Objective

Guidelines recommend high-sensitivity cardiac troponin to risk stratify patients with possible myocardial infarction and identify those eligible for discharge. The aim was to evaluate adoption of this approach in practice and to determine whether effectiveness and safety varies by age, sex, ethnicity, or socioeconomic deprivation status.

Setting

Adult acute hospitals in England

Design

A multi-centre cohort study was conducted in 13 hospitals across the United Kingdom.

Participants

137,881 consecutive admissions between November 2021 and October 2022.

Methods

Routinely collected data including high-sensitivity cardiac troponin I or T measurements were linked to outcomes. The primary effectiveness and safety outcomes were the proportion discharged from the Emergency Department, and the proportion dead or with a subsequent myocardial infarction at 30 days, respectively. Patients were stratified using peak troponin concentration as low (<5 ng/L), intermediate (5 ng/L to sex-specific 99th percentile), or high-risk (>sex-specific 99th percentile).

Results

Half of all patients with possible myocardial infarction were identified as low-risk by high-sensitivity cardiac troponin. These patients were very low risk, with just 1 in 1000 experiencing an index myocardial infarction and 1 in 3000 having a subsequent myocardial infarction at 30 days following discharge. Despite this only two-thirds of these patients were discharged with substantial variation by age, deprivation, ethnicity, and site.

Conclusions

The findings identify important opportunities to improve care for patients with possible myocardial infarction and prevent unnecessary hospital admission through the consistent application of risk stratification with high-sensitivity cardiac troponin in practice.