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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
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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

Clinical Research in Cardiology : Official Journal of the German Cardiac Society
|February 17, 2009
PubMed

Insights

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.
Abstract

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