RESUMO
The aim of this study was to evaluate QT dispersion in acute and sub-acute stages of myocardial infarction and clarify the relationship between QT dispersion and myocardial viability. We studied 95 patients with acute myocardial infarction. The QT dispersion values were compared to those of a control group of 50 healthy subjects. In the patients with acute myocardial infarction dispersion of ventricular repolarization was evaluated on the standard electrocardiograms obtained at the time of admission and ten days later. Two-dimensional echocardiography examination was performed to assess and compare left ventricular wall motion at different stages. QT dispersion values were increased in patients with acute myocardial infarction and levels were higher in the early than in late phases. A better recovery of QT dispersion was found in those patients who demonstrated improvement of left ventricular contractility. The modifications of QT dispersion can reflect the alterations of myocardial contractility.