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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

Relationship of baseline electrocardiographic characteristics with the response to cardiac resynchronization therapy

Matthew R Reynolds1, Lilian P Joventino, Mark E Josephson

  • 1Division of Cardiology, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA. mreynold@bidmc.harvard.edu

Pacing and Clinical Electrophysiology : PACE
|November 18, 2004
PubMed

Insights

Identifying patients unlikely to benefit from cardiac resynchronization therapy (CRT) for congestive heart failure (CHF) is crucial. Prior anterior infarction on ECG and lower baseline VO2 predict diminished CRT response, aiding efficient patient selection.

Area of Science:

  • Cardiology
  • Medical Devices
  • Heart Failure Management

Background:

  • Cardiac resynchronization therapy (CRT) is a key treatment for congestive heart failure (CHF).
  • Predicting patient response to CRT is essential for optimizing treatment efficiency.
  • Identifying non-responders can prevent unnecessary interventions and costs.

Purpose of the Study:

  • To identify preimplantation electrocardiogram (ECG) variables that predict response to CRT in patients with CHF.
  • To investigate the correlation between ECG indicators, such as RBBB and prior myocardial infarction, and CRT outcomes.
  • To determine which clinical and ECG factors are associated with improved peak oxygen consumption (VO2) after CRT.

Main Methods:

  • Analysis of preimplantation ECGs from 110 patients in the MIRACLE ICD trial with CHF and left ventricular systolic dysfunction.
  • Patients were randomized to active biventricular pacing.
  • Change in peak oxygen consumption (Delta-VO2) from baseline to 6 months was the primary outcome measure, evaluated alongside clinical and ECG variables.

Main Results:

  • Average peak VO2 improved from 13.4 to 14.3 mL/kg per minute.
  • Reduced exercise time and lower baseline VO2 were the strongest predictors of increased Delta-VO2.
  • ECG findings of a dominant R wave in lead aVR, RBBB, and prior anterior infarction were associated with smaller improvements in Delta-VO2 in univariate analysis.
  • In multivariate analysis, only baseline VO2 and ECG evidence of prior anterior infarction significantly predicted the outcome.

Conclusions:

  • ECG markers, specifically prior anterior infarction, may help identify congestive heart failure patients unlikely to benefit from biventricular pacing.
  • Baseline VO2 is a significant predictor of CRT response.
  • Further research is needed to validate these predictors and explore other factors influencing CRT therapeutic response.

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