Is the aspirin prescription being used to treat or prevent coronary artery disease (CAD)?

Yes, aspirin is definitively indicated for CAD treatment and prevention.

Aspirin 75-100 mg daily is recommended lifelong for patients with established coronary artery disease (CAD), including those with prior myocardial infarction, revascularization (PCI or CABG), or imaging-confirmed significant obstructive CAD 1.

Clinical Context Determines Aspirin Use

The 2024 ESC Guidelines provide clear, evidence-based recommendations for aspirin in CAD (chronic coronary syndrome):

Established CAD with Prior Events (Class I, Level A)

• Prior MI or PCI: Aspirin 75-100 mg daily lifelong after initial DAPT period 1
• Post-CABG: Aspirin 75-100 mg daily lifelong 1
• This represents the strongest level of evidence and recommendation

Established CAD without Prior Events (Class I, Level B)

• Imaging-confirmed significant obstructive CAD: Even without prior MI or revascularization, aspirin 75-100 mg daily is recommended lifelong 1
• This recommendation was upgraded from Class IIb/Level C in 2019 to Class I/Level B in 2024, reflecting stronger evidence

Post-PCI Management

• Initial DAPT (aspirin + clopidogrel) for up to 6 months is standard 1
• After DAPT completion, aspirin monotherapy continues lifelong 1

Alternative to Aspirin

Clopidogrel 75 mg daily is an equally effective alternative (Class I, Level A) for patients with:

• Aspirin intolerance 1
• Prior MI or remote PCI who cannot take aspirin 1

Recent evidence suggests clopidogrel may provide comparable or superior cardiovascular protection with potentially lower bleeding risk in selected populations 2.

Critical Distinction: Secondary vs. Primary Prevention

This is NOT for primary prevention. Recent trials (ARRIVE, ASCEND, ASPREE) and current guidelines have significantly restricted aspirin use in patients without established CAD due to bleeding risks outweighing modest cardiovascular benefits 3, 4, 5. The evidence and recommendations above apply specifically to secondary prevention in patients with established CAD.

Important Caveats

Bleeding Risk Considerations

• Aspirin increases risk of gastrointestinal bleeding and intracranial hemorrhage 6
• Higher risk in patients ≥60 years, history of ulcers, concurrent anticoagulation, or ≥3 alcoholic drinks daily 6
• Proton pump inhibitor recommended for patients at increased GI bleeding risk 1

Special Populations

• Pregnancy: Avoid in last trimester unless specifically directed by physician 6
• Reye's syndrome risk: Contraindicated in children/teenagers with viral illnesses 6
• Oral anticoagulation: In patients requiring OAC (e.g., atrial fibrillation), aspirin is typically discontinued after brief initial period (≤1 week post-PCI), continuing with OAC + clopidogrel, then OAC alone 1, 7

Bottom Line

If the patient has established CAD (documented MI, prior revascularization, or imaging-proven significant obstructive disease), aspirin is definitively indicated for secondary prevention unless contraindicated or replaced by clopidogrel for intolerance. The 2024 ESC guidelines provide the highest level of recommendation (Class I) with strong evidence (Level A-B) supporting lifelong aspirin therapy in this population 1.