Physicians' Academy for Cardiovascular Education

One hs-cTnI measurement can safely rule out MI in early presenters

Troponin in early presenters to rule out myocardial infarction

Literature - Lowry MTH, Doudesis D, Boeddinghaus J, et al. - Eur Heart J. 2023 Jun 23;ehad376 [Online ahead of print]. doi: 10.1093/eurheartj/ehad376


A single measurement of cTn at presentation is a safe and effective method to rule out MI in patients presenting more than 2–3 h after symptom onset [1,2]. However, it is unclear whether a single test strategy is also useful in patients presenting within fewer hours of symptom onset.

Aim of the study

The study aim was to evaluate and externally validate the diagnostic performance of a single cTnI measurement at presentation in patients with suspected MI, stratified according to the time of symptom onset.


This was a secondary analysis of the High-STEACS (High-Sensitivity Troponin in the Evaluation of patients with suspected Acute Coronary Syndrome) trial, a multicenter, stepped-wedge, cluster-randomized controlled trial evaluating the implementation of a hs-cTnI assay in 48,282 consecutive patients with suspected ACS across 10 secondary and tertiary care hospitals in Scotland [3]. In this secondary analysis, 41,103 patients were included, of whom 12,595 (31%) underwent hs-cTnI sampling ≤3 h of symptom onset, 17,468 (42%) within 4–12 h, and 11,040 (27%) >12 h. An adjudicated diagnosis of STEMI was an exclusion criterion.

For external validation, data from 7088 participants of the APACE (Advantageous Predictors of Acute Coronary Syndromes Evaluation) study were used [4,5]. In this prospective, international, multicenter study, patients presenting to the emergency department with symptoms suggestive of MI were included, with the aim of improving the diagnosis of MI.

Thresholds for the limit-of-detection (2 ng/L), rule-out (5 ng/L), and sex-specific 99th centile (16 ng/L in women and 34 ng/L in men) were compared.


The primary endpoint was type I or 4b MI during the index presentation. The secondary endpoint was type I or 4b MI of CV death ≤30 days of the index presentation.

Main results

Rule-out of index MI

MI or CV death within 30 days

External validation


This secondary analysis of the High-STEACS trial showed that a single hs-cTnI measurement below the limit of detection (2 ng/L) enabled the safe rule-out of MI at presentation in patients with suspected MI, also if they underwent testing ≤3 h of symptom onset. In contrast, the widely used 99th centile threshold was not able to rule out MI at presentation, not even in patients presenting >12 h after symptom onset.


Show references

Find this article online at Eur Heart J.

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