CHAMPION-AF: WATCHMAN FLX non-inferieur aan NOAC's en superieur in bloedingsreductie bij atriumfibrilleren

Background: Left atrial appendage (LAA) closure is an alternative to oral anticoagulation for stroke prevention in atrial fibrillation. Whether LAA closure with the WATCHMAN FLX device is noninferior to direct oral anticoagulants (NOACs) as a first-line therapy is unknown. Methods: In this multicenter, randomized, open-label trial at 141 sites, we assigned 3,000 patients with non-valvular atrial fibrillation and CHA2DS2-VASc score of 2 or more to WATCHMAN FLX implantation (1,499 patients) or NOAC therapy (1,501 patients). The primary efficacy endpoint was a composite of ischemic stroke, hemorrhagic stroke, cardiovascular death, and systemic embolism at 36 months. The primary safety endpoint was non-procedural major and clinically relevant non-major bleeding. Results: Procedural success was 99%. At 36 months, the primary efficacy endpoint occurred in 5.7% of the device group versus 4.8% of the NOAC group (noninferiority met; P<0.001). The primary safety endpoint occurred in 10.9% of the device group versus 19.0% of the NOAC group, a 45% relative reduction in non-procedural bleeding (P<0.001 for superiority). The composite secondary endpoint of cardiovascular death, stroke, systemic embolism, and non-procedural major bleeding occurred in 15.1% versus 21.8% (P<0.001 for superiority). Conclusions: Among patients with non-valvular atrial fibrillation, WATCHMAN FLX was noninferior to NOACs for the prevention of stroke and systemic embolism and superior in reducing non-procedural bleeding.