Watchman LAA Closure Compared With Long-Term Warfarin Regarding Bleeding Outcomes

November 25, 2015—A comparison of the relative risk of major bleeding in left atrial appendage closure (LAAC) compared with long-term warfarin therapy was published online ahead of print by Matthew J. Price, MD, et al in the Journal of the American College of Cardiology (JACC): Cardiovascular Interventions.

The investigators conducted a pooled, patient-level analysis of two randomized clinical trials (PROTECT AF and PREVAIL) that studied LAAC using Boston Scientific’s Watchman device compared with long-term warfarin therapy in atrial fibrillation (AF). The analysis included 1,114 patients, and median follow-up was 3.1 years.

There was no difference in the overall rate of major bleeding in patients assigned to LAAC compared with extended warfarin therapy over 3 years of follow-up. However, LAAC treatment significantly reduced bleeding beyond the procedural period, particularly once adjunctive pharmacotherapy was discontinued. The favorable effect of LAAC on long-term bleeding should be considered when selecting a stroke prevention strategy for patients with nonvalvular AF, concluded the investigators.

As summarized in JACC: Cardiovascular Interventions, the overall rate of major bleeding from randomization to the end of follow-up was similar between treatment groups (3.5 vs 3.6 events per 100 patient-years; rate ratio [RR], 0.96; 95% confidence interval [CI], 0.66–1.40; P = .84). 

LAAC with the Watchman device significantly reduced bleeding > 7 days postrandomization (1.8 vs 3.6 events per 100 patient-years; RR, 0.49; 95% CI: 0.32–0.75; P = .001), with the difference emerging 6 months after randomization (1 vs 3.5 events per 100 patient-years; RR, 0.28; 95% CI, 0.16–0.49; P < .001), when patients assigned to LAAC were able to discontinue adjunctive oral anticoagulation and antiplatelet therapy. The reduction in bleeding with LAAC with the Watchman device was directionally consistent across all patient subgroups, reported the investigators in JACC: Cardiovascular Interventions.