Markers of myocardial injury in blood following PTCA: A comparison of CKMB, cardiospecific troponin T and troponin I

In 74 patients undergoing elective PTCA, CKMB, cTnT, cTnI-Access (cTnI-Acc) and cTnI-Abbott (cTnI-Abb) were measured in serum before and days 1 and 4 after the procedure. Two of the patients had pronounced biochemical evidence of AMI. In addition, a minor to moderate increase in CKMB, cTnT, cTnI-Acc and cTnI-Abb were found on day 1 in 13, 22, 18 and 25 patients, respectively. Excluding the two with AMI, cTnT was also increased on day 4 in 16 patients and cTnI-Abb in 15 patients, whereas CKMB and cTnI-Acc levels were essentially normal in all. Thus, an unexpected discrepancy between the two methods for cTnI was revealed on day 4. In these 16 patients, there was no statistically significant relationship between the level of cTnT on day 4 and the levers of CKMB or cTnI-Acc on day 1. This is in contrast to a significant correlation to cTnT and cTnI-Abb on day 1. Based on these results, it is speculated that the marker levels on day 1 are due to reversible as well as irreversible damage, whereas cTnT and TnI-Abb on day 4 more selectively reflect the degree of myocardial necrosis. cTnT and cTnI-Abb on day 4 are therefore proposed as valuable markers for further study of the clinical implications of myocardial damage following PTCA and related interventions.