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Evolution of paced QRS and QTc intervals in children with epicardial pacing leads

Maren Tomaske1, Paul Harpes, Rene Prêtre

  • 1Division of Pediatric Cardiology, University Children's Hospital, Steinwiesstrasse 75, 8032, Zurich, Switzerland. maren.tomaske@kispi.uzh.ch

Clinical Research in Cardiology : Official Journal of the German Cardiac Society
|August 10, 2007
PubMed

Insights

Permanent ventricular pacing in children does not cause significant increases in paced QRS or QTc intervals over time. This suggests that age-related electrical activation changes are unlikely to cause ventricular dysfunction in pediatric patients receiving pacing.

Area of Science:

  • Pediatric Cardiology
  • Electrophysiology
  • Cardiac Pacing

Background:

  • Permanent ventricular pacing in children can lead to ventricular dysfunction due to asynchronous activation.
  • The long-term impact of pacing on QRS and QTc intervals in pediatric populations remains unclear.

Purpose of the Study:

  • To investigate whether paced QRS and QTc intervals increase disproportionately over time in children undergoing permanent ventricular pacing.
  • To determine if right ventricular (RV) pacing or left ventricular (LV) pacing affects interval changes differently.

Main Methods:

  • Analysis of 52 children with epicardial leads, followed for up to 12.2 years.
  • Patients were grouped into RV (n=21) and LV (n=31) pacing groups.
  • Calculation of Z-scores for paced QRS and QTc intervals, and regression slope coefficients (incline(i)) to assess interval changes over time, correcting for age.

Main Results:

  • Mean Z-scores for paced QRS intervals remained stable over follow-up in both RV and LV pacing groups.
  • The regression slope coefficients (incline(i)) for paced QRS and QTc intervals did not differ significantly between RV and LV pacing groups.
  • Limited interval changes over time were observed, indicating no disproportionate prolongation.

Conclusions:

  • Epicardial pacing of either the right or left ventricle in children does not result in disproportionate increases in paced QRS or QTc intervals.
  • Age-related prolongation of electrical activation is unlikely to be the cause of ventricular dysfunction in these patients.
Abstract

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