Implementation of a High-Sensitivity Cardiac Troponin Assay and Diagnostic Protocol for Suspected Acute Coronary Syndrome.

We assessed if implementation of a high-sensitivity cardiac troponin I (hs-cTnI) assay and 0/2-hour diagnostic protocol for evaluation of suspected acute coronary syndromes was associated with improved resource utilization by retrospectively studying adult emergency department (ED) encounters for chest pain/discomfort at 21 hospitals in an integrated health system. The hs-cTnI assay (Beckman Access) and corresponding 0/2-hour protocol were introduced on November 16, 2022. The preimplementation period was January 1, 2018 to June 30, 2019 (prior to the COVID-19 pandemic) and the postimplementation period was January 1, 2023 to June 30, 2024. Co-primary outcomes were ED disposition and 30-day coronary testing, assessed following adjustment for confounders and within strata of predicted risk. There were 87,647 preimplementation and 97,677 postimplementation encounters with similar demographics (median age 59 years, 55.2% vs 55.5% female) and risk factors (diabetes 26.6% vs 25.8%; chronic kidney disease 13.5% vs 13.6%; coronary revascularization 12.3% vs 10.6%). Adjusted prepost analyses revealed an increase in ED discharges (75.0% vs 78.9%, adjusted difference +3.9%, 95% CI +3.4% to +4.4%) and a decrease in 30-day coronary testing (36.2% vs 24.1%, adjusted difference-12.1%, 95% CI -12.9% to --11.4%). Notably, results differed by predicted risk strata, with decreased ED discharges and increased 30-day coronary testing among nonlow risk encounters. In conclusion, hs-cTnI assay and protocol implementation was associated with decreased overall resource utilization among ED patients with chest pain, despite increased utilization among nonlow risk encounters. Structured use of hs-cTn assays can improve alignment between risk and resource allocation in this population.