O. Doven et al., QT interval dispersion - Non-invasive marker of ischemic injury in patients with unstable angina pectoris?, JPN HEART J, 41(5), 2000, pp. 597-603
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.