Ventricular arrhythmias in children: the validity of exercise stress tests for their diagnosis and management

One hundred ninety-six children ranging in age from 4 years to 15 years with premature ventricular contraction (PVC) on a resting electrocardiogram (ECG) underwent exercise tests and 29 of them were found to have significant ventricular arrhythmias. They included 8 patients with 2 PVC's in row, 8 patients with 3-4 PVC's in row, and 13 patients with more than 5 PVC's in row (ventricular tachycardia: VT). These 29 patients were evaluated with exercise tests by two-step exercise ECG (TSE) and by treadmill (TM), and with 24 hour continuous ECG monitoring (Holter monitoring). 141 ECG's, 77 TSE's, 77 TM's and 46 Holter monitoring were obtained in total, and the incidence of the each study revealing findings compatible with the final diagnosis was 3%, 15%, 51% and 26%, respectively. For detection of 2 PVC's in row, the sensitivity of TSE and TM was not different, but for picking up 3-4 PVC's in row and VT, TM was significantly superior to TSE. Among the VT patients, there were a few cases in whom neither TM nor Holter monitoring alone was sufficient to confirm the diagnosis. Children with symptoms suggestive of ventricular arrhythmias should be carefully evaluated with a combination of exercise tests and Holter monitoring.