Indefinite Low‑Dose Aspirin Therapy After Coronary Artery Bypass Grafting (CABG)

Guideline Recommendations

The American College of Cardiology/American Heart Association (ACC/AHA) recommends lifelong aspirin therapy after any coronary revascularization, including CABG (Class I, Level A evidence). 1, 2, 3
The 2011 ACC/AHA/Society for Cardiovascular Angiography and Interventions (SCAI) PCI guideline states that indefinite aspirin use after PCI also applies to post‑CABG patients (Class I). 2, 3
The 2014 AHA/ACC guideline for non‑ST‑segment‑elevation acute coronary syndromes (NSTE‑ACS) reinforces indefinite aspirin at a maintenance dose of 81 mg daily (Class I, Level A). 1, 4

A low‑dose regimen of 81 mg aspirin daily is preferred over higher doses for secondary prevention (Class IIa, Level B). 4, 2, 5
Evidence shows that 81 mg provides comparable cardiovascular protection to 162–325 mg while substantially reducing bleeding risk (Level B). 4, 6, 5

There is no upper age limit for continuing aspirin in patients with established coronary artery disease who have undergone revascularization (Class I, Level A). 1, 2
Aspirin should not be discontinued solely on the basis of advanced age. 1, 2

Aspirin should be stopped only if the patient experiences active bleeding or a documented contraindication such as intracranial hemorrhage or a severe bleeding disorder (Class I, Level A). 1, 5
Discontinuation is also warranted when the documented risk of major bleeding clearly outweighs the anticipated cardiovascular benefit (Class IIa, Level B). 4, 5, 7

Higher aspirin doses should be avoided without a specific indication; the 81 mg dose offers the optimal benefit‑to‑risk ratio for long‑term secondary prevention. 4, 6, 5
Routine dual antiplatelet therapy (DAPT) is not recommended indefinitely after CABG; aspirin monotherapy suffices unless the patient has a recent acute coronary syndrome or PCI with stent placement (Class I, Level A). 7
Patients should be monitored for gastrointestinal symptoms; proton‑pump inhibitor co‑therapy is advisable for those with ulcer history, concurrent NSAID use, or other GI bleeding risk factors (Class IIa, Level B). 2, 5

Long‑term aspirin use improves saphenous vein graft patency after CABG, reducing the risk of graft occlusion (Class I, Level A). 7