Abstract
Background: QT dispersion has been shown to be associated with fatal arrhythmias and sudden death in coronary artery disease. A recent study indicated that marked QT dispersion in electrocardiograms (ECGs) obtained during acute ischemia demonstrated a significant correlation with ventricular fibrillation.
Hypothesis: This study investigated the ECG parameters for repolarization (QT dispersion, corrected QT, corrected QT dispersion, and QT dispersion ratio) and their interrelation with acute ischemia.
Methods: QT parameters as well as a newly developed repolarization index, QT dispersion ratio l(QT dispersion/RR interval) × 100] were calculated digitally during rest and ischemia in 32 patients with coronary artery disease (rest angina, Braunwald class III). Results were correlated with clinical consequences, mainly arrhythmias, within a follow‐up period of 5±2days.
Results: While most patients had an increase in all four parameters, only the QT dispersion ratio showed a significant difference when correlated with ventricular arrhythmias (p < 0.001, F ratio = 38).
Conclusion: QT dispersion ratio appears to be a new and promising parameter in predicting ventricular arrhythmias in patients with acute ischemia.
Keywords: QT dispersion, unstable angina, acute ischemia
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