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Electrocardiographic patterns during: pacing the great cardiac and middle cardiac veins

Michael C Giudici1, Darryn W Tigrett, Jacqueline I Carlson

  • 1Genesis Heart Institute, 1236 East Rusholme, Davenport, IA 52803, USA.

Pacing and Clinical Electrophysiology : PACE
|November 3, 2007
PubMed

Insights

Electrocardiogram (ECG) patterns from pacing the great cardiac vein (GCV) and middle cardiac vein (MCV) were studied. GCV pacing typically showed left bundle branch block (LBBB) morphology, while MCV pacing consistently resulted in LBBB.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Device Technology

Background:

  • Electrocardiogram (ECG) patterns during pacing from the great cardiac vein (GCV) and middle cardiac vein (MCV) are not well characterized.
  • Understanding these patterns is crucial for interpreting cardiac resynchronization therapy (CRT) device function.

Purpose of the Study:

  • To investigate and document the distinct ECG patterns associated with pacing from the GCV and MCV.
  • To differentiate these patterns from standard left ventricular (LV) lead pacing.

Main Methods:

  • 12-lead ECGs were recorded during GCV and MCV pacing in 26 patients undergoing CRT device implantation.
  • LV leads were temporarily placed in the GCV (n=19) or MCV (n=7) before final implantation.

Main Results:

  • GCV pacing resulted in left bundle branch block (LBBB) morphology in 14 patients and right bundle branch block (RBBB) in four.
  • Distal GCV pacing and all MCV pacing sites consistently produced LBBB.
  • A RBBB pattern was observed in 125 patients with standard LV leads in lateral/posterolateral veins.

Conclusions:

  • GCV and MCV pacing yield distinct ECG patterns, primarily LBBB.
  • Knowledge of these patterns aids in troubleshooting pacing systems, especially with unintentional coronary venous lead placement.
Abstract

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