Deep vein thrombosis
Deep vein thrombosis is thrombus in the deep veins of the leg or pelvis, proximal when the popliteal, femoral, or iliac veins are involved and distal when confined to the calf veins. It is diagnosed by Wells pretest probability, D-dimer for unlikely cases, and compression ultrasound showing a noncompressible vein, and treated with anticoagulation whose length is set by whether the clot was provoked.
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What this article covers
- Overview
Definition: deep vein thrombosis (DVT) is thrombus in the deep veins of the pelvis and legs; it is proximal when the popliteal, femoral, or iliac veins are involved and distal when only the calf…
- Epidemiology
Common: a first VTE occurs in 1 to 2 per 1000 person-years, and VTE affects 1 in 100 people older than 70.
- Risk factors
Previous VTE: one of the strongest predictors of a new event.
- Pathophysiology
Virchow triad: reduced or turbulent flow, vessel wall injury, and prothrombotic blood changes act together.
- Clinical features
Hallmark, acute unilateral leg swelling: fullness, pain, and tenderness developing over days, often with warmth and erythema; calf asymmetry over 3 cm measured 10 cm below the tibial tuberosity is more specific.
- Differential diagnosis
Acute limb ischemia: sudden severe pain with pallor and pulselessness (the 6 Ps), not a swollen warm leg (acute limb ischemia).
- Diagnosis
Establish the diagnosis by compression duplex ultrasound, triaged by the Wells DVT score: DVT is confirmed by a noncompressible vein segment with reduced or absent Doppler flow; pretest probability…
- Management
First, look for phlegmasia cerulea dolens: a threatened limb needs emergent catheter-directed thrombolysis, thrombectomy, or fasciotomy in addition to anticoagulation.
- Complications
Pulmonary embolism, the life-threatening complication.
- Prognosis
Good with prompt anticoagulation, usually without hospitalization.
- Prevention
Score every medical inpatient with the Padua Prediction Score: a score of 4 or more (11% VTE risk) without contraindication gets enoxaparin 40 mg SC once daily (30 mg if creatinine clearance is below…
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Related articles
- Pulmonary embolism
Pulmonary embolism is thrombus, usually from a lower-extremity deep vein thrombosis, obstructing the pulmonary arterial circulation and causing V/Q mismatch, right ventricular strain, and hypoxemia. Diagnosis follows Wells criteria (with PERC in low-risk patients) to sequence D-dimer, CT pulmonary angiography, and V/Q scanning, and management is risk-stratified anticoagulation escalating to thrombolysis or embolectomy for hemodynamic instability.
- Post-thrombotic syndrome
Post-thrombotic syndrome is chronic venous insufficiency developing after deep vein thrombosis, from valvular damage and residual obstruction. It causes chronic limb pain, swelling, skin changes, and sometimes ulcers, is graded by the Villalta score, and is managed with compression, exercise, and, for severe iliofemoral disease, venous stenting.
- Superficial venous thrombosis
Superficial venous thrombosis is thrombosis of a superficial vein, presenting as a tender, warm, palpable cord, often in a varicose vein. Once considered benign, extensive disease near the deep system carries a real risk of extension to deep vein thrombosis, so evaluation includes ultrasound and treatment may include prophylactic-dose anticoagulation.
- Cancer-associated venous thromboembolism
Deep vein thrombosis or pulmonary embolism occurring in a patient with active malignancy, driven by tumor-derived procoagulant activity plus stasis and vascular injury. Diagnosis is confirmed by compression ultrasonography or CT pulmonary angiography, and first-line treatment is apixaban, rivaroxaban, or low molecular weight heparin continued while cancer is active.
- Thrombophilias: an overview
Thrombophilias are inherited or acquired hypercoagulable states that predispose to venous, and in some acquired conditions arterial, thrombosis. Testing is selective and deferred until the patient is off anticoagulation and remote from acute clot, because acute thrombosis, heparin, warfarin, and estrogen all distort results, and most results do not change acute management except in antiphospholipid syndrome.