Mechanism of action of Aspirin in MI is :

Ans is 'a' Thromboxane A2 synthesis inhibition (Ref Goodman Gilman, 10/e, p. 1534; KDT 5/e p. 572).Aspirin is used in MI because of its antiplatelet action.Antiplatelet action of aspirin: Aspirin blocks the production of thromboxane A2 by inactivating the enzyme cyclooxygenase. Cyclooxygenase is an enzyme that produces cyclic endoperoxide precursor of thromboxane A2.