Clinical implications of a recent adjustment to the high-sensitivity cardiac troponin T assay: Some results

Letter to the Editor. Recently, some concerns have been reported about a technical bulletin by Roche Diagnostics GmbH (Mannheim, Germany) regarding the adjustment to the calibration curve of the Elecsys Troponin T high-sensitivity (hs) assay [1]. According to the bulletin, the goal of the manufacturer was to recalibrate the control materials of the Troponin T hs assays to return to the original assay specifications. The revised lots of calibrators (lots 167345 and 167650) should yield measurable cardiac troponin T (cTnT) concentrations in a greater proportion of patient samples for which the concentrations were undetectable with previous lots, including lot 163704 [1]. This adjustment regarding calibration materials may have major implication for patient care, including the recalculation of the 99th percentile value for cTnT assay [1], which is the cornerstone of the definition of myocardial infarction [2]. The aim of the present report is to compare the results obtained by measuring several plasma samples of healthy subjects and patients with acute or chronic cardiac diseases to give the users of Elecsys Troponin T hs assay some information on the difference in cTnT values measured using the previous and the new recalibrated lots.