Objective: To observe the short and mid-term therapeutic effects of Bi-polar ablation systems for intraoperative treatment of atrial fibrillation (AF).
Methods: From March 2005 to January 2007, 91 patients received intraoperative treatment of atrial fibrillation with Bi-polar ablation systems, including 5 cases of paroxysmal atrial fibrillation and 86 persistent/permanent cases. The main concomitant heart diseases were rheumatic mitral valve diseases. Atricure Dry Ablation System was used for 37 cases and Cardioblate Irrigated Ablation System for 54 cases. The ablation lesion patterns included Cox-maze III, Modified Cox Mini-maze and Left-sided Maze.
Results: Mean ablation time was (14.1+/-6.7) min. No ablation-related complications occurred. Three patients died perioperatively. Two patients had permanent pacemaker implantation 3 months after operation. One case suffered from stroke and lower limb thrombosis 2.5 years after operation. Follow-up lasted for 6 to 29 months. The none-AF rhythm were 62.5%, 85.2%, 79.0% and 74.5% at discharge, 3 months, 6 months, and>or=12 months respectively. Compared to Uni-polar Ablation therapy group, the restoration of sinus rhythm in Bi-polar group were significantly higher at 6 months and>or=12 months postoperatively. The latest follow-up results indicated that 100% of preoperative paroxysmal atrial fibrillation patients restored sinus rhythm and 75.3% of persistent/permanent patients were free from atrial fibrillation. The none-AF rhythm of Atricure group (81.1%) showed no difference from the Cardioblate (77.5%). Meanwhile there were no significant differences among the three ablation lesion groups.
Conclusion: Intraoperative radiofrequency ablation with Bi-polar systems is a feasible, safe and highly effective surgical option compared to the Uni-polar ablation technique.