Abstract 10131: Real World Comparative Outcomes From Left Atrial Appendage Occlusion versus Anticoagulation Among Females and Males

Abstract

Introduction: Clinical decision-making around AF-related stroke risk management is complicated by the widely available and safe direct acting oral anticoagulants (AC) and uncertain long term risks of left atrial appendage occlusion (LAAO) in patients who are older and more female than clinical trial participants. Hypothesis: Among matched sex-stratified Medicare beneficiaries with AF, there is no difference in risk of mortality, stroke, and bleeding associated with LAAO versus AC alone. Methods: Medicare beneficiaries with AF and CHA2DS2VASc of 2 (males) or 3 (females) (2015-2019) were divided into those who underwent LAAO or received AC only. LAAO and AC patients were propensity score matched 1:1 within sex subgroups based on available characteristics. A Cox proportional hazards model was used to model the survival time from the LAAO implant date to evaluate the comparative risks of mortality, stroke/thromboembolism, and any bleeding events based on ICD-10 codes. Results: Matching sex-stratified AC and LAAO patients was successful (SMD < 10% on all variables). Average follow-up was 1 year. Among females (n=4,085; mean 76 years, CHA2DS2VASc 5.1), LAAO was associated with reduced risk of mortality and stroke/thromboembolism (HR 0.51 95% CI 0.45-0.58; HR 0.66 95% CI 0.56-0.77, p<0.0001) compared with AC; similar findings were observed among males (n=5,378; mean 75.3 years, CHA 2 DS 2 VASc 4.1) regarding mortality and stroke/ thromboembolism (HR 0.54 95% CI 0.49-0.60; HR 0.65 95% CI 0.55-0.76, p<0.0001). Comparative bleeding risk varied over time with LAAO associated with greater risk early then lesser risk (females HR 1.03 95% CI 0.92-1.16; males HR 1.05 95% CI 0.95-1.17). (Figure) Conclusion: Within sex subgroups during an average of 1 year follow up, LAAO was associated with a reduced risk of mortality and stroke/thromboembolism when compared with AC alone among Medicare beneficiaries with AF. There was no difference in the risk of bleeding between LAAO and AC groups.