Serial troponin I measurements detect recurrent myocardial infarction after initial acute myocardial infarction

Serial serum troponin I and CK-MB measurements were obtained for 36 patients presenting to the emergency department with a confirmed diagnosis of acute myocardial infarction (AMI). For each patient, the normalized percentage of maximum troponin I concentration (%max TropI) was plotted vs. the time from the maximum value to obtain a kinetic decay plot. The linear correlation plots of the--Log (%max TropI) vs. time were compared. Patients with uncomplicated AMI (n = 31) showed linear correlation coefficients (CC) above 0.97 (mean CC = 0.991). Patients with AMI complicated by recurrent myocardial infarction (n = 5) documented by corroborate clinical findings, electrocardiographic abnormalities and/or abnormal CK-MB results showed linear correlation coefficients (CC) less than 0.97 (mean CC = 0.763). Using a cutoff value of CC = 0.97, both patient groups were completely separated and re-infarction or extension of infarction was predicted with 100% accuracy, sensitivity and specificity.

Kinetic modeling of troponin I decay in patients with AMI correctly differentiates patients with complicated vs. non-complicated courses.