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Updated: Jul 9, 2026
07:56
A Model of Long-Term Ventricular Fibrillation in Isolated Rat Hearts
Published on: February 17, 2023
Altered ventricular stretch contributes to initiation of cardiac memory
Eugene A Sosunov1, Evgeny P Anyukhovsky, Michael R Rosen
1Center for Molecular Therapeutics, Department of Pharmacology, College of Physicians and Surgeons of Columbia University, New York, New York 10032, USA.
Heart Rhythm
|December 7, 2007
Summary
Altered ventricular contraction patterns, not just activation, initiate cardiac memory. This phenomenon, observed in rabbit hearts, highlights the role of mechanical changes in T-wave morphology after pacing.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Mechanics
Background:
- Cardiac memory is a T-wave morphology change after ventricular pacing or arrhythmias.
- Altered ventricular activation and contraction patterns influence T-wave configuration.
Purpose of the Study:
- To investigate the role of altered contractile patterns in initiating cardiac memory.
- To understand the mechanical basis of T-wave changes post-pacing.
Main Methods:
- Isolated rabbit hearts were perfused and paced from the atrium or ventricle.
- Quasi-ECG leads recorded T-wave vector displacement.
- Ventricular load and contractility were manipulated.
Main Results:
- Ventricular pacing induced T-wave vector displacement, resolving within 10 minutes.
- Reduced ventricular load or contractility diminished T-wave displacement.
- Epicardial stretch mimicked pacing-induced T-wave changes.
Conclusions:
- Altered ventricular contractile patterns and stretch initiate cardiac memory.
- Mechanical factors play a crucial role in T-wave memory formation.
- Ventricular activation alone does not fully explain cardiac memory.
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