Mid-term results of the box pulmonary vein isolation and the cryo-maze procedure for chronic atrial fibrillation associated with mitral valve disease.

PURPOSE: We performed box pulmonary vein isolation and the modified Maze procedure using cryoablation (cryo-maze) to eliminate chronic atrial fibrillation (AF) associated with mitral valve disease from 1999 to 2004. This article compares the elimination rate of chronic AF and the postoperative occurrence of new atrial tachycardia after both procedures over a follow-up period of >5 years.

METHODS: A total of 75 patients were enrolled in the study. Among them, 40 patients underwent box pulmonary vein isolation for chronic AF concomitant with solitary mitral valve surgery. Another 35 patients underwent the cryo-maze procedure for chronic AF concomitantly with both mitral and tricuspid valve surgeries. We evaluated the postoperative AF elimination rate and the occurrence of atrial tachycardia.

RESULTS: During a total of 622.5 patient-years of followup, AF disappeared in 26 of 40 (65%) patients after the box pulmonary vein isolation and in 26 of 35 (74%) patients after the cryo-maze procedure at 5 years. Common atrial flutter occurred in 2 of 40 (5.0%) patients after the pulmonary vein isolation procedure. Left atrial tachycardia occurred in 1 (2.9%) and right atrial tachycardia in 1 (2.9%) of 35 patients after the cryo-maze procedure.

CONCLUSION: The cryo-maze procedure was rather effective for eliminating chronic AF associated with both mitral and tricuspid valve disease, but there were a few cases with new atrial tachycardia. The box pulmonary vein isolation was useful in solitary mitral valve cases.