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De subitaneis mortibus. X. Familial congential heart block

T N James, R C McKone, A S Hudspeth

    Circulation
    |February 1, 1975
    PubMed

    Insights

    Congenital complete heart block in siblings was linked to abnormalities in the atrioventricular (A-V) node and His bundle. These findings offer insights into cardiac conduction development and disease.

    Area of Science:

    • Cardiology
    • Pediatric Cardiology
    • Electrophysiology

    Background:

    • Congenital complete heart block (CCHD) presents a significant challenge in pediatric care.
    • Early diagnosis and management are crucial for improving outcomes in affected infants.

    Purpose of the Study:

    • To investigate the underlying cardiac conduction system abnormalities in siblings diagnosed with congenital complete heart block.
    • To correlate pathological findings with clinical presentation and outcomes.

    Main Methods:

    • Case study of a brother and sister with CCHD.
    • Clinical evaluation including pacemaker implantation.
    • Detailed necropsy and histological examination of the heart, focusing on the atrioventricular (A-V) node, His bundle, and bundle branches.

    Main Results:

    • Both siblings presented with CCHD and required electronic pacing due to inadequate cardiac output and electrical instability.
    • The male sibling showed positive outcomes with his pacemaker.
    • The female sibling experienced fatal complications, partly attributed to pacemaker size relative to her body size.
    • Histological examination revealed primary abnormalities at the atrial septum-A-V node junction and the origin of the bundle branches.
    • Specific findings included A-V node isolation by collagen and extensive caseous degeneration in the His bundle and bundle branches, disrupting conduction.

    Conclusions:

    • Congenital complete heart block in this familial case was associated with specific structural defects in the cardiac conduction system.
    • The findings highlight the importance of understanding the development of the A-V node and His bundle in CCHD.
    • Pathological insights may inform future diagnostic and therapeutic strategies for congenital heart block.

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