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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

Complete right bundle branch block predicts mortality in Thai patients with chronic heart failure with reduced

Wanwarang Wongcharoen1, Arintaya Phrommintikul, Rungsrit Kanjanavanit

  • 1Department of lnternal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.

Journal of the Medical Association of Thailand = Chotmaihet Thangphaet
|May 14, 2010
PubMed

Insights

In heart failure patients, right bundle branch block (RBBB) independently predicts mortality, unlike left bundle branch block (LBBB). This study clarifies the prognostic significance of different bundle branch blocks in Thai heart failure with reduced ejection fraction (HFrEF) patients.

Area of Science:

  • Cardiology
  • Internal Medicine

Background:

  • Intraventricular conduction defects are linked to increased mortality in heart failure (HF).
  • The comparative prognostic value of left bundle branch block (LBBB) versus right bundle branch block (RBBB) in HF populations remains debated.

Purpose of the Study:

  • To assess the association between bundle branch block (BBB) patterns and all-cause mortality in Thai patients with chronic heart failure with reduced ejection fraction (HFrEF).
  • To compare the predictive capabilities of RBBB and LBBB for mortality in this specific patient cohort.

Main Methods:

  • Retrospective cohort study of 170 HFrEF patients requiring hospitalization.
  • Follow-up in a heart failure clinic, with mortality predictors analyzed using Cox proportional hazard analysis.

Main Results:

  • 26% of patients had wide QRS complex (≥120 ms), including 15% with LBBB and 11% with RBBB.
  • During a mean follow-up of 1.8 years, 13% of patients died.
  • Univariate analysis identified RBBB, chronic renal insufficiency, COPD, and severe LV systolic dysfunction as mortality predictors. Multivariate analysis confirmed RBBB as the sole independent predictor (OR 3.9, p<0.05).

Conclusions:

  • Right bundle branch block (RBBB) is the only independent predictor of mortality in Thai patients with HFrEF.
  • These findings highlight the importance of identifying RBBB in HFrEF patients for risk stratification.
Abstract

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