Clinical Significance of Exercise-Induced T Wave Normalization in Patients With Q-Wave Myocardial Infarction: Comparision With Myocardial Perfusion Scintigraphy

In clinical practice, determination of viable myocardium in infarcted area is important for subsequent management and prognosis. The aim of the study was to evaluate the relationship between T-wave normalisation during exercise testing and detection of viable tissue in infarcted area by Thallium-201 re-injection study. Study group included 75 patients (71 M,4 F, mean age 55+/-10) with myocardial infarction that was diagnosed 2-7 months before exercise testing. Thallium-201 stress re-injection myocardial perfusion scintigraphy (SPECT) was performed in all patients. The study group was divided into two subgroups according to the presence or absence of transient T-wave normalisation associated with Q-wave leads corresponding to the infarcted area. During exercise testing, T-wave normalisation was observed in 45 patients in at least two contiguous leads (group 1). T-wave normalisation was not observed in the remaining 30 patients (group 2). The prevalence of viable tissue in infarcted area was higher in group 1 than group 2 (66% vs. 30%; p<0.001). The sensitivity, specificity, and accuracy of T-wave normalisation for detection of viable tissue were 76%, 56%, and 64%, respectively. In conclusion, T-wave normalisation during exercise testing is associated with higher prevalence of viable tissue in infarcted area compared to patients with persistent wave inversion.