesity
Oestrogen substitution
Surgery (hip or knee arthroplasty, cancer surgery in the
abdominopelvic area)
Immobilization
Previous DVT
Hypercoagulability
Inherited
Common
Factor V Leiden
Prothrombin gene mutation (G20110A)
Rare
Antithrombin deficiency
Protein S deficiency
Protein C deficiency
Dysfibrinogenemia
Homozygous homocystinuria
Acquired
Age
Surgery and trauma
Immobilization
Malignant disease
Previous venous thromboembolism
Pregnancy and puerperium
Oral contraceptive and hormone replacement therapy
Antiphospholipid antibodies
Unknown (Probably Multifactorial)
Elevated levels of factor VIII, IX, and XI and fibrinogen
Diagnosis
Combination of
clinical assessment
laboratory studies
imaging
Signs and Symptoms
Symptoms
Calf pain and oedema of the calf or the whole leg
may be asymptomatic especially acute
pulmonary embolism
Signs
Calf tenderness with pitting oedema
massive DVT
cyanotic-phlegmasia cerulae dolens
Phlegmasia
Lab investigation
D-dimer
rapid, simple and inexpensive test
predictive value of negative D-dimer
improves greatly when used as part of an
algorithm
may be raised in inflammation, surgery or
cancer
Duplex ultrasound
Femoropopliteal vein
Sensitivity 98.7%
Specificity 100%
Below knee veins
Sensitivity 70%
Specificity 60%
Compressibility
Diagnosis
**A score of 2 or more indicates probability of DVT is high
Wells et al. NEJM 2003; 349: 1227-35
Primary prevention
Physical methods
postoperative early ambulation
graduated compression stockings
intermittent pneumatic compression
Anticoagulation
UFH
LMWH
vitamin K antagonist
Long term prevention
Warfarin started simultaneously with
heparin
INR 2.0-3.0
stop heparin after 5-7 days
LMWH with warfarin for 3 months prevents
recurrence in 95% and has a risk of severe
bleeding of 1% Hull et al. N Eng J Med 1990;
322:1260-4
Questions asked?
LMWH or UFH?
LMWH
100IU/kg twice daily or 150IU/kg daily
as effective as bolus and infusion UFH
LMWH
more predictable dose response relationship (no need
monitoring)
longer half life
lower risk of HIT
lower risk of osteoporosis
caution with renal failure as LMWH is excreted via kidneys
Dolovich et al Arch Intern Med 2000; 160:180-88
Newer agents
Fondaparinaux
synthetic specific antifactor Xa
pentasaccharide with the same active site
as heparin
doesn’t cross react with PF-4
(development of HIT)
Newer agents
Direct thrombin inhibitors (DTI)
recombinant hirudin, lepirudin, argatroban
intravenous administration
monitored with APTT
Ximelagatan
oral DTIs
predictable bioavailability and does not require monitoring
transient elevation of liver enzymes but normalizes after 4
months
rare cases of fulminant hepatic flexure
How long?
Duration
Proximal DVT related to reversible and
time-limited risk factors (surgery,
trauma,long haul airplane flights)
3 months of warfarin
First episode of idiopathic DVT
6-12 months of warfarin
Duration
DVT and mild thrombophilic conditions
(protein C and S deficiency, heterozygous
factor V Leiden, hyperhomocysteinaemia)
6 months of warfarin
DVT with stronger thrombophilias
(antithrombin deficiency, anti-phospholipid
antibodies, homozygous factor V Leiden)
indefinite anticoagulation
Thrombolysis required?
Thrombolysis
Who may benefit
Required in limb threatening DVT
Possibly young patients with extensive iliofemoral DVT
systemically (ineffective) or via catheter directed
complete of substantial resolution of thrombus possible in 85%
with DVT <10days
diminishes pain, swelling and valve destruction but no effect on
incidence of post phlebitic syndromes
has an increased risk of bleeding
Contraindications
Recent surgery (<7days) esp neurosurgery
and ophtalmic surgery
Bleeding daisthesis
Haemorrhagic stroke within 2 months
Pregnancy
Thrombolysis
Streptokinase
Urokinase
rTPA
has an increased risk of bleeding
currently infrequent due to cost consideration, contra-indication to
thrombolysis, perceived high risk of thrombolytic agents
Role of Surgery or
Percutaneous Mechanical
Thrombectomy
Surgical ThrombectomyInvasive
Blood loss
does not obviate the need for
anticoalgulation
must be done within the first 3 to 7 days
Role
young patients with isolated iliac
thromboses
phlegmasia cerulae dolens
Percutaneous Mechanical
Thrombectomy
Rotating devices
Venturi effect (Angiojet device)
Results are poor
Limited to patients with contraindications
to
anticoagulations
thrombolysis
IVC filters?
IVC filters
Effective in preventing short term incidence
of pulmonary embolism but not mortality
THROMBOGENIC
doubles the recurrence risk
IVC filters
Should be used in
contraindications to anticoagulants
recurrent pulmonary embolism despite
adequate anticoagulation
chronic thromboembolic pulmonary
hypertension
Conclusion
diagnosis is a combination of clinical,
laboratory and imaging.
mainstay of treatment is anticoagulation
limited role of IVC filters
duration of anticoagulation depends on the
cause