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High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation
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Published on: July 29, 2011

[Problems of fascicular asyncronism in advanced left bundle branch blocks with marked axial deviation towards the

P Alboni, C Malacarne

    Giornale Italiano Di Cardiologia
    |January 1, 1976
    PubMed

    Insights

    Advanced left bundle branch blocks with left axis deviation often indicate significant heart issues like cardiomegaly and heart failure. This deviation may signal asynchronous left ventricular activation due to anterior fascicular block.

    Area of Science:

    • Cardiology
    • Electrophysiology
    • Medical Imaging

    Context:

    • Focuses on patients with advanced left bundle branch blocks (LBBB) and left axis deviation (LAD) (> -45 degrees).
    • Investigates the clinical, radiological, and vectocardiographic findings in these patients.
    • Highlights the frequent presence of marked cardiomegaly and severe congestive heart failure.

    Purpose:

    • To explore the potential link between left axis deviation in LBBB and asynchronous left ventricular activation.
    • To investigate if ECG findings, specifically delayed intrinsicoid deflection in lead aVL compared to V6, indicate anterior fascicular block.
    • To discuss other potential causes of LAD in advanced LBBB.

    Summary:

    • Studied 12 patients with advanced LBBB and LAD, finding significant cardiomegaly and heart failure in half.
    • Hypothesizes LAD results from asynchronous left ventricular activation due to anterior fascicle lesions.
    • Observed the proposed ECG sign (delayed aVL vs. V6 intrinsicoid deflection) in only two patients, suggesting other causes for LAD in LBBB.

    Impact:

    • Contributes to understanding the complex electrocardiographic manifestations of LBBB.
    • May refine diagnostic criteria for identifying specific conduction abnormalities in heart disease.
    • Informs clinical assessment and management of patients with advanced LBBB and associated cardiac conditions.

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