Intraoperative modified Cox mini-maze procedure for long-standing persistent atrial fibrillation.

Background: As the most effective method of curing atrial fibrillation, the classic Maze III procedure eliminates atrial fibrillation in more than 90% of patients. In spite of high efficacy, the complexity and complications associated with this procedure prevents widespread application. In this research, we report our experience with a modified Cox mini-Maze procedure using radiofrequency energy for treating long-standing persistent atrial fibrillation during open-heart surgery.

Methods: A total of 45 patients with long-standing persistent atrial fibrillation who underwent open-heart surgery received the treatment. This modified Cox mini-Maze procedure was performed using unipolar and bipolar radiofrequency systems. Some lesions were done with unipolar pen both epicardially and endocardially to improve the transmurality of ablation.

Results: Hospital mortality was 0%. The follow-up time ranged from 6 to 26 months (mean, 16.6). Overall freedom from atrial fibrillation was 86.7% at latest follow-up after surgery. When analyzed by the Kaplan-Meier method, freedom from atrial fibrillation was 94% (6 months), 87% (12 months), and 82% (24 months). Compared with a randomized Cox Maze III control group, the results of freedom from atrial fibrillation do not show significant differences between the two groups at interval contacts. The survival rate was 100% (45 of 45), as was freedom from stroke. No patients required implantation of a permanent pacemaker. Recovery of atrial contractility occurred in 94.6% of patients (35 of 37) during the latest follow-up.

Conclusions: According to our experience, the modified Cox mini-Maze procedure allows rapid ablation application and offers an optimistic outcome for the recovery of sinus rhythm in patients with long-standing persistent atrial fibrillation who undergo open-heart surgery.