Aspirin Alone Versus Dual Antiplatelet Therapy After Transcatheter Aortic Valve Implantation: A Systematic Review and Patient-Level Meta-Analysis

Background In patients undergoing transcatheter aortic valve implantation without an indication for oral anticoagulation, it is unclear whether single or dual antiplatelet therapy (DAPT) is necessary to minimize both the bleeding and thromboembolic risk. In this patient-level meta-analysis, we further investigate the effect of aspirin alone compared with DAPT for preventing both thromboembolic and bleeding events after transcatheter aortic valve implantation. Methods and Results We conducted a systematic review of all available randomized controlled trials comparing aspirin with DAPT. In total, 1086 patients were included across 4 eligible trials. The primary outcomes were the composite of all-cause mortality, major or life-threatening bleeding, stroke or myocardial infarction (first composite outcome), and the same composite excluding bleeding (second composite outcome), both tested at 30 days and 3 months. The first composite outcome occurred significantly less in the aspirin-alone group at 30 days (10.3% versus 14.7%, odds ratio [OR], 0.67; 95% CI, 0.46-0.97, P=0.034) and 3 months (11.0% versus 16.5%, hazard ratio [HR], 0.66; 95% CI, 0.47-0.94, P=0.02), compared with the DAPT group. The second composite outcome occurred in 5.5% and 6.6% at 30 days (OR, 0.83; 95% CI, 0.50-1.38, P=0.47) and in 6.9% and 8.5% at 3 months in the aspirin-alone group compared with the DAPT group (HR, 0.82; 95% CI, 0.52-1.29, P=0.39), respectively. Conclusions In patients without an indication for oral anticoagulation undergoing transcatheter aortic valve implantation, aspirin alone significantly reduced the composite of thromboembolic and bleeding events, and does not increase the composite of thromboembolic events after transcatheter aortic valve implantation, compared with DAPT.