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
Case selection for cardiac resynchronization in atrial fibrillation.
John G F Cleland1, Freidoon Keshavarzi, Pierpaolo Pellicori
1Department of Cardiology, Castle Hill Hospital, Hull York Medical School, University of Hull, Kingston-upon-Hull HU6 5JQ, UK.
Heart Failure Clinics
|September 24, 2013
Summary
Cardiac resynchronization therapy (CRT) shows limited effectiveness in patients with atrial fibrillation (AF). Current evidence suggests CRT benefits are primarily seen in patients with normal heart rhythm, not those with AF.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- Cardiac resynchronization therapy (CRT) is a treatment for heart failure.
- Landmark CRT trials often excluded patients with atrial fibrillation (AF).
- Atrioventricular (AV) resynchronization was hypothesized as a key mechanism for CRT benefits.
Purpose of the Study:
- To evaluate the effectiveness of CRT in patients with atrial fibrillation (AF).
- To determine if biventricular resynchronization offers benefits independent of AV resynchronization in AF patients.
Main Methods:
- Analysis of data from landmark clinical trials, specifically examining outcomes in patients with and without AF.
- Comparison of CRT efficacy in patients with AF versus those in sinus rhythm.
Main Results:
- A key trial demonstrated significant CRT benefit in patients with sinus rhythm.
- The same trial showed no significant benefit from CRT in patients with AF.
- Limited evidence supports biventricular resynchronization as a primary benefit mechanism over AV resynchronization in AF.
Conclusions:
- Current evidence suggests CRT is not effective for most patients with atrial fibrillation.
- The benefits of CRT may be largely dependent on AV synchrony, which is disrupted in AF.
- Further research is needed to clarify the role of CRT in specific patient subgroups with AF.
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