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.