What is the main mechanism of action of aspirin in preventing myocardial infarction
Question : What is the main mechanism of action of aspirin in preventing myocardial infarction?
A. Inhibiting platelet aggregation
B. Lowering blood pressure
C. Reducing blood lipid levels
D. Improving myocardial oxygen supply
Answer: A
Explanation: Aspirin irreversibly inhibits cyclooxygenase (COX), thereby reducing the synthesis of thromboxane A2 (TXA2), inhibiting platelet aggregation, and preventing the formation of arterial thromboses, which is the core mechanism for preventing myocardial infarction. Aspirin has no obvious blood pressure-lowering or lipid-lowering effects; improving myocardial oxygen supply is the mechanism of nitrates. Therefore, the correct answer is A.
