Intraoperative endocardial microwave ablation for treatment of permanent atrial fibrillation during coronary artery bypass surgery: 1-year follow-up.

Aims: Operative treatment of atrial fibrillation was initially performed as a maze operation in combination with mitral valve surgery or as a stand-alone procedure. The introduction of simplified ablation procedures led to the extension of operative atrial fibrillation treatment.

Methods And Results: In 102 consecutive patients, endocardial microwave ablation was performed during coronary artery bypass surgery alone (n = 42) or in combination with valve surgery (n = 60). Patients were divided according to lesion line concept (the initial single lesion line concept connecting the pulmonary veins with the mitral valve annulus was replaced by a box lesion line concept including the left atrial appendage) and the complexity of the procedure. Patients were followed prospectively at 1, 3, 6, and 12 months post-operatively. Survival rate was 95.8% at 30 days and 88.5% after 1 year. There were no device-related complications. At all follow-ups, approximately 10% more of the patients with the first lesion line concept and coronary bypass operation alone showed stable sinus rhythm in contrast to the combination procedures. With the new lesion line concept, patients were significantly more often in sinus rhythm at 1-year follow-up (74% vs. 52%; P = 0.0026).

Conclusion: Our results demonstrate that endocardial microwave ablation can be performed in combination with coronary artery bypass grafting with excellent conversion rate to sinus rhythm after 1 year without increasing the surgical risk for patients with permanent atrial fibrillation.