Early kinetic profiles of troponin I and T measured by high-sensitivity assays in patients with myocardial infarction

Publication date: Available online 12 February 2020Source: Clinica Chimica ActaAuthor(s): John W Pickering, Joanna M Young, Peter M George, Christopher J Pemberton, Antony Watson, Sally J Aldous, Toby Verryt, Richard W Troughton, A Mark Richards, Fred S Apple, Martin P ThanAbstractThe early concentration kinetic profiles of cardiac troponin in patients with non-ST-elevated myocardial infarction (NSTEMI) measured by high-sensitivity cardiac troponin I (hs-cTnI) and T (hs-cTnT) assays have not been described.In intermediate-to-high-risk of NSTEMI patients we measured serial cTn concentrations on ED arrival, at 1, 2, 3, 6-12, 24 and 48-hours with hs-cTnI and hs-cTnT assays. Log-normal curves were fitted to concentrations from time from symptom onset, and the time to rule-out decision thresholds estimated (hs-cTnI: 2ng/L and 5ng/L; hs-cTnT: 5ng/L).Among 164 patients there were 58 NSTEMI. The hs-cTnI to hs-cTnT ratio increased linearly over the first 6-12 hours following symptom onset. The estimated times from symptom onset to the 2ng/L and 5ng/L thresholds for hs-cTnI were 1.8h (0.1–3.1) and 1.9h (1.1–3.5) hours, and to the 5ng/L threshold for hs-cTnT 1.9h (1.1–3.8). The estimated time to exceed 5ng/L was ≥3 hours in 32.6% (95%CI: 20.0% to 48.1%) cases for hs-cTnI and 33.3% (19.6% to 50.0%) for hs-cTnT.cTnI concentrations increased at a much more rapid rate than cTnT concentrations in patients with NSTEMI. Concentrations of a high proportion of patients took longer than 3...
Source: Clinica Chimica Acta - Category: Laboratory Medicine Source Type: research