Three years experience with monopolar and bipolar radiofrequency ablation surgery in patients with permanent atrial fibrillation

Objective: In our population permanent atrial. fibrillation (pAF) is a frequent concomitant problem in patients undergoing open heart surgery. A 3-year experience with a treatment strategy using mono- and bipolar radio-frequency (RF) ablation procedures in a heterogeneous group of patients is reported. Methods: In a prospective analysis the incidence of pAF among all. patients undergoing open heart surgery in our department between February 2001 and July 2004 was evaluated. In a second step a selective group of 106 patients with pAF (primary mitral: n = 63; aortic: n = 24; CABG: n = 16; aortic + mitral: n = 3) underwent either monopolar (n = 86) or bipolar (n = 20) RF ablation procedures creating two encircling isolation lesions around the left and the right pulmonary veins (PVs) and a connection tine between both. In addition amiodarone was given for 3 months after surgery. Regular follow-ups were performed 3, 6, 9, 12, 18, 24 and 36 months after surgery. Results: The incidence of pAF in the total group of 4.110 patients was 3.6%. White the rate was low in cases without severe heart valve disease (1.1%), a significantly higher presence of pAF in patients scheduled for heart valve surgery (10.3%) was observed (P < 0.0001). The incidence was 30-39% in patients with degenerative and rheumatic mitral valve (MV) disease, and further particularly high in the older aged compared to younger patients (4.2 - 8.3% at 70 - 99 years; P < 0.001). Hospital mortality after combined open heart and RF ablation surgery was 1.9%. Whereas patients with small left atrial size (LA-diameters < 56 mm; n = 59) had SR in almost 90% at follow-up, LA enlargement (LA-diameter greater than or equal to56 mm; n = 47) was associated with a significant risk of persisting pAF after surgery (P = 0.033, 0.002 and 0.006 at 3, 6 and 9 months follow-up). Conclusion: The use of RF ablation procedures in combination with amiodarone therapy represents a safe and efficient option to cure pAF during open heart surgery in a selective group of patients. The preoperative LA size was of significant importance for the outcome in this investigation. (C) 2004 Elsevier B.V. All rights reserved.