title: Signal-averaged electrocardiographic late potentials in children with complete heart block.
abstract: The purpose of this study was to examine signal-averaged electrocardiographic (SA-ECG) late potentials to predict ventricular arrhythmias during intrinsic cardiac rhythm and during ventricular pacing in children with complete heart block (CHB). Recordings of SA-ECG were obtained from eight patients (aged 3-18 years) with documented CHB. The etiology of CHB was congenital in four cases and acquired in four cases. Six of these patients underwent permanent pacemaker implantation. Comparisons of the SA-ECG were made before and during ventricular pacing. Abnormalities of SA-ECG during intrinsic cardiac rhythm were noted in four patients, all of whom were older than 14 years. Although there was no significant difference in SA-ECG parameters between patients with congenital CHB and acquired CHB, abnormal SA-ECG was noted in one of four patients with congenital CHB and in three of four patients with acquired CHB. Two patients without permanent pacemaker implantation had normal SA-ECG, but four of six patients with permanent pacemaker implantation had abnormal SA-ECG. Three of the four patients had abnormal SA-ECG during ventricular pacing, but the abnormal SA-ECG in one patient had normalized during ventricular pacing. It is important to record SA-ECG before and during ventricular pacing to detect late potentials in patients with CHB. It may be useful to record SA-ECG while changing the pacing site to find ideal sites for electrode implantation for the potential prevention of ventricular arrhythmias.
authors.affiliation: Department of Pediatrics, University of Tokushima School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hayabuchi
authors.forename: S
authors.initials: S
authors.lastname: Matsuoka
authors.forename: M
authors.initials: M
authors.lastname: Kubo
authors.forename: H
authors.initials: H
authors.lastname: Akita
authors.forename: Y
authors.initials: Y
authors.lastname: Kuroda
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D001145:Arrhythmias, Cardiac / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D006327:Heart Block / Q000503:physiopathology*; D006801:Humans; D011237:Predictive Value of Tests