What is the purpose of antiplatelet medications after a myocardial infarction (MI)?

• A. They block platelet aggregation and improve survival in patients after MI.
• B. They raise platelet activity to prevent bleeding.
• C. They lower LDL cholesterol directly.
• D. They increase heart rate.

Answer: (A)

After a myocardial infarction, preventing another clot is essential. Antiplatelet medications block platelet aggregation, which reduces the risk of recurrent thrombosis at the site of plaque rupture and improves survival. Aspirin inhibits thromboxane A2 production in platelets, lowering their activation, while other agents like P2Y12 inhibitors prevent ADP-mediated platelet aggregation. Together, they form a cornerstone of post-MI therapy. They do not raise platelet activity, they do not directly lower LDL cholesterol, and they do not increase heart rate.