Pathophysiology of thrombosis and embolism Flashcards
What is thrombosis?
Thrombosis is the formation of a blood clot (thrombus) within a blood vessel, which can obstruct blood flow.
What are the key steps in thrombosis formation?
Endothelial injury → Damage to the vessel wall exposes collagen, activating platelets.
Platelet activation & aggregation → Platelets adhere and release pro-thrombotic factors.
Coagulation cascade activation → Fibrin forms, stabilizing the platelet plug into a thrombus.
Growth or resolution → The thrombus may grow, dissolve, embolize, or become organized into the vessel wall.
What is Virchow’s Triad?
Three key factors that contribute to thrombosis:
Endothelial injury (e.g., atherosclerosis, trauma, smoking).
Hypercoagulability (e.g., genetic disorders, pregnancy, cancer, oral contraceptives).
Stasis of blood flow (e.g., immobility, atrial fibrillation, varicose veins).
How does atheroma contribute to thrombosis?
Atheromatous plaques can rupture, exposing subendothelial collagen.
This triggers platelet adhesion, the coagulation cascade, and thrombus formation.
The thrombus may partially block the vessel (leading to ischemia) or fully occlude it (causing infarction).
What are common causes of thrombosis?
Endothelial damage → Atherosclerosis, smoking, hypertension, surgery.
Hypercoagulability → Genetic (Factor V Leiden, Protein C/S deficiency), cancer, pregnancy, oral contraceptives.
Blood stasis → Immobilization, atrial fibrillation, deep vein thrombosis (DVT).
What is an embolism?
A detached thrombus or other material that travels through the bloodstream and blocks a vessel
What are common types of emboli?
Thromboembolism (most common) → Dislodged blood clot (e.g., pulmonary embolism).
Fat embolism → From fractured long bones.
Air embolism → From diving or IV injections.
Amniotic fluid embolism → Rare complication of childbirth.
