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Effect of pacemaker-induced arrhythmias on coronary blood velocity in conscious man

A Benchimol, K B Desser

    The Journal of Thoracic and Cardiovascular Surgery
    |August 1, 1975
    PubMed

    Insights

    Pacemaker insertion can cause arrhythmias, significantly reducing coronary blood flow velocity. This finding helps explain sudden death during cardiac pacing and competitive rhythms.

    Area of Science:

    • Cardiovascular Physiology
    • Medical Devices

    Background:

    • Pacemaker insertion and pacing can induce arrhythmias.
    • Sudden death is a risk associated with cardiac pacing.

    Purpose of the Study:

    • To measure left coronary blood velocity during pacemaker insertion.
    • To investigate the impact of pacing-induced arrhythmias on coronary blood flow.

    Main Methods:

    • Doppler ultrasonic catheter telemetry system used in 34 conscious subjects.
    • Measurements taken during transvenous pacemaker insertion and right ventricular endocardial pacing.

    Main Results:

    • Ventricular premature depolarizations and tachycardia reduced peak coronary blood velocity by about 50%.
    • Arrhythmias were consequences of catheter manipulation and competitive rhythms.

    Conclusions:

    • Pacing-induced arrhythmias significantly impair left coronary blood flow.
    • Findings offer insights into sudden death mechanisms related to pacemakers and arrhythmias.

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