Related Experiment Video

Updated: Jul 11, 2026

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

Cardiac resynchronization therapy and its potential proarrhythmic effect

Indranill Basu Ray1, Lahn Fendelander, Jagmeet P Singh

  • 1Harvard Thorndike Electrophysiology Institute, Department of Medicine, Beth Israel Deaconess Medical Center, Guidant Corporation, St. Paul, Minnesota, USA.

Clinical Cardiology
|September 8, 2007
PubMed

Insights

Cardiac resynchronization therapy (CRT) may rarely cause ventricular arrhythmias, necessitating further study. Understanding and predicting this proarrhythmic potential is crucial for individualized heart failure treatment.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Heart Failure Management

Background:

  • Cardiac resynchronization therapy (CRT) is a standard treatment for advanced chronic heart failure (CHF) with reduced left ventricular (LV) function and conduction delays.
  • While CRT improves hemodynamics and exercise capacity, rare instances of ventricular arrhythmias have been reported.

Purpose of the Study:

  • To systematically study and understand the proarrhythmic effects of CRT and left-sided pacing.
  • To develop strategies for predicting and managing ventricular tachyarrhythmia risk associated with these pacing modalities.

Main Methods:

  • This review synthesizes current research on proarrhythmia in CRT.
  • Focuses on the mechanistic understanding and predictive strategies for LV epicardial pacing.

Main Results:

  • CRT can, in rare cases, potentiate ventricular arrhythmias.
  • The risk is particularly relevant as CRT is considered for broader CHF populations and left-sided pacing is explored.

Conclusions:

  • Further investigation into the proarrhythmic potential of CRT and left-sided pacing is essential.
  • Individualized strategies are needed to predict and mitigate ventricular tachyarrhythmia risk in patients undergoing resynchronization therapy.

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