Minimally Invasive Epicardial Surgical Left Atrial Appendage Exclusion for Atrial Fibrillation Patients at High Risk of Stroke and of Bleeding.

BACKGROUND: Atrial fibrillation (AF) patients at high risk for stroke and also at high risk for bleeding may be unsuitable for either oral anticoagulation or endocardial left atrial appendage (LAA) occlusion. However, minimally invasive, epicardial LAA exclusion (LAAE) may be an option.

OBJECTIVE: To evaluate outcomes of LAAE in high-risk AF patients not on oral anticoagulation.

METHODS: A retrospective analysis of Medicare claims data was conducted to evaluate thromboembolic events in AF patients who underwent LAAE compared to a 1:4 propensity score-matched group of patients who did not receive LAAE (control). Neither group was on any oral anticoagulation at baseline or follow-up. Fine-Gray models estimated hazard ratios and evaluated between-group differences; bootstrapping was applied to generate 95%-confidence intervals (CIs).

RESULTS: The LAAE group (N=243) was 61% male with a mean age of 75 years; AF was non-paroxysmal in 70% (mean CHA2 DS2 -VASc was 5.4 and mean HAS-BLED was 4.2); the matched control group (N=972) had statistically similar characteristics. One-year adjusted estimates of thromboembolic events were 7.3% (95% CI 4.3-11.1%) in LAAE and 12.1% (95% CI 9.5-14.8%) in the control group. Absolute risk reduction was 4.8% (95% CI 0.6-8.9%, P=0.028). The adjusted hazard ratio for thromboembolic events for LAAE versus non-LAAE was 0.672 (95% CI 0.394-1.146).

CONCLUSIONS: In AF patients not taking oral anticoagulation, at high risk of stroke and of bleeding, minimally invasive, thoracoscopic, epicardial LAAE was associated with a lower rate of thromboembolic events.