Evaluation of QT, QT dispersion, and T-wave peak to end time changes after primary percutaneous coronary intervention in patients presenting with acute ST-elevation myocardial infarction.

BACKGROUND Acute ST-elevation myocardial infarction (STEMI) is associated with significant arrhythmia and cardiac arrest. QT prolongation can occur in the setting of ischemia or acute STEMI as a risk factor for arrhythmia. The goal of this study was to investigate corrected QT interval (QTc), QT dispersion (QTd), and T-wave peak to end (TPE) times in this patient population and evaluate the effect of primary percutaneous coronary intervention (PCI) in STEMI patients on these indices. METHODS This study was a clinical trial, whereby eligible patients presenting with acute STEMI who were appropriate candidates for primary PCI were enrolled. QTc, QTd, and TPE indices were calculated before and after the procedure. RESULTS Eighty patients (60 male, 20 female) with a mean age of 58.8 years were evaluated. We found significant reduction in QTd after PCI (mean, 5.8 ms before PCI vs 3.6 ms after PCI; P<.001) and significant reduction in TPE after PCI (mean, 9.7 ms before PCI vs 7 ms after PCI; P<.001). QTc did not show significant changes before or after PCI (44.9 vs 43.7; P=.057). CONCLUSION Our study showed that primary PCI was effective in reducing the degree of arrhythmogenic indices such as QTd and TPE. Our findings suggest that ischemia-induced QTd and TPE are important arrhythmogenic parameters responding to successful primary PCI and may be used as markers for successful repercussion.