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Updated: May 5, 2026

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
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The QT interval and cardiac arrhythmias

B Surawicz

    Annual Review of Medicine
    |January 1, 1987
    PubMed

    Insights

    This review examines the link between prolonged QT interval, ventricular arrhythmias, and repolarization dispersion. Current evidence does not support QT interval as an independent predictor for heart disease prognosis.

    Area of Science:

    • Cardiology
    • Electrophysiology

    Background:

    • The QT interval reflects ventricular repolarization, crucial for cardiac electrical stability.
    • Ventricular arrhythmias and dispersion of repolarization are linked to adverse cardiac events.

    Purpose of the Study:

    • To review the relationship between QT interval, ventricular arrhythmias, and repolarization dispersion.
    • To discuss conditions causing prolonged QT interval in clinical practice.

    Main Methods:

    • Literature review of studies investigating QT interval, ventricular arrhythmias, and repolarization.
    • Analysis of clinical conditions associated with prolonged QT interval.

    Main Results:

    • The review explores the complex interplay between QT interval, ventricular arrhythmias, and repolarization dispersion.
    • Various clinical conditions leading to a prolonged QT interval are identified and briefly discussed.

    Conclusions:

    • There is currently no conclusive evidence establishing the QT interval as an independent prognostic marker in patients with coronary or other heart diseases.

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