Cardiac troponin I (cTnI) is a standard biomarker for the diagnosis of acute myocardial infarction (AMI). While older, ultra-sensitive cTnI (us-cTnI) assays use the 99th percentile as the reference threshold, newer high-sensitive cTnI (hs-cTnI) assays use the limit of detection or functional sensitivity instead. However, little has been done to systematically compare these two methods. The present study also served as a validation of hs-cTnI in our laboratory. Here, we compared the results obtained from the blood serum obtained from 8810 patients using the us-cTnI and the hs-cTnI assays run in tandem on the ADVIA Centaur XP analyser. We found that in 2279 samples the concentration of cTnI measured with the ultra-sensitive method was below the detection limit, while with the high-sensitive method, only 540 were below the detection limit. We also compared results from these assays with the ultimate diagnosis of a subset of individuals. The analysis of the results below cut-off with the ultra-sensitive method showed that this method would not detect 96 cases related to heart disorder. Overall, the main finding of our research is that hs-cTnI is the preferable option and is able to be deployed effectively in the laboratory setting.
Keywords: Acute coronary syndrome; Myocardial infarction; Troponin I; Verification; acute coronary syndrome, ACS; acute myocardial infarction, AMI; cardiac troponin I, cTnI; chronic obstructive pulmonary disease, COPD; coefficient of variation, CV; confidence interval, CI; functional sensitivity, LoQ; high-sensitive cTnI, hs-cTnI; limit of blank, LoB; limit of detection, LoD; ultra-sensitive cTnI, us-cTnI; upper reference of normal, URL.
© 2022 The Authors. Published by Elsevier B.V.