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Updated: Aug 14, 2026
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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Dispersion of repolarization in cardiac resynchronization therapy
Bart Hooft van Huysduynen1, Cees A Swenne, Jeroen J Bax
1Department of Cardiology, Leiden University Medical Center, The Netherlands.
Heart Rhythm
|December 20, 2005
Summary
Cardiac resynchronization therapy (CRT) pacing does not increase transmural dispersion of repolarization (TDR). ECG repolarization indices reflect activation sequences, not TDR, in patients receiving CRT.
Area of Science:
- Cardiology
- Electrophysiology
- Biomedical Engineering
Background:
- Cardiac resynchronization therapy (CRT) can cause proarrhythmic effects due to increased transmural dispersion of repolarization (TDR).
- Identifying patients vulnerable to TDR via ECG repolarization indices is a potential strategy.
Purpose of the Study:
- To evaluate if ECG repolarization indices can quantify TDR during different CRT pacing modes.
- To investigate the relationship between pacing-induced activation and TDR.
Main Methods:
- Compared ECG repolarization indices across biventricular, left ventricular (LV), and right ventricular (RV) pacing in 28 heart failure patients.
- Utilized the ECGSIM mathematical model to simulate CRT effects on repolarization and TDR.
Main Results:
- ECG repolarization indices (T-wave interval, amplitude, area, complexity) varied with pacing mode, correlating with activation sequences.
- Simulations confirmed that repolarization patterns mirrored depolarization patterns.
- No significant difference in average or local TDR was found between biventricular, LV, and RV pacing modes.
Conclusions:
- ECG repolarization indices in CRT patients primarily indicate pacing-induced activation sequences, not TDR.
- CRT pacing, including biventricular and LV, does not elevate TDR compared to conventional RV pacing.
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