BackgroundLimited data are available describing left atrial appendage closure (LAAC) and age-related outcomes in Asians.ObjectivesThis study summarizes the initial experience with LAAC in Japan and determines age-related clinical outcomes in patients with nonvalvular atrial fibrillation undergoing percutaneous LAAC.MethodsIn an ongoing, prospective, investigator-initiated, multicenter, observational registry of patients undergoing LAAC in Japan, we analyzed short-term clinical outcomes in patients with nonvalvular atrial fibrillation who underwent LAAC. Patients were classified into younger, middle-aged, and elderly groups (≤70, 70 to 80, and >80 years of age, respectively) to determine age-related outcomes.ResultsPatients (n = 548; mean age, 76.4 ± 8.1 years; male, 70.3%) who underwent LAAC at 19 Japanese centers between September 2019 and June 2021 were enrolled in the study, including 104, 271, and 173 patients in the younger, middle-aged, and elderly groups, respectively. Participants had a high-risk of bleeding and thromboembolism with a mean CHADS2score of 3.1 ± 1.3, a mean CHA2DS2-VASc score of 4.7 ± 1.5, and a mean HAS-BLED score of 3.2 ± 1.0. Device success rates were 96.5% and anticoagulants discontinuation at the 45-day follow-up was achieved in 89.9%. In-hospital outcomes were not significantly different, but major bleeding events during the 45-day follow-up were significantly higher in the elderly group compared to the other groups (younger vs middle-aged vs elderly, 1.0% vs 3.7% vs 6.9%, respectively;P= 0.047) despite the same postoperative drug regimens.ConclusionsThe initial Japanese experience with LAAC demonstrated safety and efficacy; however, perioperative bleeding events were more common in the elderly and postoperative drug regimens must be tailored (OCEAN-LAAC [Optimized Catheter Valvular Intervention–Left Atrial Appendage Closure] registry;UMIN000038498)