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Updated: Jun 25, 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
The basic pacing rate in CRT patients: the higher the better?
Frederik Voss1, Ruediger Becker, Melanie Hauck
1Department of Cardiology, University of Heidelberg, Heidelberg, Germany. frederik_voss@med.uni-heidelberg.de
Summary
Optimizing the basic pacing rate for cardiac resynchronization therapy (CRT) in patients with sinus bradycardia can improve cardiac output (CO). A pacing rate between 60-70 bpm is suggested to enhance CO without affecting stroke volume (SV).
Area of Science:
- Cardiology
- Biomedical Engineering
Background:
- Cardiac resynchronization therapy (CRT) optimization often involves AV and VV intervals.
- Basic pacing rate programming in CRT is typically empirical.
- Sinus bradycardia presents unique challenges for CRT optimization.
Purpose of the Study:
- To systematically evaluate the impact of basic pacing rate on hemodynamic parameters in CRT patients with sinus bradycardia.
- To determine the optimal basic pacing rate for maximizing hemodynamic benefit in this patient group.
Main Methods:
- Seventy patients with moderate to severe heart failure and appropriate indications for CRT were included.
- Electrical velocimetry (EV) was used to measure cardiac output (CO) and stroke volume (SV).
- Hemodynamic measurements were taken at four pacing rates: 40, 50, 60, and 70 bpm.
Main Results:
- Cardiac output (CO) increased with higher pacing rates, showing statistical significance between 70 bpm and 40 bpm.
- Stroke volume (SV) remained consistent across all tested pacing rates.
- Patients had moderate to severe heart failure, LVEF ≤35%, and QRS duration >120 ms.
Conclusions:
- Increasing the basic pacing rate from 40 to 70 bpm enhances CO in CRT patients with sinus bradycardia.
- This enhancement in CO occurs without a reduction in SV.
- A basic pacing rate of 60-70 bpm appears reasonable for optimizing hemodynamics in this population.
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