DVT

Deep Vein Thrombosis (DVT)

Deep Vein Thrombosis (DVT) is a medical condition that occurs when a blood clot forms in a deep vein, usually in the legs. This condition can lead to serious complications if not diagnosed and treated promptly.

Pathophysiology

DVT is primarily caused by the formation of a blood clot in the deep veins of the body. The Virchow's triad, which includes stasis of blood flow, endothelial injury, and hypercoagulability, is often used to describe the pathophysiological mechanisms leading to thrombosis.

Stasis of Blood Flow

Stasis, or the slowing of blood flow, can occur due to prolonged immobility, such as during long flights or bed rest. This can lead to the accumulation of clotting factors and the formation of a thrombus.

Endothelial Injury

Damage to the endothelial lining of blood vessels can trigger the coagulation cascade, leading to clot formation. This can occur due to trauma, surgery, or inflammation.

Hypercoagulability

Certain conditions, such as Factor V Leiden mutation, pregnancy, or cancer, can increase the tendency of blood to clot, contributing to the risk of DVT.

Risk Factors

Several risk factors are associated with the development of DVT, including:

• Prolonged immobility (e.g., long flights, hospitalization)
• Recent surgery or trauma
• Cancer and cancer treatments
• Hormone replacement therapy or oral contraceptives
• Pregnancy and the postpartum period
• Genetic predispositions (e.g., Factor V Leiden mutation)

Symptoms

The symptoms of DVT can vary, but common signs include:

• Swelling in the affected leg
• Pain or tenderness in the leg, often starting in the calf
• Red or discolored skin on the leg
• A feeling of warmth in the affected leg

Diagnosis

The diagnosis of DVT is typically confirmed through imaging studies, such as:

• Doppler ultrasound: A non-invasive test that uses sound waves to visualize blood flow in the veins.
• D-dimer test: A blood test that measures a substance released when a blood clot breaks up. Elevated levels may indicate the presence of an abnormal clot.
• Venography: An invasive test that involves injecting a contrast dye into a large vein and taking X-rays to visualize the veins.

Treatment

The primary goals of DVT treatment are to prevent the clot from growing, to prevent a pulmonary embolism, and to reduce the risk of recurrence. Treatment options include:

Anticoagulation

• Heparin: An anticoagulant that is often used initially to prevent further clotting.
• Warfarin: An oral anticoagulant used for long-term management.
• Direct oral anticoagulants (DOACs): Such as rivaroxaban and apixaban, which are increasingly used due to their ease of use and predictable effects.

Thrombolysis

In certain cases, thrombolytic therapy may be used to dissolve the clot, especially in severe cases or when there is a risk of limb loss.

Compression Stockings

Graduated compression stockings may be recommended to reduce swelling and prevent post-thrombotic syndrome.

Complications

One of the most serious complications of DVT is pulmonary embolism (PE), which occurs when a part of the clot breaks off and travels to the lungs. This can be life-threatening and requires immediate medical attention.

Prevention

Preventive measures for DVT include:

• Regular movement and exercise, especially during long periods of immobility
• Use of compression stockings during travel
• Prophylactic anticoagulation in high-risk patients, such as those undergoing surgery

See Also

• Pulmonary embolism
• Venous thromboembolism
• Factor V Leiden

References

• Centers for Disease Control and Prevention - DVT
• National Heart, Lung, and Blood Institute - DVT