Aspirin is used for secondary prevention of ischemic hea disease because it:-
Aggregatory substances: TXA2 ADP Inhibits aggregation: PGI2. Aspirin is Irreversible inhibitor of COX - thus preventing TXA2 formation & aggregation of PLATELETS.
Inhibits TXA2 synthesis by platelets
Inhibit prostacyclin synthesis
Inhibits release of EDRF
Inhibit synthesis of endothelins
Histamine, 5-HT and PGs