Abstract 14157: Racial Differences in Outcomes of Ischemic Stroke and Mortality With Left Atrial Appendage Closure With Watchman Device in Medicare Population

Introduction: Left atrial appendage closure by Watchman implantation is a novel non-pharmacological alternative for stroke prevention in non-valvular atrial fibrillation (AF) patients who are deemed unable to take long term anticoagulation. Blacks and Hispanics were under-represented in the clinical trials for Watchman device and therefore more outcome data is needed in these populations. Hypothesis: We sought to study racial differences in outcomes of mortality and ischemic stroke in Medicare beneficiaries who received a Watchman device Methods: Medicare claims were used to identify 13,598 patients with AF who underwent Watchman implantation during January 2015 to November 2017. Patient demographics including race and comorbid conditions were identified based on the hospital discharge record. Death and readmission rate for ischemic strokes and transient ischemic attacks (TIA’s) were assessed. Primary readmission diagnoses were classified using the AHRQ Clinical Classification Software. Results: The mean age of patients was 78±6.3 years and 40.3% were female. There were 11,955 whites (88%), 453 blacks (3.3%) and 523 Hispanic patients (3.8%). Mean CHAD 2 S 2 VASc score was 4.7 in blacks, 4.6 in Hispanics and 4.5 in whites. One year mortality after watchman implantation was 6.8% in blacks, 8% in Hispanics and 7.69% in whites. After risk adjustment, compared to whites, the Hazard Ratio for death was 0.82 in blacks (p=0.31) and 0.96 in Hispanics (p=0.82). The rate of ischemic stroke and TIA following Watchman implantation was highest at 4.75 per 100 patient years in blacks followed by 2.87 per 100 patient years in Hispanics and 2.37 per 100 patient years in whites. After risk adjustment, blacks continued to have higher risk for ischemic stroke (HR 1.87, p = 0.01) compared to whites, while Hispanics had a similar risk (HR 1.19, p=0.51). Conclusions: In the Medicare population undergoing Watchman implantation, after risk adjustment, one year mortality following the procedure was similar in whites, Hispanics and blacks. However, the rate of ischemic stroke was significantly higher in blacks compared to whites even after risk adjustment. Further studies are needed in the real world to monitor the outcomes associated with watchman device in minority population.