Additional Effects of Antiplatelet Therapy on Anticoagulant Agents in Patients With Bioprosthetic Valves and Atrial Fibrillation

Background: The additional effects of single-antiplatelet therapy (SAPT) on anticoagulant therapy are still unclear in patients with atrial fibrillation (AF) after bioprosthetic valve replacement. Methods and Results: We conducted a subanalysis of a multicenter, retrospective, observational registry of patients with biopros-thetic valves and AF in Japan. Patients administered anticoagulants alone comprised the ACA group (n=107), and patients given concomitant SAPT and anticoagulant therapy comprised the On SAPT group (n=82). The primary efficacy endpoint was the incidence of stroke/systemic embolism, and the primary safety endpoint was the incidence of major bleeding. The observation period was 46.3 +/- 24.6 months. The primary efficacy endpoint occurred in 12 patients, and the cumulative incidence of primary efficacy events was significantly higher in the ACA group compared with the On SAPT group (P=0.039). The primary safety endpoint occurred in 22 patients, and the cumulative incidence of primary safety events was similar between groups (P=0.66). No differences between the groups were observed for cardiac events. Conclusions: Additional SAPT on anticoagulant therapy in patients with bioprosthetic valves and AF was associated with a reduc-tion in stroke/systemic embolic events, although the cumulative incidence of bleeding was similar, regardless of additional SAPT. These findings suggest that additional SAPT on anticoagulant therapy may be safe and effective in real-world clinical settings.