Backgrounds: Idiopathic monomorphic ventricular tachycardia (VT) occurs relatively uncommonly in children, and they are usually associated with structurally normal hearts. The purpose of this study was to evaluate the electrophysiologic characteristics and results of radiofrequency (RF) catheter ablation of idiopathic monomorphic VT in children.
Methods: A total of 19 pediatric patients (age: 16 ± 4 years, range: 8-18 years; male: female = 8: 11) with clinically documented idiopathic VT underwent an electrophysiologic study.
Results: By programmed ventricular pacing and an isoproterenol infusion in the electrophysiology laboratory, 3 pediatric patients without inducible VT were excluded. During the tachycardia, the average QRS duration calculated from all 12 leads of the 12-lead electrocardiogram was 146 ± 40 ms.
The success rate of the RF catheter ablation in this study was 85% (13/16). The RF catheter ablation for VT failed in 3 pediatric patients: 1 with right ventricular outflow tract (RVOT) VT, 1 with left ventricular outflow tract (LVOT) VT and another with idiopathic left ventricle (LV) VT. The tachycardia induced cardiomyopathy resolved after the successful RF catheter ablation in all 6 children initially associated with congestive heart failure. During a follow up period of 73 ± 35 months, there were no recurrences in any pediatric patients with successful ablation.
Conclusions: The RF catheter ablation was a safe and effective method to manage the children with idiopathic monomorphic VT. Although the number of patients was small, RF catheter ablation may be the treatment of choice for symptomatic idiopathic monomorphic VT in pediatric patients.