Abstract Body (Do not enter title and authors here): Hypothesis and Purpose: Guidelines recommend continuation of anticoagulation following atrial fibrillation (AF) ablation in patients at high risk for stroke. Left atrial appendage closure (LAAC), a mechanical alternative to stroke prevention, has not been studied after AF ablation.
Study Design and Methods: OPTION is a multicenter, randomized, FDA pivotal controlled trial (NCT03795298).
Population Studied: Patients planned for catheter ablation of AF and elevated CHA₂DS₂-VASc (male ≥2, female ≥3) were eligible if the ablation occurred 90-180 days prior to or within 10 days of randomization.
Intervention: Patients were randomized 1:1 to ablation+LAAC (WATCHMAN FLX) vs ablation+OAC stratified by site and ablation timing (sequential/concomitant to LAAC).
Power Calculation: To show noninferiority of LAAC vs OAC for primary efficacy and superiority for primary safety, 1360 patients provides 86% power.
Primary End Points: The primary safety endpoint is 36-month (M) non-procedural bleeding based on International Society on Thrombosis and Haemostasis [ISTH] major bleeding or clinically relevant non-major bleeding definitions. The primary efficacy endpoint is 36M all-cause death, stroke, or systemic embolism.
Secondary End Points: The secondary endpoint is 36M ISTH major bleeding. Additional endpoints include primary endpoint components, peridevice leaks and, device-related thrombosis (3M,12 M) and quality of life (12M, 36 M).
Outcomes: Between 20May19 and 16Jul21, 1600 patients were randomized to catheter ablation+LAAC (n=803) or ablation+OAC (n=797) at 114 sites. Overall, patients are ~70 years, 34% women, mean CHA₂DS₂-VASc score is 3.5, and mean HAS-BLED is 1.2. Patients randomized to anticoagulation mostly (95.0%) received a non-warfarin oral anticoagulant. LAAC was performed either concomitant with (40.8%) or sequentially after (59.2%) AF ablation. There were significantly fewer primary safety events with LAAC than anticoagulation (8.5% vs 18.1%; Psuperiority <0.0001). Primary efficacy event rates were comparable between LAAC and anticoagulation (5.3% vs 5.8%; Pnoninferiority <0.0001). Major bleeding rates were comparable between LAAC and anticoagulation (3.9% vs 5.0%; Pnoninferiority <0.0001).
Conclusions: Among moderate-high risk patients undergoing AF ablation, LAAC resulted in significantly less non-procedural bleeding than oral anticoagulation, while preserving similarly low rates of stroke, systemic embolism or death.