Clinical outcomes of mortality, readmissions, and ischemic stroke among medicare patients undergoing left atrial appendage closure via implanted device

Importance: Left atrial appendage closure (LAAC) has emerged as a nonpharmacological alternative for stroke prevention in patients with nonvalvular atrial fibrillation. Contemporary data regarding the characteristics and outcomes of patients undergoing this procedure are limited. Objective: To determine the characteristics, postprocedural mortality rate, and rates of readmission and ischemic stroke among Medicare beneficiaries who underwent LAAC via implanted device. Design, Setting, and Participants: This population-based cohort study used Medicare inpatient claims from January 2015 to December 2017 for 13627 patients aged older than 65 years with a diagnosis of atrial fibrillation who underwent LAAC with an implanted device from January 2015 to November 2017. Data analyses were conducted from January through August 2019. Exposure: Left atrial appendage closure. Main Outcomes and Measures: Mortality rates during the index admission and for 1 year after LAAC were assessed. The 30-day readmission rate and the primary reasons for readmission were also examined. In addition, the likelihood of hospitalization for ischemic stroke within 180 days among 9231 patients for whom 6 months of follow-up data were available was evaluated. Results: Among the 13627 patients undergoing LAAC, the mean (SD) age was 78.0 (6.3) years, 9406 (69.0%) were older than 75 years, 11980 (87.9%) were white, and 5630 (41.3%) were women. The mean (SD) CHA₂DS_2-VASc score was 4.3 (1.4). Twenty-eight patients (0.2%) died during the index admission. Mortality rates were 0.6% (80 patients) at 30 days, 1.9% (262 patients) at 90 days, 4.0% (547 patients) at 180 days, and 7.5% (1027 patients) at 365 days. The 30-day readmission rate among 13599 patients discharged alive was 9.4% (1284 patients). Among 9231 patients with 6 months of follow-up data, 111 (1.2%) experienced readmission for ischemic stroke or transient ischemic attack within 180 days of discharge. Conclusions and Relevance: In this cohort study of patients older than 65 years with atrial fibrillation who underwent LAAC with an implanted device, readmission rates for ischemic strokes over the course of 6 months were lower than expected given the patients' CHA₂DS_2-VASc scores in the absence of anticoagulation therapy. Mortality at 1 year was higher than that reported in previous randomized clinical trials, likely because the patients in the present study were older, had a higher number of comorbidities, and were ineligible to receive warfarin.