Early Diagnostic Efficiency of Cardiac Troponin I and Troponin T for Acute Myocardial Infarction

cTn-I, CK-MB, and myoglobin are significantly more specific for AMI than are CK and cTn-T. Myoglobin is the biochemical marker having the highest combination of sensitivity, specificity, and negative predictive value for AMI within 2 hours of ED presentation. Neither cTn-I nor cTn-T offers significant advantages over myoglobin and CK-MB in the early (< or = 2 hours) initial screening for AMI. The cardiac troponins are of benefit in identifying AMI > or = 6 hours after presentation.