Outcomes Associated With Left Atrial Appendage Occlusion Via Implanted Device in Atrial Fibrillation

Objective: To compare outcomes after left atrial appendage occlusion (LAAO) via implanted device vs no LAAO in a matched cohort of patients with atrial fi brillation (AF). Methods: This longitudinal retrospective cohort study was based on the national database covering hospital care for the entire French population. Adults ( > 18 years of age) who had been hospitalized with AF (January 1, 2015, to January 1, 2020) who underwent LAAO were identi fi ed. Propensity score matching was used to control for potential confounders of the treatment -outcome relationship. The primary outcome was a composite of ischemic stroke, major bleeding, or all -cause death during follow-up. Results: After propensity score matching, 1216 patients with AF who were treated with LAAO were matched with 1216 controls (patients AF who were not treated with LAAO). Mean follow-up was 14.5 months (median, 13 months; IQR, 7-21 months). Patients with LAAO had a lower risk of the composite outcome (HR, 0.48; 95% CI, 0.42 to 0.55). Total events (309 for LAAO vs 640 for controls) and event rates (23.3% vs 44.0%/year, respectively) were lower for LAAO, driven primarily by a decreased risk of all -cause death (HR, 0.39; 95% CI, 0.33 to 0.46; P < .0001), whereas ischemic stroke risk was higher (HR, 1.75; 95% CI, 1.17 to 2.64). Signi fi cant interactions were observed in subgroups with a history of ischemic stroke ( P < .001) and of bleeding ( P = .002). Conclusion: Among AF patients at high bleeding risk, our nationwide study highlights a high risk of clinical events during follow-up. LAAO appeared less effective than no LAAO in preventing stroke but more effective in preventing death. Left atrial appendage occlusion is particularly effective in patients with previous ischemic stroke or any episode of bleeding.