Related Experiment Video
Updated: May 7, 2026
12:45
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
Will biventricular pacing replace right ventricular pacing for antibradycardia therapy?
1Florida Heart Rhythm Institute, 5 Tampa General Circle, Tampa, FL 33606, USA.
Expert Review of Medical Devices
|September 24, 2013
Summary
Biventricular pacing (BiV) is superior to right ventricular pacing (RV) in preventing heart failure progression and left ventricular dysfunction. Upgrading to BiV pacing can improve existing RV pacing-induced dysfunction.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Cardiac resynchronization therapy (CRT) benefits heart failure patients with conduction delays.
- Conventional right ventricular (RV) pacing may lead to adverse left ventricular (LV) remodeling and dysfunction.
Purpose of the Study:
- To evaluate the long-term effects of biventricular (BiV) pacing versus RV pacing in patients with atrioventricular block and systolic dysfunction.
- To compare LV remodeling, function, and heart failure progression between BiV and RV pacing.
Main Methods:
- Analysis of data from randomized trials, including the BLOCK-HF study.
- Comparison of outcomes based on pacing type (BiV vs. RV) irrespective of baseline QRS duration.
Main Results:
- Long-term RV pacing is associated with more LV remodeling, dysfunction, and heart failure compared to BiV pacing.
- These detrimental effects of RV pacing can occur even with normal LV ejection fraction (LVEF) and are reversible with upgrading to BiV pacing.
Conclusions:
- BiV pacing is recommended over RV pacing for patients with atrioventricular block and systolic dysfunction to prevent adverse LV remodeling and heart failure.
- Potential future indications for CRT include diastolic dysfunction and conditions like hypertrophic cardiomyopathy, though challenges like complications and cost remain.
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