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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

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Role of rate control and regularization through pacing in patients with chronic atrial fibrillation and preserved

Gianfranco Ciaramitaro1, Giuseppe Sgarito, Francesco Solimene

  • 1Institute of Cardiology, University of Palermo, Italy. gciaramitaro@freemail.it

Pacing and Clinical Electrophysiology : PACE
|August 23, 2006
PubMed

Insights

The Ventricular Rate Regulation (VRR) algorithm stabilizes heart rate in chronic atrial fibrillation patients without increasing pacing. This improves rate recovery after exercise and promotes better autonomic balance.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Devices

Background:

  • High heart rates in chronic atrial fibrillation (CAF) contribute to hemodynamic alterations and tachycardiomyopathies.
  • Patients with CAF, preserved ventricular function, and symptomatic pauses may require pacemaker (PM) implantation.
  • Ventricular rate variability (VRR) is a key consideration in managing CAF patients.

Purpose of the Study:

  • To evaluate the effect of the VRR algorithm on ventricular rate regularization in CAF patients.
  • To assess VRR's impact on hemodynamic stability and autonomic balance.
  • To compare VRR algorithm performance against fixed-rate pacing.

Main Methods:

  • Fifty-eight patients with CAF underwent a crossover study comparing VRR algorithm ON versus OFF.
  • Patients received pacemakers (PM) with the VRR algorithm (INSIGNIA pacemakers, Guidant Corp.).
  • Measurements included mean ventricular rate (MR), rate variability (RR30), and post-exercise rate recovery (SLOPE) during a 6-minute walk test.

Main Results:

  • The VRR algorithm significantly decreased heart rate variability (RR30: -7.36 +/- 8.8; P < 0.01).
  • No significant increase in mean ventricular rate was observed (MR: -1.11 +/- 8.3; P = NS).
  • Significant improvement in rate recovery after exercise was noted (SLOPE: +15.41 +/- 16.8; P < 0.01).

Conclusions:

  • The VRR algorithm effectively stabilizes ventricular rate in CAF patients.
  • VRR improves rate recovery post-exercise without increasing pacing rate above spontaneous rhythm.
  • The algorithm promotes a more favorable autonomic balance.
Abstract

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