Sensitivity and long-term prognostic value of cardiac troponin-I increase shortly after percutaneous transluminal coronary angioplasty

Background: After successful coronary interventions, minor elevations of creatine kinase MB (CK-MB) identified a population with a worse long-term prognosis than that in patients without enzyme elevations. In that setting, cardiac troponin-I (cTn-I), a highly specific marker for myocardial injury, was considered for a small study; the results did not support the view that significant myocardial damage occurred during successful percutaneous transluminal coronary angioplasty (PTCA). Hypothesis: The present study was designed to assess the rate of elevated values of cTn-I after successful PTCA and to determine its prognostic value. Methods: CTn-I and CK-MB were measured in 44 patients before and daily for 3 days after PTCA. Two groups of patients were considered according to the presence or absence of elevated levels of cTn-I. The rate of free-event survival was estimated for the two groups using the Kaplan-Meier method and was compared with the log rank test. Results: Globally, 36% of patients had an increase in cTn-I (normal values 0.35 ng/ml) and 9% had an increase in CKMB, p = 0.002. The mean time to maximal enzyme level was 1.8 days for cTn-I and 2.2 days for CK-MB. Over a follow-up of 1375 +/- 416 days, 18% of patients experienced adverse events, and cTn-I did not identify a population of worse longterm prognosis. Conclusion: These results suggest that cTn-I is more sensitive than CK-MB in identifying minor myocardial damage after PICA, but these elevated concentrations of cTn-I in the short-term aftermath of angioplasty do not seem to be a marker of worse long-term prognosis.