Thrombosis & drugs Flashcards
What is Virchow’s triad?
Stasis
Vessel wall
Hypercoagulability
How does treatment of arterial vs venous thrombosis differ?
Arterial = anti-platelets Venous = anti-coagulants
What is thrombophilia?
Familial or acquired disorders of the haemostatic mechanism which are likely to predispose to thrombosis
What is the treatment of hereditary thrombophilia?
Avoid risk
Short term prophylaxis
Short term anticoagulation
Long term anticoagulation
What are the features of anti-phospholipid syndrome?
Recurrent thromboses
Recurrent fetal loss
Mild thrombocytopenia
How do anti-phospholipid antibodies cause thromboses cause thrombosis?
Conformational change in B2 glycoprotein 1 - leads to activation od both primary and secondary haemostasis and vessel wall abnormalitis
What are anti-phospholipid antibodies also known as?
Lupus anticoagulants
What conditions are associated with anti-phospholipid antibodies?
Autoimmune disorders Lymphoproliferative disorders Viral infections Drugs Primary
How is anti-phospholipid syndrome treated?
Aspirin & Warfarin
How do platelets bind to subendothelial collagen?
Via Glycoprotein 1b & VWF
How do platelets attach to each other?
GPIIbIIa & fibrinogen
What is the mechanism of action of aspirin?
Inhibits cyclo-oxygenase which is necessary toproduce Thromboxane A2 (a platelet agonist released from granules on activation)
Side effects of aspirin
Bleeding
GI ulceration
Bronchospasm
What type of drugs are clopidogrel & prasugrel?
ADP receptor antagonists
What is the mechanism of action of dipyridamole?
Phosphodiesterase inhibitor - reduces production of cAMP which is a ‘second messenger’ in platelet activation
