Defining the analytical characteristics of a novel high-sensitivity point-of-care troponin I assay in its intended clinical environment
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James Hatherley
Abstract
Objectives
To assess the imprecision and stability of the point-of-care troponin I assay in the Emergency Department and its correlation and bias to two central laboratory troponin I assays (Siemens Atellica and Abbott Alinity).
Methods
Imprecision and stability testing was performed on opportunistically selected samples using whole blood in the emergency department by non-laboratory trained personnel. Assay comparisons were undertaken on samples taken from participants of the Mersey Acute Coronary syndrome Rule Out Study.
Results
The coefficient of variation (95 % confidence interval), at the 99th percentile for the point-of-care assay, was 8.1 % (6.1–12.1 %) but with a wide confidence interval reflective of considerable scatter at values just below the 99th percentile. The 10 % limit of quantification was 7.5 ng/L (1.7–61.8 ng/L). All samples met the ≤2 ng/L stability criteria for a duration of 4 h and under. The point-of-care assay very strongly correlated and had a negative bias with the Siemens Atellica and Abbott Alinity assays, Pearson’s R=0.99 and 0.95, mean difference −29.7 ng/L and −13.3 ng/L respectively.
Conclusions
The Siemens VTLi point-of-care assay fulfils high-sensitivity criteria when operated by non-laboratory trained staff using whole blood in its intended environment. Lithium heparin samples are likely stable up to 4 h. Significant bias between the point-of-care and two central laboratory assays negates the use of these assays interchangeably.
Funding source: Abbott Diagnostics
Funding source: Quidelortho
Funding source: Liverpool University Hospitals NHS Foundation Trust
Funding source: Siemens Healthineers
Funding source: northwest coast academic science network
Acknowledgments
The staff of the Emergency Departments within Liverpool University Hospitals NHS Foundation Trust. The staff within Liverpool Clinical Laboratories.
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Research ethics: MACROS-2 received approval from the Health Research Authority and local Research Ethics Committee (REC reference 21/EM/0202). The study is consistent with the declaration of Helsinki. All patients were consented with specific use of additional venous whole blood for the investigational VTLi POC assay and storage for subsequent analysis of CL hs-cTnI assays.
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Informed consent: All patients gave informed written consent after receiving a patient information leaflet regarding the study.
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Author contributions: AK is the senior author and was involved in conceptualization, manuscript editing and is chief investigator of MACROS-2. POC was involved in conceptualization, manuscript editing and statistical analysis for imprecision data. GM was involved in manuscript editing and data collection. SD contributed to manuscript writing/editing and statistical analysis. JH contributed to conceptualization, was the lead for manuscript writing and editing and also undertook the majority of the statistical analysis. All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: Dr A Khand has been a Speaker or expert member and has received fees from the following companies: Bayer, Daiichi Sankyo, Astra Zeneca, Menarini, St Jude, Abbot Vascular, Abbott Diagnostics. Dr A Khand has received research funds from the following companies: Bayer medical, Menarini, Dragons Den awards (Liverpool University hospitals). Dr A Khand holds research contracts with Abbott Diagnostics. Dr A Khand is the director for Northwest Educational Cardiac Group (nwecg), a not for profit medical educational group and has received sponsorship for educational courses from Bayer, Astra Zeneca, Genzyme (Sanofi), Daiichi Sankyo, Circle Cardiovascular, Menarini, Circle. Dr A Khand works with the Northwest coast Innovation agency in England, is a clinical Champion for high sensitive troponins with funds awarded (both personal payment for work and transformation funding) for dissemination of accelerated diagnostic pathways. P.O. Collinson, Associate Editor of The Journal of Applied Laboratory Medicine, ADLM; received honoraria for lectures from Siemens Healthineers; on the advisory board of Psyros Diagnostics and Radiometer and has previously advised Siemens Healthineers and LumiraDx; consultant to IFCC Committee on Clinical Applications of Cardiac Bio-Markers (C-CB) (unpaid). Please note Siemens Healthineers previewed the manuscript but all decision making and intellectual property resides with the authors.
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Research funding: Funding for the Mersey Acute Coronary syndrome Rule Out Study-2, which this manuscript is a sub-study of: Siemens Healthcare Diagnostics Limited, Faraday House, Sir Williams Square, Frimley, Camberley, Surrey GU16 8QD. Amount: £40000. Quidel Cardiovascular Inc., San Diego, CA 91121, USA. Amount: £205000. Charitable funds of St. Georges Hospital Biochemistry Department, London, UK. Amount: £10000. Abbott Diagnostics, Lake Forest, USA. Amount £50000 (Financial assistance) and £60000 (Sample analysis). Menarini UK, Menarini House, Mercury Park, Wycombe Lane, Wooburn Green, Buckinghamshire, HP10 0HH. Amount: £15000. Liverpool University Hospital NHS Foundation Trust, Longmoor Lane, Liverpool, L9 7AL. Amount: £60000. Innovation agency, North-West Coast, NHS England, Vanguard House, Keckwith Lane, WA4 4AB. Amount: £47962. Liverpool University Hospital Charitable funding: £30000. Cartridges and devices provided FOC by Siemens.
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Data availability: The data that support the findings of this study are available on request from the corresponding author, AK. The data are not publicly available due to privacy/ethical/legal/commercial restrictions.
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Supplementary Material
This article contains supplementary material (https://doi.org/10.1515/cclm-2025-0374).
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