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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

Mortality risk associated with bundle branch blocks and related repolarization abnormalities (from the Women's Health

Zhu-ming Zhang1, Pentti M Rautaharju, Elsayed Z Soliman

  • 1Epidemiological Cardiology Research Center, Department of Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA. zmzhang@wfubmc.edu

The American Journal of Cardiology
|August 4, 2012
PubMed

Insights

Electrocardiographic bundle branch block (BBB) increases cardiac and all-cause death risk. Left BBB (LBBB) and right BBB (RBBB) predict coronary heart disease (CHD) death, with LBBB also predicting all-cause death in women with existing cardiovascular disease.

Area of Science:

  • Cardiology
  • Epidemiology
  • Public Health

Background:

  • Electrocardiographic bundle branch block (BBB) is linked to increased mortality.
  • Existing research on the association between BBBs and mortality in general populations is conflicting.

Purpose of the Study:

  • To evaluate the risk of coronary heart disease (CHD) and all-cause death associated with left BBB (LBBB) and right BBB (RBBB).
  • To analyze these risks in a large cohort of women over 14 years.

Main Methods:

  • Utilized Cox proportional-hazards regression for mortality risk analysis.
  • Included 66,450 participants from the Women's Health Initiative (WHI) study.
  • Adjusted models for demographic and clinical risk factors.

Main Results:

  • In women with cardiovascular disease (CVD), LBBB and RBBB predicted CHD death. LBBB also predicted all-cause death.
  • In CVD-free women, only LBBB predicted CHD death.
  • ST J-point depression in lead aVL was an independent predictor of CHD death in women with LBBB.

Conclusions:

  • Prevalent LBBB in CVD-free women and both LBBB and RBBB in women with CVD are significant predictors of CHD death.
  • ST J-point depression in lead aVL is a strong independent predictor of CHD death in women with LBBB.

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