SERUM LEVELS OF CARDIAC TROPONIN-I AND TROPONIN-T IN ESTIMATING MYOCARDIAL INFARCT SIZE SOON AFTER REPERFUSION

Background Cardiac troponin I (TnI) and troponin T (TnT) are highly sp ecific myocardial markers. Objective To determine whether their serum levels can be used to estimate myocardial infarct size soon after repe rfusion. Methods We measured the serum levels of TnI, TnT, and creatin e kinase every 3 h, and the serum cardiac myosin light chain I (MLCI) every 24 h, in 42 patients with acute myocardial infarction in whom re perfusion therapy had successfully been performed. We calculated the s everity of regional hypokinesis by analyzing the follow-up ventriculog rams with the centerline method. Results The time from reperfusion to the peak level for TnI was 6.1 +/- 3.5 h, significantly shorter than t hose for creatine kinase (7.5 +/- 4.1 h) and MLCI (55 +/- 28 h). The t ime to peak level for TnT (6.8 +/- 4.0 h) differed significantly from that for MLCI but not from that for creatine kinase. There was a signi ficant correlation between the peak levels of TnI and TnT (r = 0.86). The peak TnI and TnT levels were correlated well to the peak creatine kinase level (r = 0.67 and 0.69, respectively), total creatine kinase release (r = 0.66 and 0.66), and the peak MLCI level (r = 0.71 and 0.8 0). We observed excellent correlations between the peak levels of TnI and TnT, and regional hypokinesis (r = -0.84 and -0.85, respectively), These were comparable to the correlations between regional hypokinesi s and the peak creatine kinase level (r = -0.75), total creatine kinas e release (r = -0.72), and the peak MLCI level (r = -0.76).Conclusions These results suggest that the peak serum levels of TnI and TnT in pa tients with successful reperfusion are accurate and early indices of i nfarct size. (C) Rapid Science Publishers ISSN 0954-6928.