Laboratory-related issues in the measurement of cardiac troponins with highly sensitive assays

Abstract

A number of assay-related issues can affect the performance of cardiac troponin (cTn) measurement in everyday practice. In this respect, it is vital that all information on cTn assays is known and that the performance characteristics of assays are objectively assessed and adequately described. The advent of the latest generation of more sensitive cTn assays has heralded a new wave of information about low concentrations of cTn in blood. These recent generation assays have improved analytical sensitivity and corresponding performance at low cTn concentrations when compared to their predecessors, providing a convincing goal for laboratory medicine in helping clinicians in the diagnosis of acute myocardial infarction. Crucial to the clinical utility of highly sensitive cTn assays is the laboratorians’ role in closely scrutinizing proposed assays and defining their value in relation to available evidence. Analytical, as well as pre-analytical and post-analytical, aspects must be documented. In this review, we describe what laboratory professionals should know about their cTn assay performance characteristics and the pre-analytical prerequisites for robustness to ensure optimal post-analytical reporting.

Performance evaluation of the high sensitive troponin I assay on the Atellica IM analyser

“…In conclusion, the hs-TnI assay on the Atellica IM analyser demonstrated acceptable imprecision, correlated well with other Siemens Healthcare Diagnostics assays, and had good and predictable STAT TAT with minimal effect on throughput (6,7). Detection capability was consistent with that reported by the manufacturer.…”

“…Current guidelines recommend hs-Tn assays for use with rapid diagnostic algorithms ( 2 - 5 ). Thus, generating results with the fastest time possible is mandatory for the clinical laboratory, especially for STAT analysis ( 6 , 7 ). Ideally, Tn results should be reported within 60 min of when a sample is received, and better yet from when the sample was collected ( 6 ).…”

“…The improved precision of hs-Tn assays at low concentrations allows for shorter time intervals between serial measurements to detect a rising or falling pattern and enables the use of rapid rule-out/rule-in diagnostic strategies (2)(3)(4)(5). For healthcare professionals to effectively implement measurement of Tn with hs-Tn assays, recommendations on the use of hs-Tn assays were published in 2018 by the Academy of the American Association for Clinical Chemistry (AACC) and the The Inernational Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on the Clinical Application of Cardiac Bio-Markers and other experts (6,7). Preanalytical and analytical issues, time to reporting results from either sample receipt or collection (important for rapid algorithms), and other laboratory-related issues were highlighted.…”

“…The goal of this study was to evaluate the analytical performance of the high sensitive troponin I (hs-TnI) assay on the Atellica IM analyser (Siemens Healthcare Diagnostics Inc., Tarrytown, USA) following the recommendations of the AACC/IFCC Task Force and other experts ( 6 , 7 ).…”

Inconsistent Findings of Cardiac Troponin T and I in Clinical Routine Diagnostics: Factors of Influence

“…The patient’s renal function is also unknown; only one creatinine concentration per patient case has been included in the analysis, although a temporal biological variability of cTnT and cTnI is known for chronic renal failure [ 40 ]. It should be emphasized that the cTnT and cTnI measurements were made directly from the fresh blood sample in succession, and there was no storage in between, so pre-analytical problems were minimized [ 41 ].…”