Endocardial microwave ablation in patients following mitral valve surgery

Atrial fibrillation not only impairs the quality of life in patients, it is also associated with higher mortality and morbidity caused by embolic events or therapeutic anticoagulation treatment. The present prospective registry study evaluated the conversion rates and the influencing factors on outcomes of mitral valve surgery and concomitant microwave ablation in 191 patients with permanent atrial fibrillation. Approximately 60% of the patients remained in sinus rhythm during the postoperative period whereas, depending on the study data, conversion rates between 4% and 33.5% have been reported after cardiac surgery alone without additional surgical rhythm control. Significant influencing factors on postoperative sinus rhythm were the presence of diabetes mellitus or a history of myocardial infarction, the preoperative atrial size, and tendentially, surgery duration. There were no ablation-related complications. During the 1.5-year follow-up it became clear that prolonged surgery duration (in most cases due to operative complexity with greater risk) and postoperative recurrence of atrial fibrillation were significant factors influencing mortality.