Background Either dual antiplatelet therapy or oral anticoagulation in combination with aspirin represent recommended treatment regimens following left atrial appendage closure (LAAC). As the majority of patients receiving LAAC have high bleeding risk, less aggressive antithrombotic treatments are needed, such as single antiplatelet therapy.Objectives To compare both ischemic and bleeding outcomes in patients receiving single (SAPT) or dual antiplatelet therapy (DAPT) after successful LAAC.Methods Data on consecutive patients undergoing percutaneous LAAC between 2009 and 2023 were prospectively collected including one-year follow-up. A propensity score matching was performed among patients discharged under SAPT and DAPT. The primary endpoint was the one-year composite of cardiovascular death, stroke, systemic embolism or device related thrombosis (DRT). The secondary endpoints included major bleeding and DRT.Results Among 1033 patients discharged with antiplatelet therapy, 154 patients receiving SAPT were compared to 230 matched patients receiving DAPT. The primary endpoint was similar between the two study groups (SAPT 11.0% vs. DAPT 8.3%; Rate Ratio [RR]: 1.14; 95% Confidence Interval [CI]: 0.83-1.55; p=0.420). Consistently, we found no difference in terms of both major bleedings (SAPT 9.7% vs. DAPT 12.6%; Hazard Ratio: [HR]: 0.77; 95% CI: 0.43-1.39; p=0.387) and DRT (2.6% vs. 1.1%; RR:1.47; 95% CI: 0.89-2.43; p=0.130) between SAPT and DAPT groups.Conclusions In this propensity score analysis of a single-center LAAC cohort, both ischemic and bleeding outcomes did not differ at 1 year between patients discharged with SAPT or DAPT. These results have to be confirmed in an adequately powered randomized clinical trial.
