The hs-cTnI assay demonstrated high analytical concordance (94.5%) with contemporary cTnI, yielding fewer false negatives (up to 1.0%) but more false positives (up to 6.7%) for ACS diagnosis.
Observational (n=1,096)
Does the hs-cTnI assay improve analytical and diagnostic performance compared to contemporary cTnI assays for diagnosing Acute Coronary Syndrome?
Implementing hs-cTnI assays requires rigorous analytical and clinical verification, as they reduce false negatives but may increase false positives compared to contemporary assays.
OBJECTIVES: High sensitivity cardiac troponin T and I (hs-cTnT and hs-cTnI) assays show analytical, diagnostic and prognostic improvement over contemporary sensitive cTn assays. However, given the importance of troponin in the diagnosis of myocardial infarction, implementing this test requires rigorous analytical and clinical verification across the total testing pathway. This was the aim of this study. DESIGN AND METHODS: =1096) was verified using 99th percentiles for both genders (cTnI: 30 ng/L, hs-cTnI: 25 ng/L) and for men and women separately (hs-cTnI: M: 34;F: 16 ng/L). Discordant data was correlated with clinical and laboratory information. Diagnosis of Acute Coronary Syndrome (ACS) or Non-ACS was adjudicated by two cardiologists independently. RESULTS: The hs-cTnI assay showed a lower (10-fold) critical outlier rate (0.091%) and more detectable results above the limit of detection (LOD) (23.4%) and 99th percentile (2.4%), compared to cTnI. Analytical concordance between the two assays was high (94.5%) but decreased (91.7%) when gender-specific hs-cTnI cut-offs were used. The hs-cTnI assay gave fewer false negatives (up to 1.0%) but disproportionately more false positives (up to 6.7%) overall, which improved (3.9%) for serial measurements. CONCLUSIONS: Laboratories should analytically and clinically verify hs-cTn assays before use, with attention to performance and the clinical and diagnostic algorithms that support appropriate testing and result interpretation. Work in the pre- and post-analytical phases is necessary to augment the analytical improvement in the new era of troponin testing.
Lee et al. (Thu,) conducted a observational in Acute Coronary Syndrome (n=1,096). High sensitivity cardiac troponin I (hs-cTnI) assay vs. Contemporary sensitive cTnI assay was evaluated on Analytical concordance and diagnostic accuracy for Acute Coronary Syndrome. The hs-cTnI assay demonstrated high analytical concordance (94.5%) with contemporary cTnI, yielding fewer false negatives (up to 1.0%) but more false positives (up to 6.7%) for ACS diagnosis.