Deep vein thrombosis
Also called: DVT, Venous thromboembolism
A blood clot forms in a deep vein, usually in the calf or thigh. The danger is that part of the clot breaks off and travels to the lungs (pulmonary embolism).
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What happens in the body
Virchow's triad: slow blood flow, damage to the vein wall and a tendency to clot.
Causes
- Immobility (surgery, long travel, hospital stay)
- Clotting disorders
- Cancer and chemotherapy
- Pregnancy and oestrogen medicines
Risk factors
- Recent surgery, especially hip or knee
- Previous clot
- Cancer
- Pregnancy and after birth
- Combined pill or HRT
- Obesity
- Smoking
- Inherited thrombophilia
Symptoms
- Swelling of one leg
- Pain or tenderness in the calf or thigh
- Warm, red or discoloured skin
- Sometimes no symptoms
Diagnosis — tests and examinations
- Wells score
- D-dimer blood test
- Compression ultrasound of the leg veins
Treatment
Medicines and medical treatment
- Anticoagulation: apixaban, rivaroxaban, low-molecular-weight heparin or warfarin for at least 3 months
Operations and procedures
- Catheter-directed thrombolysis for massive clots
- Inferior vena cava filter when anticoagulation is impossible
Self-care, home remedies and lifestyle
- Walk and keep mobile
- Elevate the leg when resting
- Stay hydrated on long journeys
Possible complications
- Pulmonary embolism
- Post-thrombotic syndrome (chronic leg swelling and ulcers)
- Recurrence
Prevention
- Early mobilisation after surgery
- Preventive heparin and compression stockings in hospital
- Calf exercises and hydration on long flights
Outlook
Most clots resolve with anticoagulation; some people need long-term treatment.
When to see a doctor
See a doctor the same day for a swollen, painful leg. Call emergency services for chest pain or sudden breathlessness.
Sources and further reading
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