Abstract 17275: Clinical Outcomes Following Maze and Left Atrial Appendage Occlusion Procedures for Patients With Atrial Fibrillation Undergoing Mitral Valve Surgeries: Insights From the National Readmission Database

Abstract

Background: Maze procedure and left atrial appendage occlusion (LAAO) are often done as adjunctive procedures during mitral valve surgery in patients with atrial fibrillation (AF). We examined the effect of the Maze procedure and LAAO on AF-related clinical outcomes. Methods: We identified patients with AF from the Nationwide Readmission Database who underwent mitral valve surgery in the years 2016-2019 using ICD 10 codes. Patients were grouped by procedure type (Maze+/LAAO+, Maze+/LAAO-, Maze-/LAAO+, Maze-/LAAO- (control)). Outcomes were in-hospital and 180-day readmission rate for stroke and mortality, and 180-day AF/atrial flutter readmission. Multivariate regression analysis was conducted adjusting for demographics, hospital characteristics, comorbidities, and cardiac surgery type. Results: Of 14,979 patients with AF who underwent mitral valve surgery, adjunctive procedures were performed as follows: 2427 Maze+/LAAO+, 997 Maze+/LAAO-, 4052 Maze-/LAAO+, and 7503 Maze-/LAAO-. Stroke during the index admission and within 180 days occurred less frequently in the adjunctive procedure groups than in control group (2.5%, 2.3%, 3.4%, and 4.9% respectively, P<0.001). Similar results were observed for in-hospital and 180-day mortality (3.9%, 7.6%, 4.8%, and 6.8% respectively, P<0.001). However, readmission within 180 days for AF/atrial flutter was higher in the adjunctive procedure groups than the control group (5.6% vs 4.2% vs 5.4% vs 3.8%, P<0.001). On multivariate analysis, patients who had either Maze or LAAO procedures (Maze+/LAAO+, Maze+/LAAO-, Maze-/LAAO+) had a lower 180-day stroke risk when compared to the control group (hazard ratio (HR) 0.7, P=0.01; HR 0.66, P=0.55; and HR 0.79, P=0.01 respectively). Similarly, 180-day mortality was lower in patients who underwent LAAO compared to the control group (HR 0.71, P=0.002; HR 1.27, P=0.05; and HR 0.78, P=0.004 respectively). Conclusion: Patients with AF who underwent Maze and/or LAAO procedures during mitral valve surgery had lower 180-day stroke and mortality rates. There was a higher rate of readmission for AF/atrial flutter, which may be a short-term proarrhythmic effect of these procedures or may reflect differences in AF type and rhythm control goals in the control group.