Fayyad, Rana S.

Most patients with chest pain do not have acute myocardial infarction (AMI), yet post-AMI rule-out disposition remains variable. Detectable but sub-99th percentile high-sensitivity cardiac troponin I (hs-cTnI) provides additional prognostic information. We evaluated the economic value of hs-cTnI-guided hospitalizations among non-AMI patients. We analyzed 1481 non-AMI chest pain visits with detectable baseline hs-cTnI across 29 U.S. emergency departments (2014–2016) in the prospective HIGH-US trial using the Atellica IM TnIH assay(Siemens Healthcare Diagnostics, Tarrytown, NY, US). We compared observed standard-of-care admissions with modeled pathways incorporating hs-cTnI thresholds and risk scores, assessing admission rates, costs, and diagnostic accuracy for 30-day death/MI. Overall, 1.0% (n = 15/1481) experienced 30-day death/MI. Standard-of-care admitted 59% of patients with 93% sensitivity and 41% specificity. The modeled pathway using hs-cTnI ≥ 5 ng/L plus non-low risk scores was associated with reduced projected admission of 41%, higher specificity of 60%, and the same 93% sensitivity. Estimated per-patient diagnostic costs were lower under Scenario 1 (noninvasive diagnostic testing only; $1025 vs. $1139) and under Scenario 2 (including inpatient/invasive procedures; $2672 vs. $3536). In subgroups, higher hs-cTnI thresholds conferred further economic benefit without compromising sensitivity. Incorporating sub-99th percentile hs-cTnI thresholds alongside risk scores may support more efficient resource use while maintaining safety, although findings require prospective validation.