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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

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Prognostic Impact of QRS Axis Deviation in Patients Treated With Cardiac Resynchronization Therapy

Laura Perrotta1, Jagdesh Kandala2, Luigi DI Biase3

  • 1University of Florence, Florence, Italy.

Journal of Cardiovascular Electrophysiology
|December 8, 2015
PubMed

Insights

QRS axis deviation in heart failure patients with left bundle branch block undergoing cardiac resynchronization therapy indicates a worse prognosis. Both left and right axis deviation are independent predictors of adverse clinical outcomes.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Heart Failure Management

Background:

  • Cardiac resynchronization therapy (CRT) selection relies on QRS duration and morphology.
  • Left bundle branch block (LBBB) is a key indicator for CRT benefit.
  • The prognostic value of QRS axis deviation (AD) in LBBB patients undergoing CRT requires further investigation.

Purpose of the Study:

  • To assess the prognostic impact of QRS axis deviation (AD) in heart failure (HF) patients with LBBB undergoing CRT.
  • To determine if AD influences clinical outcomes in this patient population.

Main Methods:

  • Retrospective analysis of 707 HF patients with LBBB who received CRT.
  • Classification of baseline QRS axis into normal (NA), left axis deviation (LAD), and right axis deviation (RAD).
  • Evaluation of the primary endpoint (all-cause death/HF hospitalization) using Kaplan-Meier and Cox proportional hazard analyses.

Main Results:

  • 46% had NA, 51% LAD, and 3.5% RAD.
  • RAD patients (52%) had the highest event rate, followed by LAD (40%) and NA (30%).
  • Both LAD (HR: 1.40) and RAD (HR: 2.49) were independently associated with worse clinical outcomes.

Conclusions:

  • QRS axis deviation (both left and right) in LBBB patients with HF undergoing CRT predicts a poorer prognosis.
  • AD is an independent predictor of adverse clinical outcomes in this cohort.
  • This finding may refine patient selection for CRT.
Abstract

Keywords:
QRS axis deviationcardiac resynchronization therapyheart failureleft bundle branch block

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