Dual antiplatelet therapy versus aspirin alone after coronary artery bypass grafting: a systematic review and meta-analysis

To determine whether dual antiplatelet therapy improves survival and major ischemic outcomes, and whether it increases major bleeding, compared with aspirin alone after coronary artery bypass grafting. PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched from inception to March 2026 for randomized controlled trials comparing aspirin plus a platelet adenosine diphosphate receptor inhibitor with aspirin alone after coronary artery bypass grafting. The primary outcome was all-cause mortality. Secondary outcomes were major adverse cardiovascular events, myocardial infarction, stroke, and major bleeding. Risk ratios were pooled with random-effects models. Nine randomized trials involving 3,516 patients were included. Eight trials involving 3,496 patients reported all-cause mortality. Dual antiplatelet therapy was not associated with a significant reduction in all-cause mortality (risk ratio 0.77, 95% confidence interval 0.34-1.75), myocardial infarction (risk ratio 0.92, 95% confidence interval 0.56-1.50), stroke (risk ratio 0.68, 95% confidence interval 0.33-1.43), or major adverse cardiovascular events (four trials, 3,054 patients; risk ratio 0.69, 95% confidence interval 0.41-1.16). Major bleeding was increased in the primary analysis (risk ratio 2.28, 95% confidence interval 1.48-3.52), but this association was attenuated after exclusion of the largest contemporary trial. In randomized evidence, dual antiplatelet therapy did not clearly reduce mortality or major ischemic events after coronary artery bypass grafting compared with aspirin alone. Routine, unselected use is not supported, and individualized postoperative antiplatelet decisions remain warranted.