Definitive therapy of idiopathic right ventricular arrhythmias (VA) remains a challenge in interventional electrophysiology. The aim of this study was to evaluate the utility of EnSite Velocity system in the catheter ablation of RV tachycardia in children.

Thirty-five children with idiopathic right VA underwent catheter ablation procedure using the EnSite Velocity system guidance.

The mean patient age was 12.0 ± 3.7 years and the mean patient weight was 43.6 ± 18.7 kg. The origin of right VA was divided into right ventricular outflow tract (RVOT) (30 patients) and other right ventricular localizations (five patients). The mean procedure and fluoroscopy times were 175 ± 67 min and 2.35 ± 1.89 min, respectively. No fluoroscopy was used in 19 patients. Acute success was achieved in 29 patients (83 %). The focus of VA was epicardial in three failed procedures. Cryocatheter (6-mm or 8-mm tip) was used in six patients, radiofrequency ablation (RFA) (4-mm or 8-mm tip) in 26 patients, and 4-mm tip irrigated RFA in three patients. During a mean follow-up of 15.9 ± 7.1 months, ventricular tachycardia recurred in six patients (20 %). There were three complications (transient atrioventricular block developed in one patient during parahissian cryoablation and two patients developed transient complete right bundle branch block).

Catheter ablation of idiopathic right VA in children can be performed safely and effectively with limited fluoroscopy using the EnSite Velocity system.