Performance of the 0/2‐hour high‐sensitivity cardiac troponin T diagnostic protocol in a multisite United States cohort

Abstract

AbstractBackgroundThe diagnostic performance of the high‐sensitivity troponin T (hs‐cTnT) 0/2‐h algorithm is unclear among U.S. emergency department (ED) patients with acute chest pain.MethodsA preplanned subgroup analysis of the STOP‐CP cohort study was conducted. Participants with 0‐ and 2‐h hs‐cTnT measures prospectively enrolled at eight U.S. EDs from January 2017 to September 2018 were stratified into rule‐out, observation, and rule‐in zones using the hs‐cTnT 0/2‐h algorithm alone and combined with the history, electrocardiogram, age, and risk factor (HEAR) score. The primary outcome was adjudicated 30‐day cardiac death or myocardial infarction (CDMI). The sensitivity and negative predictive value (NPV) of the 0/2‐h rule‐out zone and specificity and positive predictive value (PPV) of the rule‐in zone for 30‐day CDMI were calculated.ResultsOf the 1307 patients accrued, 53.6% (700/1307) were male and 58.6% (762/1307) were White, with a mean ± SD age of 57.5 ± 12.7 years. At 30 days, CDMI occurred in 12.9% (168/1307) of participants. The 0/2‐h algorithm ruled out 61.4% (802/1307) of patients. Among rule‐out patients, 1.9% (15/802) experienced 30‐day CDMI, resulting in a sensitivity of 91.1% (95% confidence interval [CI] 85.7%–94.9%) and NPV of 98.1% (95% CI 96.9%–98.9%). The 0/2‐h algorithm ruled in 12.4% (162/1307) patients of whom 61.7% (100/162) experienced 30‐day CDMI. The rule‐in zone specificity was 94.6% (95% CI 93.1%–95.8%) and PPV was 61.7% (95% CI 53.8%–69.2%) for 30‐day CDMI. The 0/2‐h algorithm combined with HEAR score ruled out 30.7% (401/1307) of patients with a sensitivity and NPV for 30‐day CDMI of 98.2% (95% CI 94.9%–99.6%) and 99.3% (95% CI 97.8%–99.8%), respectively.ConclusionsThe hs‐cTnT 0/2‐h algorithm ruled out most patients. With NPV of <99% for 30‐day CDMI, the hs‐cTnT 0/2‐h algorithm, many emergency physicians may not consider it safe to use for U.S. ED patients. When combined with a low‐risk HEAR score, NPV was >99% for 30‐day CDMI at the cost of reduced efficacy.