Multicenter analysis to assess risk of major adverse cardiac events in patients undergoing high‐sensitivity troponin testing in the emergency department

Abstract

Study hypothesisOur objective was to evaluate 30‐day major adverse cardiac events (MACE) in emergency department (ED) patients with normal high‐sensitivity troponins (hs‐trop). We hypothesized that MACE rates would be <1% in patients with (1) two normal troponins regardless of change in troponin (delta) and (2) index hs‐trop below the limit of quantitation (LOQ) regardless of the institution modified HEART score.MethodsThis was a multicenter, retrospective, cohort study of adult patients who presented to 1 of 18 EDs between July 2020 and April 2021 with acute coronary syndrome as defined by an institutional‐modified HEART score completed by their treating physician or midlevel, no evidence of ST‐elevation myocardial infarction, and an index or serial gender‐adjusted hs‐trop within normal limits. The primary outcome was MACE within 30 days of index ED encounter. A detailed case review was then performed for those patients experiencing a MACE.ResultsOf the 9084 patients who had single or serial normal troponins, 31 (0.34%; confidence interval [CI] 0.23%–0.48%) experienced MACE. Of the 6140 patients with 2 normal hs‐trop and a delta (change in troponin) <4, 27 patients (0.44%; CI 0.29%–0.64%) experienced MACE. Only 1 of the 69 patients with 2 normal hs‐trop results but delta (change in troponin) ≥ 4 (1.45%; CI 0.04%–7.81%) suffered MACE. This patient was classified as non‐low risk by our institutional HEART score. Of 7498 patients with an index hs‐trop <LOQ, 14 (0.19%; CI 0.10%–0.31%) experienced MACE, with 57% (N = 8) deemed non‐low risk by HEART score.ConclusionPatients with 2 normal hs‐trop values in the ED are unlikely to suffer 30‐day MACE. Although it remains unclear whether patients with delta (change in troponin) ≥4 despite normal troponins will have a 30‐day MACE, this situation is rare. Additionally, a single index hs‐trop <6 ng/L demonstrated a low risk for 30‐day MACE independent of the institutional HEART score.