Validation of High sensitivity cardiac troponin (HsTnI) – a breakthrough in diagnostic accuracy of acute coronary syndromes

Abstract

Abstract Introduction/Objective Cardiac troponin (cTn) testing is an essential component of the diagnostic workup and management of acute coronary syndromes (ACS). Rapid advances in immunoassay technologies has led to the development of high sensitivity troponin (HsTnl) assays with unprecedented analytic sensitivity and precision. These assays are FDA approved and the use of HsTnl assays is recommended by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), the Joint European Society of Cardiology (ESC), the American College of Cardiology (ACC), and the American Heart Association (AHA) in the Fourth Universal Definition of Myocardial Infarction (2018). The incidence of ACS and its mimics in emergency room visits are much more prevalent in veterans due to increased medical comorbidities. We report here our experience with its validation on two Unicel DXI 800 Access Immunoassays as it has not been well published, particularly in a Veterans Healthcare Clinical Laboratory setting. Methods/Case Report The quality assurance goal of the validation is to demonstrate that the Unicel DXI 800 Access Immunoassay HsTnl assay performs as expected on two analyzers and can be put into clinical use. Method to method correlation with a validated conventional Troponin I, within run precision, day to day precision, and a linearity study were performed as part of this validation. Results (if a Case Study enter NA) For the total of 60 specimens run for the method comparison, Data was plotted and evaluated against EP evaluator, both hsTnI and Troponin I were within the 95% confidence intervals of the method. The linearity study demonstrated results are linear with results as expected. Two levels of cardiac control were tested in a run of 60 replicates each in one day for within run precision, with all results as expected. The day to day precision with three levels of control run daily over 10 days also yielded results as expected. Conclusion The HsTnI is a highly accurate, faster test for the detection of ACS allowing earlier detection of smaller infarcts with much better precision, and there by reducing the morbidity and mortality. It allows rapid discharge of the patients with reducing the cost of hospital stay. This is an example of excellence in laboratory practice by extending the best quality laboratory care with proper validation of instrument methods conducive to laboratory workflow.