Clinical triage concordance of a point-of-care high-sensitivity cardiac troponin I assay using the ESC 0/1-hour algorithm

OBJECTIVE: Although point-of-care (POC) high-sensitivity cardiac troponin I (hs-cTnI) assays have demonstrated good analytical agreement with central laboratory (CL) testing, it remains uncertain whether they yield the same clinical triage decisions. We evaluated the clinical concordance of a POC hs-cTnI assay with a CL assay using the European Society of Cardiology (ESC) 0/1-h algorithm. METHODS: This prospective diagnostic agreement study included 127 patients presenting to the emergency department with suspected acute coronary syndrome. The primary outcome was concordance of patient classification according to the 0/1-h algorithm, assessed using the quadratic weighted kappa (κ) statistic. Secondary outcomes included quantitative agreement assessed by the intraclass correlation coefficient (ICC) and Bland-Altman analysis, and analytical comparability between whole blood and plasma on the POC platform. RESULTS: Overall, 114/127 patients (89.8%) were assigned to the same triage category (κ = 0.921; 95% CI, 0.878-0.964). All 13 discordant classifications (10.2%) occurred between adjacent categories, with no CL rule-in patient classified as POC rule-out. Quantitative agreement between assays was good (ICC = 0.882; 95%CI 0.835-0.917), with a mean bias of -5.27 ng/L. Whole blood and plasma showed close agreement (ICC = 0.999; 95%CI 0.998-0.999), with a mean bias of 0.50 ng/L. CONCLUSIONS: The POC assay showed high clinical concordance with CL-based ESC 0/1-h triage classification, with all discordances confined to adjacent categories. These findings provide pre-implementation evidence supporting further prospective evaluation of POC hs-cTnI testing under routine bedside conditions.