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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

Inotropic contractile reserve and response to cardiac resynchronization therapy in patients with markedly remodeled

Farooq A Chaudhry1, Ajay Shah, Sripal Bangalore

  • 1St. Luke's-Roosevelt Hospital and Columbia University, New York, New York 10025, USA. fchaudhr@chpnet.org

Journal of the American Society of Echocardiography : Official Publication of the American Society of Echocardiography
|December 4, 2010
PubMed

Insights

Inotropic contractile reserve (ICR) predicts cardiac resynchronization therapy (CRT) response better than dyssynchrony. Dobutamine stress echocardiography can identify patients likely to benefit from CRT, improving treatment selection.

Area of Science:

  • Cardiology
  • Echocardiography
  • Heart Failure Management

Background:

  • Current echocardiographic indicators for ventricular dyssynchrony lack sensitivity/specificity for predicting cardiac resynchronization therapy (CRT) response.
  • Inotropic contractile reserve (ICR) assesses myocardial viability and predicts functional improvement in cardiomyopathy.
  • The predictive role of ICR in CRT patients with significant left ventricular remodeling is currently unknown.

Purpose of the Study:

  • To evaluate the efficacy of inotropic contractile reserve (ICR) in predicting response to cardiac resynchronization therapy (CRT).
  • To assess ICR's predictive value in patients with markedly remodeled left ventricles undergoing CRT.

Main Methods:

  • Fifty-four patients referred for CRT underwent low-dose dobutamine stress echocardiography.
  • ICR was defined as improved contractility in over five of 16 left ventricular segments.
  • Patients were monitored for CRT response, defined by a 5-point increase in ejection fraction.

Main Results:

  • Inotropic contractile reserve (ICR) was a superior predictor of CRT response (AUC=0.94) compared to dyssynchrony (AUC=0.74).
  • ICR significantly predicted response (OR=2.84, P<.0001) and provided incremental value beyond QRS duration and dyssynchrony.
  • The presence of ICR improved the predictive model's area under the curve from 0.47 to 0.93.

Conclusions:

  • Inotropic contractile reserve (ICR) is a stronger predictor of cardiac resynchronization therapy (CRT) response than current markers like dyssynchrony and QRS duration.
  • ICR offers incremental prognostic value, potentially improving patient selection for CRT.
  • Dobutamine stress echocardiography utilizing ICR may be crucial for identifying CRT responders, warranting further multicenter validation.
Abstract

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