Performance of the High-STEACS Early Rule-Out Pathway for High Sensitivity Cardiac Troponin T at 30-days in a US population

Abstract

Abstract Background The High-STEACS Early Rule-Out Pathway for High Sensitivity Cardiac Troponin T (hs-cTnT) is an algorithm designed to rule-out myocardial infarction (MI) in ED patients with symptoms concerning for acute coronary syndrome (ACS). High-STEACS was validated in the United Kingdom but has yet to be evaluated in the US. Purpose The objective of this secondary analysis of the STOP-CP (High Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification) United States (US) multicenter study is to determine the performance of the High-STEACS hs-cTnT Pathway in a multisite US cohort. Methods Patients (≥ 21 years old) presenting to the (ED) with symptoms suggestive of ACS were enrolled (1/25/2017-9/6/2018) at 8 US medical centers. Participants with 0- and 1-hour hs-cTnT measures were stratified into outpatient and admission dispositions using the established High-STEACS hs-cTnT cut-points. Cardiac death or MI and major adverse cardiovascular events (MACE; a composite of cardiac death, MI, and coronary revascularization) at 30-days were adjudicated. Negative and positive predictive values (NPV and PPV) and negative and positive likelihood ratios (-LR and +LR) for the High-STEACS pathway were calculated for each outcome with 95% confidence intervals. Results Overall, 1430 patients were studied. 54.2% (775/1430) were male with a mean age of 57.6 ± 12.8 years. At 30-days, 12.8% (183/1430) of patients experienced cardiac death or MI and 14.2% (203/1430) had MACE. High-STEACS classified 59.9% (857/1430) to the outpatient disposition and 40.1% (573/1430) to admission. Among patients stratified to the outpatient group, 1.9% (16/857) experienced cardiac death or MI and 3.4% (29/857) had MACE at 30-days. The NPV and -LR for High-STEACS were 98.1% (95%CI 97.0-98.9) and 0.13 (95%CI 0.08-0.21) for 30-day cardiac death or MI and 96.6% (95%CI 95.2-97.7) and 0.21 (95%CI 0.15-0.30) for 30-day MACE. For patients stratified to admission, 29.1% (167/573) had 30-day cardiac death or MI and 30.4% (174/573) had MACE. This yielded a PPV and +LR for 30-day cardiac death or MI of 29.1% (95%CI 25.5-33.1) and 2.8 (95%CI 2.6-3.1) and 30.4% (95%CI 26.6-34.3) and 2.6 (95%CI 2.4-2.9) for 30-day MACE. Conclusions The High-STEACS hs-cTnT Pathway stratified nearly 60% of patients to an outpatient disposition, but these patients had high rates of 30-day cardiac events. These findings suggest that providers should be cautious before using this pathway among US patients with possible ACS.