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Ventricular repolarization during uni and biventricular pacing in normal subjects.

Abdel J Fuenmayor¹, María Eugenia Delgado

¹Electrophysiology and Arrhythmias Section, Cardiovascular Research Institute Abdel M. Fuenmayor P, University of The Andes, Mérida, Venezuela. ajf@cantv.net

International Journal of Cardiology

|August 20, 2011

Summary

Cardiac pacing affects the depolarization-repolarization process (D-REPP). Biventricular pacing causes less D-REPP disturbance than single-chamber pacing, impacting intervals like QRS and QT.

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Area of Science:

Cardiology
Electrophysiology

Background:

Cardiac depolarization-repolarization (D-REPP) can vary with pacing mode and lead placement.
Understanding these variations is crucial for optimizing cardiac pacing strategies.

Purpose of the Study:

To evaluate how different cardiac pacing modes (right, left, biventricular) influence D-REPP.
To compare electrophysiological intervals during pacing versus sinus rhythm.

Main Methods:

31 patients with normal cardiac function were studied.
12-lead ECGs were recorded during right, left, and biventricular pacing.
Measurements included QRS, QT, corrected QT (cQT), peak-to-end of T wave (PETW), and PETW/QT ratio.

Main Results:

All pacing modes increased D-REPP intervals compared to sinus rhythm.
Right and left ventricular pacing similarly increased intervals.
Biventricular pacing also increased intervals, but to a lesser extent than univentricular pacing.

Conclusions:

Cardiac pacing significantly alters D-REPP in patients without structural heart disease.
Univentricular pacing (right or left) showed no significant differences.
Biventricular pacing results in less perturbation of the cardiac depolarization-repolarization process.