Improved outcomes in CABG patients with atrial fibrillation associated with surgical left atrial appendage exclusion

Background We sought to determine the impact of left atrial appendage clip exclusion (LAACE) on coronary artery bypass grafting (CABG) outcomes among patients with pre-existing atrial fibrillation (AF). Methods From October 1, 2015 to October 1, 2017, 4210 Medicare beneficiaries with pre-existing AF underwent isolated CABG (i.e., without ablation) with (n = 931) or without (n = 3279) LAACE. Inverse probability of treatment weighting was used to evaluate the effect of concomitant LAACE on short- and long-term outcomes after CABG. Long term risks of thromboembolism and mortality were assessed using competing-risk regression and Cox proportional hazard models. Results Operative mortality, length of stay, and 30-day readmission did not differ between groups. Thromboembolism risk was 26% lower for the CABG + LAACE group compared with isolated CABG over a 2-year time-to-event analysis (sub hazard ratio [sHR] 0.74, 95% confidence interval [CI] 0.54-1.00, p = .049). There were no differences in ischemic stroke rates. All-cause mortality risk was 45% lower for CABG + LAACE during the late follow-up period (91-730 days; HR 0.55, 95% CI 0.32-0.95, p = .031). The late period annual absolute all-cause mortality rate was 3.7% for CABG + LAACE and 6.9% for isolated CABG. There were lower readmission rates (31% vs. 43%, p < .001) and total inpatient days (4.0 days vs. 7.2 days, p < .01.) for the CABG + LAACE during follow-up. Total hospital in and out-patient treatment costs were similar between groups through one year. Conclusions Concomitant LAA exclusion via an epicardial closure device is associated with reduced CABG mortality, thromboembolic events, and readmissions in patients with pre-existing atrial fibrillation.