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What is Thrombosis?

What is Thrombosis?

Thrombosis is the formation of a blood clot, known as a thrombus, within a blood vessel causing a partial or total obstruction; it prevents blood from flowing normally through the circulatory system









When the thrombus flows through the body, it can harm important organs such as the brain, heart, lungs, or leg arteries. It blocks blood flow, serious health issues can arise, such as stroke, heart attack, or pulmonary embolism.

Two key issues that arise include:

See how blood clots form:

Video Via Vascular Cures

What is deep vein thrombosis?

Deep vein thrombosis is the most common form of thrombosis. It is a blood clot in a major vein, usually in the leg.

Leg diagram

Signs and symptoms of DVT include:

  • Discomfort, heaviness, pain aching, throbbing, itching, or warmth in the legs
  • Skin changes in the leg, such as discoloration, thickening, or ulceration
  • Swelling of the legs, ankles, or feet

Post-thrombotic syndrome (PTS) develops in at least half of patients with a DVT. It involves chronic leg swelling, calf pain, calf heaviness/fatigue, skin discoloration, and/or venous ulcers in the affected limb characterize PTS. Quality of life is significantly impaired in patients with PTS.

What is a pulmonary embolism?

A pulmonary embolism a blood clot that travels to the lungs.

Pulmonary embolism (PE) is a complication from DVT.

Symptoms and signs of PE include:

  • Sudden shortness of breath
  • Chest pain
  • Coughing up blood
  • Rapid or irregular heart rate

What are the Risk Factors?

Risk factors that contribute to thrombosis include:

  • Immobilization
  • Hypercoagulability
  • Vessel wall damage
  • Age
  • Surgery (especially orthopedic surgery and total knee replacement)
  • Cancer
  • Heredity (including the Factor V Leiden genetic mutation)
  • Pregnancy
  • Increased estrogen levels (due to oral contraception or hormone replacement therapy)
  • Obesity
  • Smoking
  • Crohn's Disease    

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