What are the results of the PROTECT AF and PREVAIL AF trials evaluating the WATCHMAN device?
The PROTECT AF trial found that the efficacy of LAA closure with the WATCHMAN device met the pre-specified criteria for non-inferiority to warfarin. However, the rate of adverse safety events in the intervention group was 4.4% with evidence of harmful periprocedural complications (pericardial effusion and procedure-related ischemic stroke). The PREVAIL AF trial found that at 60 months follow-up, the primary safety endpoint of stroke, systemic embolism, and cardiovascular/ unexplained death was not significantly different between the WATCHMAN device and warfarin-treated patients.