Impact of Cox maze procedure on outcome in patients with atrial fibrillation and mitral valve disease

Objective: We sought to determine whether the Cox maze procedure provides additional benefit to patients with atrial fibrillation undergoing mitral valve operations. Methods: Between May 1992 and August 2000, we performed 258 Cox maze procedures with mitral valve replacement (n = 147) or mitral valve repair (n = 1 11). We compared the outcomes of these patients with those of 61 control patients with preoperative atrial fibrillation who underwent mitral valve replacement alone during the same interval. The three cohorts were similar in age, sex, and proportion of patients in preoperative New York Heart Association functional class 3 or 4. Results: Although 5-year survivals were similar among the groups (94% for mitral valve replacement alone, 95% for mitral valve replacement plus maze, and 97% for mitral valve repair plus maze), freedoms from atrial fibrillation at 5 years were significantly higher in the mitral valve replacement plus maze group (78%) and the mitral valve repair plus maze group (81%) than in the mitral valve replacement group (6%, P < .0001). Freedoms from stroke at 5 years were 97% for the mitral valve replacement plus maze group, 97% for the mitral valve repair plus maze group, and only 79% for mitral valve replacement group (P < .0001). Multivariable analysis with Cox hazard model revealed that the most significant risk factor for late stroke was the omission of the Cox maze procedure (P = .003). Conclusions: The addition of the Cox maze procedure to mitral valve repair and replacement was safe and effective for selected patients. Elimination of atrial fibrillation significantly decreased the incidence of late stroke.