Diagnosing Myocardial Injury in an Acute Chest Pain Cohort; Long-Term Prognostic Implications of Cardiac Troponin T and I

• Published in: Clinical chemistry (Baltimore, Md.) Vol. 70; no. 10; pp. 1241 - 1255
• Main Authors: Saeed, Nasir, Steiro, Ole-Thomas, Langørgen, Jørund, Tjora, Hilde L, Bjørneklett, Rune O, Skadberg, Øyvind, Bonarjee, Vernon V S, Mjelva, Øistein R, Norekvål, Tone M, Steinsvik, Trude, Vikenes, Kjell, Omland, Torbjørn, Aakre, Kristin M
• Format: Journal Article
• Language: English
• Published: England 03-10-2024
• ISSN: 0009-9147; 1530-8561; 1530-8561
• DOI: 10.1093/clinchem/hvae110

There are limited data regarding the utility of follow-up cardiac troponin (cTn) measurements after admission for acute chest pain and how long-term stability of myocardial injury and prognostic value differ when using cardiac troponin T (cTnT) or I (cTnI).
We measured high-sensitivity (hs)-cTnT (Roche Diagnostics) and hs-cTnI (Siemens Healthineers) during hospitalization for acute chest pain and after 3 months. Acute myocardial injury was defined as concentrations > sex-specific upper reference limit (URL) during hospitalization and ≤URL at 3-months. Chronic myocardial injury (CMI) was defined as concentrations > URL at both time points. Patients were followed from the 3-month sampling point for a median of 1586 (IQR 1161-1786) days for a primary composite endpoint of all-cause mortality, myocardial infarction (MI), revascularization, and heart failure, and a secondary endpoint of all-cause mortality.
Among 754 patients, 33.8% (hs-cTnT) and 19.2% (hs-cTnI) had myocardial injury during hospitalization. The rate of CMI was 5 times higher by hs-cTnT (20%) assay than hs-cTnI (4%), while acute myocardial injury was equally common; 14% (hs-cTnT) and 15% (hs-cTnI), respectively (6% and 5% when excluding index non-ST-elevation MI (NSTEMI). For hs-cTnT, peak index concentration, 3-month concentration and classification of CMI predicted the primary endpoint; hazard ratios (HRs) 1.38 (95% CI 1.20-1.58), 2.34 (1.70-3.20), and 2.31 (1.30-4.12), respectively. For hs-cTnI, peak index concentration predicted the primary endpoint; HR 1.14 (1.03-1.25). This association was nonsignificant after excluding index NSTEMI.
Acute myocardial injury is equally frequent, whereas CMI is more prevalent using hs-cTnT assay than hs-cTnI. Measuring hs-cTnT 3 months after an acute chest pain episode could assist in further long-term risk assessment. ClinicalTrials.gov Registration Number: NCT02620202.