'Medical University Prof. Dr. Paraskev Stoyanov - Varna'
Doi
Abstract
The relationship between QT interval dispersion and dipyridamole-induced, transient myocardial ischemia was assessed in 32 male patients with ischemic heart disease. A standardized, high dose dipyridamole-ECG stress test was used as dipyridamole infusion of 0,56 mg/kg applied i. v. for 4 min followed by 4 min interval of no-dose with E C G and blood pressure monitoring, and in negative test - by a dipyridamole infusion of 0,28mg/kg i. v. for 2 min. Seventeen patients (53%) developed a transient myocardial ischemia with duration of 20 ±7 (4-40) min during the dipyridamole infusion while 15 ones (47%) did not. No regular dynamics and significant differences in the values of total QT interval dispersion and maximum adjacent QT interval dispersion estimated before, during and after the dipyridamole infusion could be established. It was supposed that the severity, duration and time for development of dipyridamole-induced transient myocardial ischemia were not sufficient to generate a dispersion in ventricular repolarization detectable as changes in QT dispersion parameters on surface ECG. The combination of QT dispersion with various non-invasive markers of arrhythmogenic mechanisms could help the estimation of arrhythmogenic risk in the patients with ischemic heart disease
