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The paced electrocardiogram cannot be used to identify left and right ventricular pacing sites in cardiac

Anders Sommer1, Mads Brix Kronborg2, Christoffer Tobias Witt2

  • 1Department of Cardiology, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, Aarhus N DK-8200, Denmark a.sommer@dadlnet.dk.

Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups on Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology
|December 7, 2014
PubMed

Insights

Paced electrocardiogram (ECG) characteristics do not reliably confirm left ventricular (LV) and right ventricular (RV) pacing sites in cardiac resynchronization therapy (CRT). Current ECG methods are insufficient for precise lead placement verification.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Imaging

Background:

  • Accurate left ventricular (LV) and right ventricular (RV) lead placement is crucial for effective cardiac resynchronization therapy (CRT).
  • Validation of paced electrocardiogram (ECG) characteristics against known lead positions is lacking.

Purpose of the Study:

  • To assess if paced QRS morphology can differentiate between various LV and RV pacing sites.
  • To use cardiac computed tomography (CT) as the gold standard for determining LV and RV pacing locations.

Main Methods:

  • Evaluated QRS morphology during LV-only and RV-only pacing in 97 CRT patients.
  • Assessed lead positions using a 16-segment LV model and 6-segment RV model with cardiac CT.
  • Excluded patients with LV lead displacement or non-free wall pacing from LV analysis.

Main Results:

  • LV free wall pacing correlated with superior and right-axis deviation (P=0.02, P=0.04).
  • Basal LV pacing produced later precordial QRS transition compared to mid-LV pacing (P=0.001).
  • No significant associations found between RV pacing site and QRS axis or transition; varying morphologies seen from identical myocardial segments.

Conclusions:

  • Limited associations exist between LV/RV pacing sites and paced QRS axis.
  • Paced QRS characteristics are unreliable for confirming specific LV and RV pacing sites in CRT patients.
Abstract

Keywords:
Cardiac computed tomographyCardiac resynchronization therapyElectrocardiogramLeft ventricular pacing siteRight ventricular lead position

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