Arterial thrombosis and antiplatelet drugs Flashcards
Give examples of arterial thrombotic events
MI
stroke
peripheral - ischaemic leg
why do you get atherosclerosis in arteries and not veins
arteries have a high pressure system
is atherosclerosis the same as arterial thrombosis
NO
arterial thrombosis occurs as a result of ruptured atherosclerotic plaques
how do atherosclerotic plaques form
endothelial damage causes recruitment of foamy macrophages filled with cholesterol which are deposited to form plaques
what are consequences of a stable atherosclerotic plaque
vessel lumen is reduced so there is reduced blood flow
stable angina
intermittent claudication
what are consequences of unstable atherosclerotic plaque
rupture causes formation of arterial platelet rich thrombus which occludes the vessel leading to organ ischaemia and infarction
unstable angina, MI
stroke
risk factors for arterial thrombosis
age obesity high cholesterol smoker DM HTN
what can be done to prevent arterial thrombosis
lifestyle modification stop smoking, lose weight treat HTN and DM lower cholesterol antiplatelet drugs
How are platelets formed
budding off of megakaryocytes found in the bone marrow
in platelet plug formation, what happens during platelet adhesion
platelets bind to subendothelial collagen via VWF and glycoprotein 1b
in platelet plug formation, what happens during platelet aggregation
platelets adhere to eachother via GPIIb/IIIa and fibrinogen
in platelet plug formation, what happens during platelet activation
Platelets alter their shape to expose more phospholipid to increase SA for coagulation activation and fibrin formation
Release of Thrombin, TXA2, ADP to help platelets stick together
how does aspirin work
inhibits COX1 enzyme which reduces formation of TXA2
reduced platelet aggregation
side effects of aspirin
bleeding
reduced prostaglandin synthesis –> PUD
bronchospasm
how do clopidogrel and prasugrel work
ADP receptor antagonists
reduced platelet aggregation
