Randomized feasibility trial of prophylactic radiofrequency ablation to prevent atrial fibrillation after cardiac surgery

Abstract

Objective: To evaluate the feasibility of prophylactic radiofrequency isolation of the pulmonary veins, with left atrial appendage amputation, to reduce the incidence of postoperative atrial fibrillation after cardiac surgery in patients aged 70 years and older.

Methods: The Federal Food and Drug Administration granted an investigational device exemption to utilize a bipolar radiofrequency clamp for prophylactic pulmonary vein isolation in a limited feasibility trial. Sixty-two patients without prior dysrhythmias were prospectively randomized to undergo either their index cardiac surgical procedure or bilateral pulmonary vein isolation and left atrial appendage amputation during their cardiac operation. The primary outcome was occurrence of in-hospital postoperative atrial fibrillation. Subjects were on 24-hour telemetry until discharge. Dysrhythmias, any episode of atrial fibrillation >30 seconds, were confirmed by electrophysiologists blinded to the study.

Results: Sixty patients, mean age 75 years and mean Congestive heart failure, Hypertension, Age (>65 = 1, >75 = 2 points), Diabetes, previous Stroke/Transient ischemic attack (2 points), Vascular disease, Gender (female) score of 4, were analyzed. Thirty-one patients randomized to control and 29 to the treatment group. The majority of patients in each group underwent isolated coronary artery bypass grafting. No perioperative complications related to the treatment procedure, need for permanent pacemaker, or mortality occurred. The in-hospital incidence of postoperative atrial fibrillation was 55% (17 out of 31) in the control group and 7% (2 out of 29) in the treatment group (P < .001) The control group had a significantly higher requirement for antiarrhythmic medications at discharge: 45% (14 out of 31) versus 7% (2 out of 29) in the treatment group (P < .001).

Conclusions: Prophylactic radiofrequency isolation of the pulmonary veins with left atrial appendage amputation during the primary cardiac surgical operation reduced the incidence of postoperative atrial fibrillation in patients aged 70 years and older with no history of atrial arrhythmias.

Keywords: ablation; atrial fibrillation; cardiac surgery; postoperative.