Mitral valve replacement with or without a concomitant Maze procedure in patients with atrial fibrillation

Abstract

BACKGROUND: Although the Maze procedure is regarded as the most effective way to restore sinus rhythm in patients with chronic atrial fibrillation (AF), it remains unclear whether this procedure offers long-term clinical benefits in patients undergoing mechanical valve replacement. METHODS AND RESULTS: Between 1999 and 2007, 402 patients with AF-associated mitral valve (MV) disease underwent MV replacement with a mechanical prosthesis. Of these patients, 159 underwent valve replacement plus the Maze procedure, whereas 243 received valve replacement alone. The composite end points of cardiac death and cardiac-related morbidities were compared in these two groups using the inverse-probability-of-treatment-weighted method. At a median follow-up time of 63.1 months (range 0.2-123.9 months), patients who had undergone the Maze procedure were at significantly lower risk of thromboembolic events (hazard ratio (HR)=0.26, 95% confidence interval (CI) 0.07 to 0.95; p=0.041) and were at comparable risk of death (HR=0.96, 95% CI 0.44 to 2.07; p=0.907) and cardiac death (HR=1.26, 95% CI 0.53 to 3.01; p=0.598) compared with patients who underwent MV replacement alone. The composite risk of death or major events was lower in the Maze procedure group (HR=0.64, 95% CI 0.38 to 1.08; p=0.093). CONCLUSIONS: Compared with MV replacement alone, the addition of the Maze procedure was associated with a reduction in thromboembolic complications and better long-term event-free survival in patients with AF undergoing mechanical MV replacement. Prospective randomised data are necessary to confirm the findings of this study.