Intraoperative treatment of chronic atrial fibrillation with ultrasound

Aim. The purpose of this retrospective study is to evaluate the efficacy of intraoperative atrial compartmentalization utilizing ultrasound (US) energy in selected patients with chronic atrial fibrillation (CAF). Methods.From March 1999 to June 2000, 27 patients with ages ranging from 15 to 69 (mean 44.62′15.61 years), 15 of whom were female, underwent intraoperative atrial compartmentalization with US. Mitral valve replacement was performed in 22 patients, mitral valve repair in 4 and 1 patient with paroxysmal atrial fibrillation (AF) underwent isolated atrial compartmentalization. The compartmentalization procedure was started using an ultrasonic device (Ultracision®) at the level of the right atrium on cardiopulmonary bypass (CPB) and with beating heart, and then, after the mitral valve procedure, the ablation-lines were traced in an inverted U-shape, involving the 4 pulmonary veins. All patients were given verapamil or amiodarone for electrical atrial remodeling for 6 months. Results. Time of surgery was 166 min on average, that is approximately 79 min of CPB, 59 min of aortic cross-clamping, 12.5 min for right atrial lesion lines and 14 min for the left ones. After weaning CPB, all the patients maintained adequate cardiac output. Immediate reversion to sinus rhythm was achieved in 24 patients (88.8%). A small intraoperative left atrial wall rupture due to the ablation technique was easily repaired by a direct continuous suture. Another complication observed in 1 patient was a sternal instability, which was fixed successfully. Two patients died because of postoperative respiratory failure due to bilateral pneumonia in 1 case and low cardiac output, complicated by septicemia. The pharmacological anti-arrhythmic treatment was stopped 6 months after surgery. During 29 months of follow-up, 20 patients (74%) were still in sinus rhythm. Conclusion. The use of US during mitral valve operation in patients with CAF allowed for easy and rapid reestablishment of the sinus rhythm. This technique modifies and makes the Maze procedure easier, decreases surgical time and the incidence of postoperative complications.