What is Vein Thrombosis?
Vein thrombosis occurs when a blood clot (thrombus) forms inside a vein, blocking or slowing blood flow. It commonly affects deep veins in the legs, known as deep vein thrombosis (DVT), but can occur in other veins as well.
What Are the Symptoms of Vein Thrombosis?
- Swelling, usually in one leg or arm
- Pain or tenderness, often starting in the calf
- Warmth and redness over the affected area
- Skin discoloration or bluish color
- Visible surface veins
In some cases, vein thrombosis may cause no symptoms but can still be dangerous.
What Causes Vein Thrombosis?
Blood clots form due to factors in Virchow’s triad: slowed blood flow, vessel injury, and increased blood clotting tendency. Common causes include:
- Prolonged immobility (e.g., long flights or bed rest)
- Injury or surgery, especially involving veins
- Certain medical conditions (cancer, heart disease)
- Pregnancy and hormonal therapies (birth control pills, hormone replacement)
- Obesity
- Smoking
- Genetic clotting disorders
How is Vein Thrombosis Diagnosed?
- Physical examination
- Ultrasound of the affected vein
- D-dimer blood test to detect clotting activity
- Venography or MRI in complex cases
How is Vein Thrombosis Treated?
- Medications
- Anticoagulants (blood thinners) such as heparin, warfarin, or direct oral anticoagulants to prevent clot growth and new clots
- Thrombolytics (clot-busting drugs) in severe cases
- Lifestyle Measures
- Compression stockings to reduce swelling and improve blood flow
- Elevating the affected limb
- Regular movement and exercise to prevent stasis
- Surgical or Interventional Procedures
- Thrombectomy to remove the clot
- Placement of vena cava filter to prevent clots traveling to the lungs (in select cases)
Complications of Untreated Vein Thrombosis
- Pulmonary embolism (PE) when a clot breaks loose and blocks lung arteries, a life-threatening emergency
- Post-thrombotic syndrome causing chronic pain and swelling in the limb
- Recurrence of thrombosis