Cardiac troponins in the diagnosis of myocardial contusion.

predictors of adverse cardiac events in more than 600 patients with the acute coronary syndrome. Using receiver-operator curves and a multiple regression model, they concluded that troponin T had a greater sensitivity than troponin I in detecting patients who would eventually have a myocardial infarction and/or die within 30 days. Furthermore, the concern that tropo¬ nin T is inappropriately elevated in patients with renal failure has been clarified and rejected in an abstract by Haller et al.3 They assessed the cardiac troponin T levels in 97 patients with renal failure and classified them into three groups: 22 with coronary artery disease proved by angiography or prior myocardial infarc¬ tion, 40 with two or more recognized risk factors, and 28 with no risk factors. In each, the troponin T value was correlated with cardiac risk; mean±SD values were 0.26±0.08 ng/mL, 0.23±0.06 ng/mL, and 0.07±0.02 ng/mL for the three groups, respectively. Increased troponin T in patients with renal disease was a function of severity of cardiac risk and most likely indicated minimal cardiac injury in this patient population. Another benefit of troponin T that has not been discussed is the low clinical cutoff (0.1 ng/mL) of troponin T assays, allowing detection of even minor infarcts. Cutoffs for troponin I assays vary by manufacturer and are often too high to detect micro-infarcts, and lower cutoffs can result in false positives. According to Ohman et al,4 troponin T has been shown to be an excellent prognostic indicator of adverse cardiac events in patients with unstable angina, due to its analytical sensitivity at very low concentrations. References 1 Brown CS, Bertolet BD. Cardiac troponin: see ya later, CK. We thank Dr. Statland for his comments. We have examined the abstract by Haller et al.1 According to the standardized troponin T test, each group had elevated levels of troponin T. However, according to a new more specific enzyme-linked immunosorbent assay (ELISA), patients with proven coronary' artery disease (CAD) and patients with two or more cardiac risk factors but without CAD had elevated levels. Therefore, in patients with and without CAD and chronic renal failure, cardiac troponin T is unable to distinguish patients with acute myocyte injury, which is the purpose of the test. In the abstract by Ohman et al,2 both cardiac troponins T and I were helpful in stratifying patients with acute coronary syn¬ dromes by risk. In order to make further comments regarding the …