Effect of surgery for atrial fibrillation associated with mitral valve disease

The purpose of this study is to evaluate the effect of surgery for atrial fibrillation (AF) associated with mitral valve disease.

From September 1994 to December 2006, 244 patients who underwent mitral valve surgery were enrolled in this study. The maze procedure or pulmonary vein isolation was concomitantly performed in 147 patients, while the remaining 97 patients were not surgically treated for AF. The patients were divided into 3 groups based on their cardiac rhythm at discharge from the hospital: the sinus group (108 patients), the intractable AF group (39 patients), and the untreated AF group (97 patients). The clinical features and late results of patients were compared among these groups.

Early mortality rate was 0.7% and no major morbid events had occurred. Follow-up was completed in 95.6% of the patients and the mean follow-up period was 6.03 years. Actuarial survival was not significant between the sinus and AF groups. Actuarial freedom from thromboembolism at 5 and 10 years was 96.5% in the sinus group, 82.4% and 78.1%, respectively, in the intractable AF group, and 93.4% and 89.1%, respectively, in the untreated AF group; statistical significance was observed among the 3 groups (p = 0.01). By means of multivariate analysis, intractable AF was found to be the only risk factor for thromboembolism and other complications.

Atrial fibrillation associated with mitral valve disease should be treated, because restoration of the sinus rhythm might lead to a lower incidence of thromboembolism and valve-related complications in the later period.