One-hoUr Troponin Using a High-sensitivity Point-Of-Care Assay in Emergency Primary Care (OUT-POC)

Improved Management of Acute Chest Pain in Emergency Primary Care. The OUT-POC Study (One-hoUr Troponin Using a High-sensitivity Point-Of-Care Assay in Emergency Primary Care)

Acute chest pain is a prevalent medical emergency in primary emergency care settings. Triage of chest pain prior to hospital admission presents significant challenges due to the absence of sufficiently sensitive diagnostic tools. Clinical signs, symptoms, risk assessment scores, or a normal electrocardiogram (ECG) can reliably exclude acute myocardial infarction (MI). This diagnostic uncertainty has resulted in chest pain being the second most common cause for acute hospital referrals from Norwegian emergency primary care, even though chest pain is frequently non-cardiac in origin.

In acute MI events, cardiac troponins are released into the bloodstream from the damaged myocardium, where low values are used to exclude MI. Until recently, such testing has necessitated using high-sensitivity cardiac troponin (hs-cTn) assays, which have been limited to hospital laboratories. However, recent technological advancements in point-of-care (POC) testing allow access to whole-blood assays that meet high-sensitivity criteria.

In this upcoming project, the investigators will evaluate the implementation of a whole-blood POC assay (QuidelOrtho TriageTrue hs-cTnI) across six Norwegian emergency primary care clinics. The study plans to enrol 2,500 patients over a period of 1.5 years. The clinical performance of the novel strategy will be investigated, as well as its impact on healthcare utilization and hospital referrals compared to standard care. Additionally, the investigators will assess the prevalence of persistent chest pain and its effects on quality of life, alongside psychological stress and anxiety, through validated questionnaires.

This project aims to offer better and more comprehensive management of the large group of emergency primary care patients with acute chest pain, contributing to reduced hospital referrals, improved quality of life, and more sustainable use of healthcare services.

Study Overview

• Status: Recruiting
• Conditions: Chest Pain; Troponin; Acute Myocardial Infarction (AMI); Primary Care; Point of Care Testing; Acute Coronary Syndromes (ACS); Non-cardiac Chest Pain; Out-of-hours Medical Care
• Intervention / Treatment: Diagnostic test: QuidelOrthos TriageTrue hs-cTnI whole-blood assay

• Study Type: Interventional
• Enrollment (Estimated): 2500
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Tonje R. Johannessen, MD, PhD; Phone Number: +47 95169272; Email: t.r.johannessen@medisin.uio.no
• Study Contact Backup: Name: Odd Martin Vallersnes, Professor; Email: o.m.vallersnes@medisin.uio.no

Study Locations

• Norway
  • Alta, Norway
    • Recruiting
    • Alta Emergency Primary Care Centre
    • Contact: Anne H. Davidsen, MD, PhD student
  • Drammen, Norway
    • Recruiting
    • Drammen Emergency Primary Care Centre
    • Contact: Marthe H. Prytz, MD
  • Fredrikstad, Norway
    • Recruiting
    • Fredrikstad and Hvaler Emergency Primary Care Centre
    • Contact: Simon Andrup, MD, PhD student
  • Oslo, Norway
    • Recruiting
    • Oslo Accident and Emergency Outpatient Clinic
    • Contact: Tonje R. Johannessen, MD, PhD; Email: t.r.johannessen@medisin.uio.no
  • Trondheim, Norway
    • Recruiting
    • Trondheim Intermunicipal Emergency Primary Care Centre
    • Contact: Bjarne Austad, MD, PhD
  • Lyngen
    • Lyngseidet, Lyngen, Norway
      • Recruiting
      • Lyngen Emergency Primary Care Centre
      • Contact: Bent Håkan Lindberg, MD, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients (18+ years) with non-traumatic acute chest pain presenting in emergency primary care
• Troponin testing requested by the treating physician

Exclusion Criteria:

• Acute STEMI (direct hospital referral required)
• Haemodynamically unstable (direct hospital referral required)
• Not able to provide written, informed consent (i.e., due to time restraints, language barriers, impaired cognitive function, or other reasons)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: TriageTrue hs-cTnI 0/1-hour algorithm; Study participants will have a venous blood sample done for hs-cTnI testing using the QuidelOrthos TriageTrue whole-blood POC assay. The treating physician will evaluate the results using an assay-specific 0/1-hour algorithm (developed by Boeddinghaus et al., 2020).	Diagnostic test: QuidelOrthos TriageTrue hs-cTnI whole-blood assay; Already described

