Evolution of Stroke Prevention in Nonvalvular Atrial Fibrillation Patients ∗

The PREVAIL (Watchman LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy) trial is the latest in the series of studies evaluating left atrial appendage (LAA) occlusion with the Watchman device (Boston Scientific, Natick, Massachusetts) as an alternative to warfarin therapy for the prevention of stroke in patients with nonvalvular atrial fibrillation (NVAF). The PREVAIL trial was initially designed as a follow-up study to PROTECT AF (Watchman Left Atrial Appendage Closure Technology for Embolic Protection in Patients With Atrial Fibrillation), which demonstrated noninferiority to warfarin in preventing stroke (1). However, the U.S. Food and Drug Administration (FDA) raised concerns regarding acute safety events and the selection of low stroke risk patients (CHADS2 score of 1). In addition, many patients in PROTECT AF were treated with chronic clopidogrel and/or remained on warfarin >45 days after device implantation. Thus, at the request of the FDA, the PREVAIL study was designed to address the limitations of PROTECT AF and to assess the safety and efficacy of LAA occlusion for stroke prevention compared with long-term warfarin therapy in patients with NVAF.
Source: Journal of the American College of Cardiology: Cardiovascular Imaging - Category: Radiology Source Type: research