Abstract 9599: Impact of Sex on Outcomes After WATCHMAN FLX Implantation

Introduction: Female sex is an established, non-modifiable risk factor for adverse outcomes in atrial fibrillation (AF) patients. Left atrial appendage occlusion (LAAO) has been shown to be generally safe and effective for stroke prevention in patients with AF. Data on sex-based outcomes with WATCHMAN FLX is lacking. Methods: WATCHMAN FLX patients from the National Cardiovascular Data Registry LAAO Registry between August 5th 2020 and March 31st 2021 were analyzed. Results: Women at baseline had a higher average CHA 2 DS 2 -VASc score, were more likely to have a history of transient ischemic attack, thromboembolic event, peripheral or carotid artery disease, fall risk, and chronic lung disease than men. Conversely, history of congestive heart failure, left ventricular dysfunction, hypertension, diabetes, vascular disease, abnormal renal function, cardiomyopathy, non-paroxysmal atrial fibrillation, myocardial infarction, prior cardiac interventions, alcohol use, antiplatelet medication use and non-steroidal anti-inflammatory drug use were all reduced in women compared to men. The early safety endpoint was similar between women and men ( Table ). At 45 days, unadjusted rates of major adverse events were higher in women than men mainly due to differences in major bleeding and pericardial effusion ( Table ). The risk of death was lower in women than men at 45 days. Rates of stroke, major vascular complications, systemic thromboembolism, myocardial infarction, and device-related thrombus were not significantly different between sexes. Adjusted outcomes will be available at the time of the presentation. Conclusions: In this national unselected cohort, there are significant sex-based differences in baseline characteristics and comorbidity burden. Women experienced more major adverse events after LAAO than men. Additional research to determine the underlying mechanisms of the increased risk in women and strategies for closing the gap between sexes are needed.