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Electrophysiologic effects of disopyramide in children

I A Kashani, J G Shakibi, B Siassi

    Japanese Heart Journal
    |July 1, 1980
    PubMed

    Insights

    Disopyramide effectively treats arrhythmias in children with congenital heart disease by prolonging atrial and AV nodal refractory periods. This study highlights its potential usefulness in pediatric patients.

    Area of Science:

    • Pediatric Cardiology
    • Clinical Electrophysiology
    • Pharmacology

    Background:

    • Disopyramide is an established antiarrhythmic medication.
    • Congenital heart disease can lead to complex arrhythmias in children.
    • Electrophysiologic effects of disopyramide in pediatric populations require further elucidation.

    Purpose of the Study:

    • To investigate the electrophysiologic effects of disopyramide in pediatric patients with congenital heart disease.
    • To assess the impact of disopyramide on cardiac conduction intervals and refractory periods.
    • To compare pediatric findings with adult data.

    Main Methods:

    • Diagnostic cardiac catheterization in 14 children (7 months to 14 years) with congenital heart disease.
    • Administration of a single intravenous dose of disopyramide (2 mg/Kg).
    • Surface EKG, intra-atrial, His bundle electrograms, and atrial pacing with extrastimulus technique before and after drug administration.

    Main Results:

    • Significant prolongation of the HV interval, atrial, and AV nodal refractory periods observed.
    • Most consistent effect was the prolongation of atrial refractory periods.
    • Electrophysiologic effects showed variability, potentially linked to vagal tone.

    Conclusions:

    • Disopyramide demonstrates significant electrophysiologic effects on the cardiac conduction system in pediatric patients.
    • Findings in children resemble adult responses, particularly those with cholinergic blockade.
    • Direct depressant effects on atrial and AV nodal tissue suggest potential therapeutic utility of disopyramide in pediatric arrhythmias.

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