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Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
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Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Published on: July 3, 2013

Effect of verapamil on retrograde ventriculo-atrial conduction in children

I A Kashani, J G Shakibi, B Siassi

    Japanese Heart Journal
    |July 1, 1980
    PubMed

    Insights

    Verapamil, a slow channel blocker, was studied in children undergoing cardiac catheterization. It was found to abolish retrograde atrioventricular (V-A) conduction, potentially explaining its antiarrhythmic effects on reentrant arrhythmias.

    Area of Science:

    • Cardiology
    • Electrophysiology
    • Pharmacology

    Background:

    • Retrograde atrioventricular (V-A) conduction plays a role in reentrant arrhythmias.
    • Verapamil is a potent antiarrhythmic drug and a slow channel blocker.
    • Understanding verapamil's effect on V-A conduction is crucial for managing certain cardiac arrhythmias.

    Purpose of the Study:

    • To investigate the effects of verapamil on retrograde V-A conduction in pediatric patients.
    • To determine if verapamil can abolish or prolong retrograde V-A conduction.
    • To correlate the observed effects with verapamil's antiarrhythmic properties.

    Main Methods:

    • A study involving 12 children undergoing diagnostic cardiac catheterization.
    • Administration of a single intravenous dose of verapamil (0.15 mg/Kg).
    • Electrophysiological recordings including surface EKG, intra-atrial, and His bundle electrograms before and after verapamil administration.
    • Right ventricular pacing with extra stimulus technique was employed.

    Main Results:

    • Verapamil prolonged the AH interval in 9 out of 12 children.
    • Retrograde V-A conduction was abolished in 5/12 children and prolonged in 1/12.
    • In all cases where retrograde V-A conduction was present, its duration exceeded antegrade conduction time.

    Conclusions:

    • Verapamil effectively abolishes retrograde V-A conduction when present.
    • This abolition of retrograde V-A conduction may contribute to verapamil's antiarrhythmic efficacy in reentrant arrhythmias.
    • Verapamil demonstrates significant impact on cardiac electrophysiology, particularly concerning V-A pathways.

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