Long-Term Follow-Up After Radiofrequency Catheter Ablation of Accessory Atrioventricular Pathways in Children

OBJECTIVES The purpose of this study was to evaluate long-term safety and efficacy of catheter ablation of accessory atrioventricular pathways (AP) in a pediatric cohort. BACKGROUND Radiofrequency catheter ablation of accessory AP is the recommended treatment for patients with atrioventricular re-entrant tachycardia. Data on long-term results $1 year after AP ablation in pediatric patients is sparse. METHODS A total of 296 patients <18 years of age who had undergone radiofrequency-AP ablation between October 2002 and June 2015 were included into the study. Follow-up was >1 year in all patients. Median age at ablation had been 11.6 years, and median follow-up was 5.6 years. Recurrence of AP conduction after ablation was defined as documentation of pre-excitation, supraventricular tachycardia attributable to AP, or proof of AP conduction during repeat electrophysiological study. RESULTS AP ablation succeeded in 268 of 296 individuals (91%). After successful ablation, recurrence of AP conduction was observed in 29 of 268 individuals (10.8%). Of those 29, 23 (79%) had AP recurrence within the first year after ablation, whereas 13 (45%) had recurrence of AP conduction already within the first month. Six patients had late recurrence of AP conduction >1 year post-ablation. Procedural success and freedom from AP conduction after a single ablation procedure was 86% at 1 month, 83% at 1 year, and 81% at 5 years after ablation. CONCLUSIONS After radiofrequency ablation of AP in children, recurrence of AP conduction occurred in 23 subjects (8% of the study cohort) within the first year after ablation. Late recurrences >1 year after ablation were noticed in 6 children (2% of the study group), highlighting the need for longer follow-up >1 year. Results of the present study on late AP recurrence should be taken into account whenever families are counselled for pediatric AP ablation. (C) 2018 by the American College of Cardiology Foundation.