Diagnosing myocardial injury in an acute chest pain cohort; long-term prognostic implications of cardiac troponin T and I

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Original Article: https://doi.org/10.1093/clinchem/hvae110

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Webinar (on demand), available through October 31, 2025: https://www.myadlm.org/education/all-webinars/webinars/2024/october/diagnosing-myocardial-injury-in-an-acute-chest-pain-cohort/on-demand

Abstract

Background

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).

Methods

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.

Results

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.

Conclusions

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.