Abstract

BACKGROUND: This propensity-score matched study investigated clinical outcomes associated with left atrial appendage occlusion (LAAO) versus direct oral anticoagulation (DOAC) in patients with AF and prior ischemic stroke. METHODS: AF patients enrolled in the Amulet Observational Study with a history of ischemic stroke and successful LAAO (n = 299) were compared with a propensity-score matched cohort of incident AF patients with prior ischemic stroke and treated by DOAC (n = 301). The control cohort was identified through the Danish National Patient Registries. Propensity score matching was based on covariates of the CHA2DS2-VASc and HAS-BLED scores, with a 1:2 ratio and using Greedy 5:1 digit matching with replacement. The analysis included 2-years follow-up, with a primary composite outcome of ischemic stroke, major bleeding (BARC ≥ 3) or all-cause mortality. RESULTS: Mean (SD) CHA2DS2-VASc scores were 5.26 (1.42) and 5.40 (1.31) and HAS-BLED scores were 3.95 (0.91) and 4.03 (0.96), for the LAAO and DOAC group, respectively. Total number of primary composite outcome events were 61 (12.4 events/100 patient-years) and 117 (26.9 events/100 patient-years) in the LAAO and DOAC group, respectively. Risk of the primary composite outcome was significantly lower in the LAAO group, hazard rate ratio [HR] 0.48 (95% CI: 0.35-0.65). Ischemic stroke risk was comparable, HR 0.71 (95% CI: 0.34-1.45), while risk of major bleeding, HR 0.41 (95% CI: 0.25-0.67), and all-cause mortality, HR 0.48 (95% CI: 0.32-0.71), were significantly lower with LAAO. Cardiovascular mortality did not differ statistically between the LAAO and DOAC group, HR 0.75 (95% CI: 0.39-1.42). Results were consistent across sensitivity analyses. CONCLUSION: This study indicated significantly lower risk of the composite outcome of stroke, major bleeding and all-cause mortality with LAAO therapy compared to DOAC, in patients with AF and prior stroke. The stroke prevention effectiveness appeared similar, with a significantly lower risk of major bleeding events with LAAO. The suggested clinical benefit of LAAO over DOAC require confirmation in the ongoing randomized OCCLUSION-AF trial.