Safety and efficacy of transcatheter cryoablation of septal accessory pathways with three-dimensional mapping without fluoroscopy in children

In this study, we analyzed the success rate of cryoablation for septal accessory pathways in pediatric patients using a three-dimensional mapping method. 102 pediatric patients underwent septal accessory pathway ablation, with cryoablation performed for an average of 4 minutes in each application using a 6 or 8-mm cryoablation catheter with three-dimensional mapping. The mean age and weight of the patients were 11.3 ± 5.4 years and 35.6 ± 14.3 kg, respectively. Most patients (70.6%) had a manifest accessory pathway, while 29.4% had a concealed one. The locations of the accessory pathways were anteroseptal (37.3%), midseptal (22.5%), and posteroseptal (40.2%). The successful ablation effect time was 8.9 ± 7.3 seconds. Two patients experienced early recurrence on the day after the procedure, but the second procedure was successful in both cases. Throughout the course of the procedure, nodal rhythm manifested in five individuals, representing 4.9% of the sample; incomplete right bundle branch block was observed in four patients, accounting for 3.9% of the cohort; prolongation of the PR interval occurred in four cases, making up 3.9% of the total; and second-degree atrioventricular block was identified in two patients, constituting 1.9% of the study population. These electrocardiographic (ECG) changes returned to normal the following day, except for two patients with right bundle branch block, whose ECG findings returned to normal within the first month. The mean follow-up period was 56.71 ± 29.5 months, during which recurrence was observed in two patients with manifest preexcitation in the first and third months after the procedure. However, a second ablation procedure was successfully performed in these patients, and no second recurrence was detected during the follow-up period. Cryoablation with electroanatomic mapping system is a safe and effective procedure with high success rates in pediatric patients with septal and perinodal accessory pathways.

Three-dimensional mapping; Cryoablation; Septal accessory pathway; Children

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