Intraoperative radiofrequency maze ablation for atrial fibrillation: The Berlin modification

Background. The Cox-maze procedure combined with an operation for organic h eart disease is highly successful in the elimination of chronic atrial fibr illation. However, it prolongs significantly the aortic cross-clamp and ope rating time. In this study, a simplified left atrial maze procedure, which is a short procedure performed using a surgical radiofrequency ablation pro be, is added to elective open heart procedures in patients with atrial fibr illation. Methods. Forty-eight adults with atrial fibrillation (duration, 6 months to 36 years) underwent elective open heart operations (isolated valve procedu res or coronary artery bypass grafting, n = 27 patients; combined procedure s, n = 21 patients) combined with intraoperative radiofrequency ablation of the left atrium. The postoperative follow-up period ranged from 1 to 11 mo nths (mean, 4 months). Possible predictors for persistent postoperative atr ial fibrillation were determined among 40 variables by univariate and multi variate analyses. Results. Intraoperative radiofrequency ablation prolonged the aortic cross- clamp time for 6 to 14 minutes (mean, 11 minutes). Freedom from atrial fibr illation was 100% intraoperatively, 25% at 1 week after operation (12 of 48 patients), 59% at 1 month postoperatively (16 of 27 patients), 64% at 3 mo nths postoperatively (16 of 25 patients), and 92% at 6 months postoperative ly (12 of 13 patients). The only predictor of postoperative atrial fibrilla tion was the presence of coronary artery disease (odds ratio, 7.5; 80% conf idence interval, 2.24-25.13). Conclusions. Intraoperative radiofrequency ablation of the left atrium comb ined with an operation for organic heart disease effectively eliminates atr ial fibrillation without significant prolongation of the aortic cross-clamp and operative time. The presence of coronary artery disease decreases the success rate during the first 6 postoperative months. (C) 2001 by The Socie ty of Thoracic Surgeons.