Implantable loop recorder monitoring after concomitant surgical ablation for atrial fibrillation (AF): insights from more than 200 continuously monitored patients

Abstract

Different follow-up methods have been used to report success rates after 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) in a large patient cohort. Between 09/2008 and 12/2012, 343 cardiac surgical patients underwent concomitant surgical AF ablation. ILR implantation was performed in 206 patients. ILR interrogation was accomplished at 3, 6 and 12months postoperatively. Successful ablation was defined as AF Burden<0.5%. Primary outcome of the study was freedom from AF at 12-month follow-up. Mean patient's age was 70.5±7.4years. 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%. Freedom from AF rate after 1-year follow-up was 68.5 and 63.6% off antiarrhythmic drugs, respectively. Statistically significant predictors for successful ablation at 1-year follow-up were smaller LA diameter, shorter duration of AF and preoperative paroxysmal AF. Demographic data, indication for surgery, lesion set and used energy source had no impact on freedom from AF after 1year. Continuous ILR monitoring after concomitant surgical AF ablation was safe and feasible, with registered freedom from AF rate of 68.5% at 1-year follow-up. Thus continuous rhythm monitoring provides reliable outcome data and helps to guide antiarrhythmic therapy.