Performance of risk stratification for acute coronary syndrome with two-hour sensitive troponin assay results

Abstract

Background: Risk stratification processes for patients with possible acute coronary syndrome (ACS) recommend the use of serial sensitive troponin testing over at least 6h. Troponin assays vary in their analytical performance. Utility in accurate risk stratification at 2h post-presentation is unknown.

Methods: A diagnostic accuracy study of patients presenting to the emergency department (ED) with symptoms of ACS was performed. Troponin was measured at 0, 2 and 6h post-presentation. Acute myocardial infarction (AMI) was adjudicated by cardiologists and incorporated the 0 and 6h troponin values measured by a sensitive troponin assay. Results were described using standard measures of test accuracy.

Results: Of the 685 patients, 51 (7.4%) had 30-day AMI or cardiac death, and 76 (11.1%) had secondary outcomes (all cause death, ACS and revascularisation procedures). There was no significant difference in the diagnostic accuracy of early versus late biomarker strategies when used with the current risk stratification processes. Incorporation of a significant delta did not improve the stratification at 2h post-presentation.

Conclusions: Accelerated risk stratification of patients with ACS symptoms may occur at 2h post-presentation using troponin results measured by a sensitive assay. Incorporation of such a strategy could support improvements in patient flow within EDs.

Keywords: Acute coronary syndrome; Emergency Service; Hospital; Risk stratification; Troponin.