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QT dispersion in children with ventricular arrhythmia and a structurally normal heart

B R Waller1, S Balaji, X Ye

  • 1South Carolina Children's Heart Center, Medical University of South Carolina, Charleston 29425, USA.

Pacing and Clinical Electrophysiology : PACE
|March 24, 1999
PubMed

Insights

QT dispersion, a marker for sudden death risk in adults, does not appear elevated in children with idiopathic ventricular arrhythmias or benign premature ventricular contractions (PVCs). This suggests QT dispersion is not a reliable predictor of arrhythmic risk in pediatric patients with structurally normal hearts.

Area of Science:

  • Pediatric Cardiology
  • Electrophysiology
  • Cardiac Arrhythmias

Background:

  • QT dispersion is a known predictor of arrhythmic risk and sudden cardiac death in adults.
  • The role of QT dispersion in children with idiopathic ventricular arrhythmias is not well-established.

Purpose of the Study:

  • To investigate whether QT dispersion is increased in children diagnosed with idiopathic ventricular tachycardia (VT) or benign premature ventricular contractions (PVCs).
  • To determine if QT dispersion serves as a reliable marker for arrhythmic risk in pediatric patients with structurally normal hearts.

Main Methods:

  • Retrospective analysis of standard electrocardiograms (ECGs) from three groups of children: idiopathic VT (n=20), benign PVCs (n=30), and controls (n=30).
  • Comparison of QT and JT interval dispersion (QT delta, QTc delta, JTc delta) among the study groups.
  • Exclusion of patients with structural heart disease or congenital long QT syndrome.

Main Results:

  • No significant differences were observed in QTc dispersion among the idiopathic VT, benign PVC, and control groups (VT: 70±30 ms, PVC: 60±30 ms, Control: 65±30 ms).
  • Similarly, JTc dispersion did not differ significantly across the three groups (VT: 70±30 ms, PVC: 60±25 ms, Control: 70±30 ms).

Conclusions:

  • QT and JT dispersion are not significantly altered in children with idiopathic VT or benign PVCs compared to healthy controls.
  • QT dispersion is not a reliable indicator of arrhythmic risk in pediatric patients experiencing idiopathic ventricular arrhythmias without underlying structural heart disease.

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