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Updated: Jul 11, 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
Physiology of biventricular pacing.
Kenneth C Bilchick1, Robert H Helm, David A Kass
1Division of Cardiology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
Current Cardiology Reports
|September 20, 2007
Summary
Cardiac resynchronization therapy (CRT) improves survival in heart failure patients with dyssynchrony. CRT effectively addresses mechanical dyssynchrony, leading to electrical, mechanical, and molecular left ventricular remodeling.
Area of Science:
- Cardiology
- Biomedical Engineering
Background:
- Heart failure with dyssynchrony is a significant clinical challenge.
- Biventricular pacing, or cardiac resynchronization therapy (CRT), is an established treatment.
- Recent trials demonstrate improved survival outcomes with CRT.
Purpose of the Study:
- To differentiate between electrical and mechanical dyssynchrony.
- To investigate the predictive value of intraventricular mechanical dyssynchrony for CRT response.
- To explore the molecular underpinnings of mechanical dyssynchrony and its impact on ventricular arrhythmias.
Main Methods:
- Quantification of electrical dyssynchrony via QRS duration.
- Assessment of intraventricular mechanical dyssynchrony and its impact on septal and lateral wall mechanics.
- Analysis of molecular changes associated with mechanical dyssynchrony, including connexin-43, stress kinases, and TNF-alpha.
Main Results:
- Intraventricular mechanical dyssynchrony is a stronger predictor of CRT response than interventricular dyssynchrony.
- Mechanical dyssynchrony correlates with molecular derangements (connexin-43, stress kinases, TNF-alpha).
- These molecular changes may contribute to conduction abnormalities and ventricular arrhythmias.
Conclusions:
- CRT effectively corrects abnormal regional wall stresses.
- Biventricular pacing promotes beneficial electrical, mechanical, and molecular left ventricular remodeling.
- Understanding mechanical dyssynchrony is crucial for optimizing CRT in heart failure patients.
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