Long-term outcome of modified maze procedure combined with mitral valve surgery: analysis of outcomes according to type of mitral valve surgery.

OBJECTIVE

Efficacy of the maze procedure for atrial fibrillation associated with advanced mitral disease not amenable to repair has not been determined. This study investigated whether type of mitral surgery affects maze outcome.

METHODS

From January 1999 to January 2007, a total of 435 patients underwent the maze procedure and concomitant mitral operation. Of these, 226 underwent mitral repair and 209 underwent mitral replacement.

RESULTS

Median follow-up was 40.6 months (0.4-111.3 months), with 25 deaths and 6 strokes. Nineteen patients did not regain normal sinus rhythm. There were no significant intergroup differences in survival, stroke incidence, or sinus rhythm restoration rate. Among 427 early survivors, 64 had late atrial fibrillation recurrence. Five-year atrial fibrillation-free rates were 80.9% + or - 3.7% in the repair group and 77.3% + or - 4.1% in the replacement group (P = .099). By multivariate analysis, age at surgery older than 60 years (P = .045), fine atrial fibrillation wave pattern (P = .033), and preoperative left atrial dimension greater than 60 mm (P = .019) were independent risk factors for atrial fibrillation recurrence, whereas type of mitral surgery was not (P = .573). Although transmitral A-wave prevalence did not differ significantly between groups beyond the early postoperative period, A-wave velocity was faster in the repair group through the entire postoperative period (P < .001).

CONCLUSIONS

Maze outcomes were acceptable regardless of type of mitral surgery. Late atrial fibrillation recurrence was mainly affected by age, unfavorable electrocardiographic characteristics of atrial fibrillation, and larger preoperative left atrial size.