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Pacing-induced electromechanical ventricular dyssynchrony does not acutely influence right ventricular function and

Mark K Friedberg1, Anne M Dubin, George F Van Hare

  • 1Division of Pediatric Cardiology, Department of Pediatrics, Stanford University, Stanford, California 94304, USA.

Journal of Cardiovascular Electrophysiology
|November 20, 2008
PubMed

Insights

In children with healthy hearts, pacing-induced electromechanical dyssynchrony did not acutely impact right ventricular (RV) function or hemodynamics. This suggests RV function is not acutely affected by dyssynchrony in pediatric patients with normal cardiac structure.

Area of Science:

  • Pediatric Cardiology
  • Electrophysiology
  • Cardiac Physiology

Background:

  • Right ventricular (RV) pacing can negatively affect ventricular function.
  • The acute impact of electromechanical dyssynchrony on RV function in children is not well understood.

Purpose of the Study:

  • To investigate the acute effects of RV apical and RV outflow pacing-induced electromechanical dyssynchrony on RV function and hemodynamics in children with normal hearts.

Main Methods:

  • Seventeen children with normal cardiac structure underwent RV apical and RV outflow pacing.
  • Electromechanical synchrony, hemodynamic response, and RV function were assessed using ECG, tissue Doppler imaging, and pressure-tipped transducers.

Main Results:

  • Pacing induced significant electromechanical dyssynchrony, evidenced by prolonged QRS duration and increased interventricular delay.
  • Despite induced dyssynchrony, global and regional RV systolic and diastolic functions remained preserved.
  • Hemodynamics, including blood pressure and cardiac index, were not acutely altered.

Conclusions:

  • Pacing-induced electromechanical dyssynchrony does not acutely impair RV function or hemodynamics in children with normal cardiac structure.
  • Electromechanical dyssynchrony may be a more critical therapeutic target in patients with pre-existing decreased RV function.
Abstract

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