Sex Differences in the Clinical Outcomes After Left Atrial Appendage Closure: A Systematic Review and Meta-Analysis

Introduction: Left atrial appendage occlusion (LAAO) has emerged as a reasonable alternative to oral anticoagulation in a selective group of patients with atrial fibrillation (AF). While women are known to have higher risk of AF-related stroke, the impact of sex differences on the clinical outcomes of LAAO has not been well-studied. Objective: We sought to perform a meta-analysis evaluating sex differences on the outcomes of patients undergoing LAAO. Methods: We searched PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases (from inception to October 2021) for studies evaluating the impact of sex difference on LAAO procedural outcomes. We used a random-effects model to calculate risk ratio (RR) with 95% confidence intervals (CI). In-hospital all-cause mortality and ischemic stroke were the primary endpoints. In-hospital pericardial effusion/cardiac tamponade, major bleeding, technical success, device-related thrombus, and hospital length of stay were secondary outcomes. Results: A total of 5 studies with 54,754 patients were included, of whom 22,461 (41%) were females. Female sex was associated with higher rates of in-hospital all-cause mortality (RR 2.18; 95% CI 1.46–3.26; P = 0.0001) and in-hospital ischemic stroke (RR 1.67; 95% CI 1.06–2.61; P = 0.03) when compared with males. Females had higher rates of in-hospital major bleeding (RR 1.93; 95% CI 1.40–2.67; P < 0.0001) and hospital length of stay >1 day (RR 1.38; 95% CI 1.33–1.45; P < 0.00001). There were no differences between females and males in terms of technical success (RR 1.00; 95% CI 1.00–1.00; P = 1.00) and device-related thrombus and (RR 0.94, 95% CI 0.31–2.82; P = 0.91). Conclusion: Women are more likely to experience worse periprocedural outcomes with longer hospital stay after LAA closure. Further efforts are needed to increase the participation of women in clinical studies and to assess these differences to properly address the discrepancy in outcomes between men and women.