Deep vein thrombosis

A condition involving blood clots in deep veins

Deep vein thrombosis

Deep vein thrombosis of the right leg

Deep vein thrombosis (DVT) is a medical condition that occurs when a blood clot forms in a deep vein, typically in the legs. This condition can lead to serious complications, such as pulmonary embolism, if the clot dislodges and travels to the lungs.

Pathophysiology

Coagulation process in vivo

DVT is primarily caused by the formation of a blood clot in the deep veins of the leg. The process of clot formation involves the coagulation cascade, which is a series of steps that lead to the conversion of fibrinogen to fibrin, forming a stable clot. Factors contributing to clot formation include venous stasis, endothelial injury, and hypercoagulability, collectively known as Virchow's triad.

Risk Factors

Several risk factors increase the likelihood of developing DVT, including:

• Prolonged immobility, such as during long flights or bed rest
• Surgery, particularly orthopedic procedures
• Cancer and certain cancer treatments
• Hormone replacement therapy or oral contraceptives
• Pregnancy and the postpartum period
• Genetic clotting disorders
• Obesity
• Smoking

Symptoms

Diagram of lower limb veins

Symptoms of DVT may include swelling, pain, and redness in the affected leg. The leg may feel warm to the touch, and there may be visible surface veins. However, some individuals with DVT may be asymptomatic.

Diagnosis

Illustration of deep vein thrombosis

The diagnosis of DVT is typically confirmed through imaging studies such as ultrasound or venography. A blood test measuring D-dimer levels can also be used to assess the likelihood of clot formation, although it is not specific to DVT.

Complications

Saddle pulmonary embolism

The most serious complication of DVT is pulmonary embolism (PE), which occurs when a clot breaks free and travels to the lungs, potentially causing life-threatening respiratory distress. Other complications include post-thrombotic syndrome, characterized by chronic pain and swelling in the affected limb.

Treatment

Compression stockings used in DVT management

Treatment for DVT typically involves anticoagulation therapy to prevent further clotting. Common medications include heparin, warfarin, and newer oral anticoagulants such as rivaroxaban and apixaban. In some cases, thrombolytic therapy or surgical intervention may be necessary.

Prevention

Preventive measures for DVT include maintaining mobility, using compression stockings, and prophylactic anticoagulation in high-risk individuals. Lifestyle modifications such as weight management and smoking cessation are also recommended.

Related pages

• Pulmonary embolism
• Thrombophilia
• Venous thromboembolism