Ablation of atrial fibrillation using microwave energy--early experience

Between Dec 12, 2002 and Aug 22, 2004, 84 operative patients with chronic atrial fibrillation (AF) were subjected to AF ablation with microwave energy. Of these, 49 patients were female; their ages ranged between 20 and 72 years (mean, 43.1 years). Most patients suffered from mitral disease, accompanied in over one third of cases with tricuspid insufficiency. Thirteen patients had aortic valve disease, mostly with mitral involvement. Three patients had coronary artery disease, three had atrial septal defect and one had a left atrial (LA) myxoma. Seventy-two patients underwent endocardial ablation and 12 patients underwent epicardial ablation. Operative mortality was 4 (4.8%), and there were no major untoward postoperative events. Fifty seven patients (71.3%) had their AF converted to sinus rhythm immediately after surgery. Amiodarone or sotalol was used in all postoperative patients for 6 months, except in 8 who had bradycardia. Electrical defibrillation was utilized in cases of atrial flutter or persistent AF. Seventy patients were followed for at least 6 months. In total, 52 of them (74.3%) are still in sinus rhythm. We believe microwave ablation is a satisfactory and safe method of AF ablation, and because it is brief, it can be added to surgical procedures without undue risk to the patient.