Long-Term Aspirin Therapy After Myocardial Infarction
Guideline Recommendations
- The European Society of Cardiology recommends antiplatelet therapy with low-dose aspirin (75-100 mg daily) for all patients with prior MI, as a Class I, Level A recommendation 1, 2
- The American College of Cardiology/American Heart Association guidelines recommend aspirin be continued indefinitely after MI, with evidence supporting benefit for at least 2-3 years and extrapolated benefit beyond that timeframe 4, 5
Optimal Dosing
- The maintenance dose of aspirin should be 75-100 mg daily, providing equivalent efficacy to higher doses while minimizing bleeding complications 1, 2, 6
- After the initial post-MI period, the aspirin dose should be reduced to 75-100 mg daily 1, 2
Evidence Supporting Indefinite Continuation
- Aspirin reduces serious vascular events by approximately 25% in patients with prior MI, translating to 36 fewer events per 1000 patients treated for 2 years 6
- Aspirin 75 mg daily reduced myocardial infarction and sudden death by 34% after median follow-up of 50 months in chronic stable angina patients 6
Special Considerations
- If the patient has no indication for oral anticoagulation and tolerated aspirin without bleeding complications, continue aspirin 75-100 mg daily as monotherapy 1, 2
- Dual antiplatelet therapy (aspirin plus P2Y12 inhibitor) is typically discontinued after 12 months unless the patient has high ischemic risk features 1, 2
Gastrointestinal Protection
- Proton pump inhibitor co-therapy should be considered in patients with history of gastrointestinal bleeding or multiple bleeding risk factors, as a Class I, Level B recommendation 1, 2