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Updated: Mar 24, 2026

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
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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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[LEFT HIS BUNDLE BRANCH BLOCK ASSOCIATED WITH LEFT VENTRICULAR TORSION AND REDUCED EJECTION FRACTION]

E N Pavlyukova, D A Kuzhel', G V Matyushin

    Klinicheskaia Meditsina
    |March 19, 2016
    PubMed

    Insights

    Left His bundle branch block (LBBB) significantly impairs left ventricular (LV) torsion and increases mechanical desynchronization in cardiomyopathy patients. This study reveals LBBB negatively affects LV electrical activation and contractility, leading to abnormal torsion.

    Area of Science:

    • Cardiology
    • Electrophysiology
    • Cardiac Mechanics

    Context:

    • Left His bundle branch block (LBBB) is common in cardiomyopathy patients.
    • Its impact on left ventricular (LV) torsion and mechanics is not fully understood.
    • Cardiomyopathy is defined as LV ejection fraction less than 40%.

    Purpose:

    • To evaluate the influence of LBBB on LV torsion.
    • To assess the hemodynamic consequences of LBBB-induced changes in LV torsion.
    • To investigate the relationship between LBBB, LV rotation, and mechanical desynchronization.

    Summary:

    • Sixty-four cardiomyopathy patients (ischemic and dilated) were studied, divided into groups with narrow and LBBB (middle QRS duration: 153 ms).
    • Despite similar LV contractility, LBBB patients exhibited significantly reduced LV rotation and torsion (2.95 ± 3.34 vs. 5.87 ± 3.83, p < 0.01).
    • LBBB was associated with more abnormal unidirectional rotation (50% vs. 21.9%, p < 0.001) and greater posterior wall contractility delay (63.3 ± 35.1 ms vs. 8.0 ± 17.9 ms, p < 0.001), indicating increased mechanical desynchronization.

    Impact:

    • LBBB negatively affects LV electrical activation and contractility.
    • LBBB results in abnormal LV torsion and increased mechanical desynchronization.
    • Findings highlight the detrimental role of LBBB in cardiac mechanics for cardiomyopathy patients.

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