Pediatric Cardiology and Cardiac Surgery
Vol.26 No.4 2010 (324-327)
Department of Pediatrics, Aomori Prefectural Central Hospital, Aomori, Japan
Background: Some children with idiopathic nonsustained ventricular tachycardia (NSVT) have persistent arrhythmia and become candidates for catheter ablation. Polymorphism is a predictive factor of poor prognosis in ventricular tachycardia. In this study, the implications of polymorphism for outcomes in children with NSVT were investigated.
Methods: Twenty-two children (12 boys and 10 girls) with NSVT, who were followed by Holter monitoring, were enrolled. Patients with apparent moderate to severe underlying heart diseases were excluded. Based on NSVT morphology, the patients were divided into two groups (polymorphic 7 children, monomorphic 15 children) and clinical findings of the two groups were retrospectively compared. Poor outcome was defined as persistent NSVT in the last Holter monitoring or indication for catheter ablation because of drug-resistant arrhythmia.
Results: The median age of all patients at diagnosis and the median follow-up period were 12 years and 9.5 months, and 1 year and 11.5 months, respectively. Follow-up periods and percentage of patients treated with drugs were not significantly different in the two groups. The prevalence rate of children with poor outcomes was significantly higher in the polymorphic than the monomorphic group (57% vs. 7%, p=0.021).
Conclusions: The results suggested that most children with polymorphic NSVT were resistant to therapy.