02/23e Thrombosis II Flashcards
What is thrombosis?
Formation of a blood clot in an artery or vein of a living person
Arterial thrombosis denies oxygen and nutrition to an area of the body
Venous thrombosis blocks return of deoxygenated blood to the heart
What is mural thrombosis?
Extension of a thrombus into a vessel without blocking it completely
What is occlusive thrombosis?
Complete blockage of a blood vessel
What is propagative thrombosis?
Extension of a thrombus along a blood vessel
What is major possible complication of venous thrombosis?
Pulmonary embolism
How can you differentiate a post-mortem clot from a pre-mortem thrombus or embolus?
A thrombus is layered, friable, adheres to the vessel wall
A post-mortem clot is soft, jelly-like, and comes away easily from the vessel wall
What is Virchow’s triad?
Details major causes of thrombosis
Includes stasis, vascular injury, and hypercoagulability
How does stasis lead to thrombosis?
Low flow and turbulence can damage endothelial cells and cause buildup of tissue factor
Blood return to the heart from the extremities is decreased
How does vascular injury lead to thrombosis?
Initiates clotting cascade, which may propagate inappropriately
What can cause hypercoagulability?
Gene defects APC resistance/factor V Leiden Prothrombin mutation Anti-phospholipid antibodies Inflammation Impaired fibrinolysis Lifestyle and environment
Describe the intimate connection between thrombosis and atherosclerotic plaque development
Thrombosis can occur on atherosclerotic plaques, especially if they rupture
Formation of a thrombus (deposition of fibrin, activation of platelets) intravascularly is associated with development of atherosclerotic lesions
Sites of vascular injury and turbulence are also sites of plaque development
