Impact of Left Atrial Appendage Exclusion on Short-Term Outcomes in Isolated Coronary Artery Bypass Graft Surgery

Abstract

Background: The objective of this study was to evaluate the impact of LAA exclusion on short term outcomes in patients with atrial fibrillation undergoing isolated coronary artery bypass graft (CABG) surgery. Methods: We queried the 2010-2014 National Readmissions Database (NRD) for patients who underwent coronary artery bypass graft repair with and without left atrial appendage ligation using ICD-9 procedure codes (ICD-9: 36.1xx). Only patients with a history of atrial fibrillation were included in our analysis. The primary outcome of our study was 30-day readmissions following discharge. Secondary outcomes were in hospital mortality and stroke. To assess the postoperative outcomes, we utilized multivariate logistic regression models to adjust for clinical and demographic covariates. Results: In total we analyzed 253,287 CABG patients, 7.0% of whom received LAA closure. LAA exclusion was associated with a greater risk of postoperative respiratory failure (8.2% vs. 6.2%, p <.0001), acute kidney injury (21.8% vs. 18.5%, p <.0001), but did not significantly change the rate of blood transfusions or occurrence of cardiac tamponade. LAA exclusion was associated with a non-significant reduction in stroke (7.9% vs. 8.6%, p = .12), no difference in in-hospital mortality (2.2% vs. 2.2% p = .99), and a greater risk of 30-day readmission (16.0% vs. 9.6%, p < .0001) After covariate adjustment, LAA ligation remained a significant predictor of 30-day readmission (OR: 1.640, 95% CI: 1.603 - 1.677, p <.0001). Conclusions: LAA exclusion during isolated CABG in patients with AF is associated with a higher rate of 30-day readmission. Post-operative measures to mitigate the loss of the hormonal and hemodynamic effects of the LAA may increase the therapeutic benefit of this procedure.