Long-Term Follow-Up of Idiopathic Ventricular Fibrillation in a Pediatric Population: Clinical Characteristics, Management, and Complications.

ABSTRACT

Background The natural history and long-term outcome in pediatric patients with idiopathic ventricular fibrillation ( IVF ) are poorly characterized. We sought to define the clinical characteristics and long-term outcomes of a pediatric cohort with an initial diagnosis of IVF . Methods and Results Patients were included from an International Registry of IVF (consisting of 496 patients). Inclusion criteria were (1) VF with no identifiable cause following comprehensive analysis for ischemic, electrical or structural heart disease and (2) age ≤16 years. These included 54 pediatric IVF cases (age 12.7±3.7 years, 59% male) among whom 28 (52%) had a previous history of syncope (median 2 syncopal episodes [interquartile range 1]). Thirty-six (67%) had VF in situations associated with high adrenergic tone. During a median 109±12 months of follow-up, 31 patients (57%) had recurrence of ventricular arrhythmias, mainly VF . Two patients developed phenotypic expression of an inherited arrhythmia syndrome during follow-up (hypertrophic cardiomyopathy and long QT syndrome, respectively). A total of 15 patients had positive genetic testing for inherited arrhythmia syndromes. Ten patients (18%) experienced device-related complications. Three patients (6%) died, 2 due to VF storm. Conclusions In pediatric patients with IVF , a minority develop a definite clinical phenotype during long-term follow-up. Recurrent VF is common in this patient group.