PREVAIL trial of Watchman LAAC (Boston Scientific) shows some benefits for AF patients

New results on the PREVAIL trial, which randomized 407 patients with nonvalvular Atrial Fibrillation to either LAA closure with the Watchman device, from Boston Scientific or warfarin, indicates the study has met 2 of its 3 primary end points. Data shows that the device was implanted more successfully in the trial (95.1%) than in 2 prior Watchman studies: PROTECT AF (90.9%) and the Continued Access Protocol (CAP) registry (94.3%). The first primary endpoint (acute occurrence of death, ischemic stroke, systemic embolism, and complications requiring major cardiovascular or endovascular intervention) was met with only 6 total events (2.2%) in the device group through 7 days.

Compared with PROTECT AF and the CAP registry, PREVAIL showed decreased composite vascular complications and perforations requiring surgical repair. There was also a decrease in procedural stroke rates. LAA closure did not show better outcomes in the second primary outcome (composite of stroke, systemic embolism, and cardiovascular / unexplained death at 18 months). However, Watchman did show a benefit with regard to the third primary endpoint (ischemic stroke or systemic embolism after 7 days and up to 18 months). Data was released prior to the American College of Cardiology Scientific Session.