306 * IMPLANTABLE LOOP RECORDER MONITORING AFTER CONCOMITANT SURGICAL ABLATION FOR ATRIAL FIBRILLATION: INSIGHTS FROM MORE THAN TWO HUNDRED CONTINUOUSLY-MONITORED PATIENTS

Abstract

Objectives: Different follow-up methods have been used to report success rates after atrial fibrillation (AF) ablation. Recent studies have shown that intermittent rhythm monitoring underestimates the actual AF recurrence rate. We therefore report our experience with continuous rhythm monitoring by implantable loop recorder (ILR) monitoring in a large patient cohort. Methods: Between September 2008 and December 2012, 343 cardiac surgical patients underwent concomitant surgical AF ablation. ILR implantation was performed in 206 patients. ILR interrogation was accomplished 3, 6 and 12 months postoperatively. Successful ablation was defined as AF burden <0.5%. The primary outcome of the study was sinus rhythm (SR) at 12-month follow-up. Results: Mean patient age was 70.5 ± 7.4 years, 73.8% were male. No major ablation- or ILR-related complications occurred. In 4 patients (1.9%) ILR had to be explanted due to ILR-related wound infection (n = 2) or chronic pain (n = 2). Survival rate at 1-year follow-up was 96.6%. Overall sinus rhythm conversion rate after 1-year follow-up was 68.5% and 63.6% off antiarrhythmic drugs. Patients with preoperative paroxysmal AF had significantly higher SR rate at 12-month follow-up (75.9% vs 59.1%; P = 0.014). Demographic data, indication for surgery, lesion set and energy source used had no impact on SR rate after 1 year. Mean AF burden in patients with failure of ablation was 33.1 ± 23.1% and mean time spent in AF was 7.9 h/day. Conclusion: Continuous ILR monitoring after concomitant surgical AF ablation was safe and feasible, and provided SR rate of 68.5 % at 1-year follow-up. Continuous rhythm monitoring helps to guide antiarrhythmic therapy and allows for safer withdrawal of anticoagulation therapy.