One-Hour Troponin Using a High-Sensitivity Point-of-Care Assay in Emergency Primary Care: The OUT-POC Pilot Study

Novel point-of-care (POC) high-sensitivity cardiac troponin (hs-cTn) tests could enhance acute myocardial infarction (MI) assessment outside hospital. This pilot study evaluates the efficacy, feasibility, and precision of the QuidelOrtho TriageTrue hs-cTnI POC assay when used by non-laboratory personnel in emergency primary care.

A prospective pilot study was conducted from April to June 2024 at the main emergency primary care clinic in Oslo, Norway. Patients ≥18 years with acute nontraumatic chest pain were eligible. The 0/1-h diagnostic algorithms for the POC TriageTrue hs-cTnI and the Roche Elecsys hs-cTnT central laboratory assay (routine protocol) were compared to assess the efficacy and potential safety issues for patients triaged to MI rule-out.

Over 2 months, 199 patients (median age 54 years [interquartile range 45-70]; 52.8% female) were included. Five (2.5%) patients were hospitalised with acute MI. After a single hs-cTnI measurement, the POC algorithm categorised more patients to direct rule-out than the hs-cTnT assay (65% vs. 32%). The rule-out efficacy was similar for both assays after adding the 1-hour measurement (hs-cTnT 74%; POC hs-cTnI 73%). Device-related error rates were low (0.5%), with high reproducibility and repeatability (coefficients of variation < 10%) when performed by non-laboratory personnel.

The 0/1-h algorithm for the TriageTrue hs-cTnI POC assay appears efficient, feasible, and robust when applied by personnel without laboratory expertise in an emergency primary care setting. Further research is warranted, but given the high proportion of single-sample rule-out cases, 1-h measurements could likely be avoided, improving patient management.