QT interval dispersion - Non-invasive marker of ischemic injury in patients with unstable angina pectoris?

Prognostic assessment of unstable angina pectoris is a common clinical prob lem for physicians. Markers of myocardial cell injury, serial electrocardio graphic findings and ST segment monitoring are mainly studied for prognosis . We investigated the relation between myocardial injury and the value of car diac troponin T and QT interval dispersion in hospitalized unstable angina patients. This is a prospective study that includes adult patients admitted to an eme rgency department with Braunwald class IIIB unstable angina pectoris. Eight y-six patients were enrolled in the study (mean age of 57 +/- 12 years, 63 males and 23 females). Cardiac troponin T was assayed and QT dispersion cal culated from surface ECG. Fifty-eight patients with troponin T < 0.1 ng / m / and 28 patients with troponin T levels <greater than or equal to> 0.1 for med group 1 and group 2, respectively. There were no significant differences in sex, age, history of coronary reva scularization or ECG findings such as ST depression and T inversions betwee n the two groups. The QT dispersion was significantly greater in patients w ith elevated cardiac troponin T levels (77 +/- 18 msec vs 38 +/- 12 msec; p < 0.014). Because QT interval dispersion exhibited an association with cardiac tropon in T levels, it may be used as a non-invasive marker of ischemic injury in patients with unstable angina.