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Updated: Oct 23, 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

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Catheter induced distal intra-Hisian right bundle branch block in a patient with persistent proximal intra-Hisian

P Santarelli, F Bellocci, F Loperfido

    Pacing and Clinical Electrophysiology : PACE
    |May 1, 1981
    PubMed

    Insights

    This study details a patient with complete atrioventricular (AV) block and narrow QRS who developed catheter-induced right bundle branch block. Pacing revealed distinct His bundle lesions, suggesting multilevel His bundle pathology.

    Area of Science:

    • Cardiology
    • Electrophysiology
    • Cardiac Anatomy

    Background:

    • Complete intra-Hisian atrioventricular (AV) block presents diagnostic challenges.
    • Electrophysiological studies are crucial for understanding complex conduction abnormalities.

    Observation:

    • A patient with complete intra-Hisian AV block and narrow QRS developed catheter-induced right bundle branch block (RBBB) during an electrophysiological study.
    • Selective His bundle pacing demonstrated differential effects based on stimulation site.

    Findings:

    • Distal His bundle pacing normalized the QRS complex in the setting of complete AV block and RBBB.
    • Proximal His bundle stimulation revealed persistent RBBB, indicating a proximal His bundle lesion.
    • These findings suggest a focal lesion in the distal His bundle caused the catheter-induced RBBB.

    Implications:

    • This case is the first to document multilevel lesions within the His bundle in humans.
    • Understanding His bundle anatomy and potential lesion sites is critical for interpreting electrophysiological findings.
    • Highlights the importance of precise catheter manipulation during His bundle pacing.

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