Cardiac troponin I level correlates with chronic-phase left ventricular function after successful direct percutaneous transluminal coronary angioplasty in patients with acute myocardial infarction.

OBJECTIVES: The relationships between cardiac troponin I, various biochemical markers, and chronic-phase left ventricular ejection fraction (LVEF) after successful direct percutaneous transluminal coronary angioplasty (PTCA) were examined in 36 patients with acute myocardial infarction. METHODS: Biochemical markers were measured on admission, immediately after, and from 6 hours to 9 days after PTCA. RESULTS: The time to peak values were: creatine kinase-MB 9.7 hours, cardiac troponin I 9.8 hours, myoglobin 10.7 hours, creatine kinase 10.6 hours, cardiac troponin T 18.6 hours, and myosin light chain 68.9 hours. Cardiac troponin T, cardiac troponin I and myosin light chain levels were elevated over 9 days after successful direct PTCA. Chronic-phase LVEF inversely correlated with peak values of creatine kinase-MB (r = -0.519, p < 0.01), cardiac troponin T (r = -0.500, p < 0.01), cardiac troponin I (r = -0.441, p < 0.05) and creatine kinase (r = -0.411, p < 0.05). The values of cardiac troponin I, cardiac troponin T, creatine kinase and creatine kinase-MB at each sampling point were significantly inversely related to chronic-phase LVEF. The value of cardiac troponin I at each time point for 7 days correlated well with chronic-phase LVEF. CONCLUSIONS: Cardiac troponin I has high specificity for predicting long-term cardiac function after successful direct PTCA when early values are unavailable.