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total number of acute myocardial infarctions at the index episode	Proportion of acute myocardial infarction at baseline, to assess the predictive performance of the TriageTrue 0/1-hour algorithm (incl. safety and accuracy) at index	From baseline to 30 days
PROM: Health-related quality of life	Differences in health-related quality of life among chest pain participants will be assessed through self-reported EQ-5D questionnaire with five levels (EQ-5D-5L) incl. the EQ-5D visual analogue scale (EQ VAS).	At baseline and repeated after 90 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Efficiency	The proportion of patients finished triaged as rule-out or rule-in by the protocol at index	Baseline
Total number of hospital referrals at index	Proportion of patients being directly hospitalised at index	Baseline
Total length of stay	Total duration of the chest pain assessment at the clinic at index (i.e., time from arrival to discharge)	Baseline to 24 hours
Composite of acute MI and all-cause death	To assess the prognostic performance of the algorithm after 30, 90, and 365 days	From baseline to 1 year
PROM: Cardiac Anxiety	Changes in cardiac-related anxiety, measured by the Cardiac Anxiety Questionnaire (CAQ)	At baseline and repeated after 90 days
PROM: Depression	Changes in depression, measured by the Patient Health Questionnaire-4 (PHQ-4)	At baseline and repeated after 90 days
PROM: Insomnia	Changes in sleep disturbances, measured by the Sleep Condition Indicator-02	At baseline and repeated after 90 days
PROM: Burden of chest pain	Changes in chest pain frequency, avoidance, intensity and duration, measured by Jonsbu's questionnaire	At baseline and repeated after 90 days
Incremental cost-effectiveness ratio	Difference in quality-adjusted life-years by using the OUT-POC protocol compared to standard care (control)	From baseline to 1 year
Societal costs	Proportion of production loss/sick leave due to chest pain-related diagnoses	From baseline to 1 year
Healthcare utilization	Total number and type of treatment and follow-up in primary and secondary care due to chest pain-related diagnoses	From baseline to 1 year
Healthcare costs	Total costs of assessing patients with chest pain in emergency primary care by using the protocol compared to usual care (control), including unit costs per treatment, visit, stay.	From baseline to 1 year

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Performance of the TriageTrue hs-cTnI whole-blood assay and clinical risk scores	Pre-planned subanalyses to evaluate the performance of various clinical risk scores integrating a single hs-cTnI POC measurement (incl. the History, Electrocardiogram, Age, Risk factors, and Troponin (HEART) score and the Troponin-only Manchester Acute Coronary Symdrome (T-MACS) score).	From baseline to 1 year

Collaborators and Investigators

• Sponsor: University of Oslo
• Collaborators: Vestre Viken Hospital Trust; The Dam Foundation; Oslo University Hospital; Norwegian Health Association; Sørlandet Hospital; Amsterdam UMC; QuidelOrtho

Publications and helpful links

General Publications

• Johannessen TR, Vallersnes OM, Larstorp ACK, Halvorsen S, Atar D. One-Hour Troponin Using a High-Sensitivity Point-of-Care Assay in Emergency Primary Care: The OUT-POC Pilot Study. Cardiology. 2025 Mar 7:1-13. doi: 10.1159/000545127. Online ahead of print.
• Johannessen TR, Vallersnes OM, Larstorp ACK, Halvorsen S, Atar D. Authors' Response Letter - Expanding the Use of Point-of-Care hs-cTnI in Emergency Primary Care: Insights from the OUT-POC Pilot Study. Cardiology. 2025 May 22:1-3. doi: 10.1159/000546344. Online ahead of print. No abstract available.

Helpful Links

• OUT-POC pilot study
• OUT-POC pilot study; Authors' Response Letter

Study record dates

Study Major Dates

• Study Start (Actual): June 27, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: February 20, 2025
• First Submitted That Met QC Criteria: February 26, 2025
• First Posted (Actual): March 3, 2025

Study Record Updates

• Last Update Posted (Actual): December 10, 2025
• Last Update Submitted That Met QC Criteria: December 9, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: chest pain; primary care; acute myocardial infarction; troponin; POC; 0/1-hour algorithm; point-of-care; TriageTrue; hs-cTnI; OOH; out-of-hours; OUT-POC; QuidelOrtho
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Vascular Diseases; Cardiovascular Diseases; Heart Diseases; Myocardial Ischemia; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Acute Coronary Syndrome; Chest Pain
• Other Study ID Numbers: SDAM_FOR555568

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No