High-Sensitivity Cardiac Troponin T-gen6 Assay in Suspected Myocardial Infarction

BACKGROUND: The new high-sensitivity cardiac troponin (hs-cTn) T-generation (gen) 6 assay has higher analytical sensitivity than the current hs-cTnT-gen5 assay, but its clinical performance is unknown. OBJECTIVES: The authors aimed to assess the clinical performance and use-optimized cutoffs of the hs-cTnT-gen6 assay. METHODS: In this secondary analysis of an international, prospective, diagnostic study with central adjudication, patients presenting with suspected myocardial infarction to the emergency department were enrolled. hs-cTnT-gen6 and hs-cTnT -gen5 were measured at the same time points. The analytical and diagnostic performance of hs-cTnT-gen6 were compared to hs-cTnT-gen5, and assay-specific cutoffs for the European Society of Cardiology 0/1- and 0/2-hour algorithms were derived and internally and externally validated. RESULTS: Among 3,346 patients, myocardial infarction was the final diagnosis in 616 (18.4%). The proportion of patients with concentrations above the upper reference limit and therefore having myocardial injury was lower for hs-cTnT-gen6 (35.9%) than for hs-cTnT-gen5 (43.5%; P < 0.001). Diagnostic accuracy at emergency department presentation, expressed as area under the curve, was 0.927 (95% CI: 0.918-0.937) for hs-cTnT-gen6 and 0.931 (95% CI: 0.921-0.94) for hs-cTnT-gen5. A gen6 cutoff of