Randomized study of surgical isolation of the pulmonary veins for correction of permanent atrial fibrillation associated with mitral valve disease

Abstract

Objective: Chronic permanent atrial fibrillation is often due to mitral valve disease. The Cox maze procedure is the gold standard for treating this arrhythmia. Simpler techniques and ablation methods should have their efficacy tested in clinical practice. Our objective was to evaluate the effectiveness of surgical pulmonary vein isolation as compared with the Cox maze procedure.

Methods: Sixty patients were randomly assigned to control group, modified maze group (Cox maze III), and surgical isolation of the pulmonary veins (SPVI) group from July 1999 to October 2004. All patients had mitral valve lesions treated concomitantly. Preoperative characteristics were similar between groups.

Results: There were 4 deaths: 3 in the Cox maze group and 1 in the SPVI group (P = .31). The Cox maze group presented longer times of extracorporeal circulation and myocardial ischemia (P < .001). The relative risk of late postoperative development of atrial fibrillation was 0.07 in the SPVI group (P < .001; 95% confidence intervals: 0.02-0.27) and 0.195 in the Cox maze group (P = .002; 95% confidence intervals: 0.07-0.56) as compared with the control group. No difference was found between the SPVI and Cox maze groups concerning prevention of atrial fibrillation recurrence (relative risk: 0.358; P = .215; 95% confidence intervals: 0.08-1.67).

Conclusions: The modified Cox maze procedure and surgical pulmonary vein isolation were similarly effective in restoring sinus or regular rhythm in permanent atrial fibrillation associated with mitral valve disease. These results favor the adoption of surgical isolation as a preferable technique, simpler and equally effective in controlling atrial fibrillation. The results also can bring further information for understanding the mechanisms involved in origins and treatment of chronic permanent atrial fibrillation.