Very early diagnosis of chest pain by point-of-care testing: comparison of the diagnostic efficiency of a panel of cardiac biomarkers compared with troponin measurement alone in the RATPAC trial
- Paul Collinson1,2,
- Steve Goodacre3,
- David Gaze1,
- Alasdair Gray4 on behalf of the RATPAC Research Team*
- 1Department of Clinical Blood Sciences, St George's Hospital and Medical School, London, UK
- 2Department of Cardiology, St George's Hospital and Medical School, London, UK
- 3School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK
- 4Emergency Department, Royal Infirmary of Edinburgh, Edinburgh, UK
- Correspondence to Dr Paul Collinson, Department of Clinical Blood Sciences, St George's Hospital, Ground Floor, Jenner Wing, London SW17 0QT, UK;
Contributors PC was an investigator on the trial and prepared the paper. SG was the principal investigator. DG arranged and supervised the biochemistry aspects of the study and supervised the point-of-care testing training AG performed the patient data reviews.
- Accepted 22 September 2011
- Published Online First 10 November 2011
Objective To assess the impact of triple marker testing on patient management and the diagnostic efficiencies of different biomarker strategies examined.
Design A prospective randomised trial of triple marker testing by point-of-care testing (POCT); the Randomised Assessment of Panel Assay of Cardiac markers (RATPAC) study.
Setting Six emergency departments.
Patients Low-risk patients presenting with chest pain to diagnostic assessment with a cardiac panel measured by POCT or to diagnosis when biomarker measurement was based on central laboratory testing.
Interventions 1125 patients were randomly assigned to POCT measurement of the triple marker panel of cardiac troponin I (cTnI), myoglobin and the MB isoenzyme of creatine kinase (CK-MB) on admission and 90 min from admission.
Main Outcome Measures Myocardial infarction (MI) was defined by the universal definition of MI. The following diagnostic strategies were compared by receiver operator characteristic (ROC) curve analysis and comparison of area under the curve (AUC): individual marker values, change (Δ) in CK-MB and myoglobin and the combination of presentation or 90 min value plus Δ value.
Results Admission sample measurement of cTnI was the most diagnostically efficient AUC 0.96 (0.93–0.98) with areas under the ROC curve statistically significantly greater than CK-MB 0.85 (0.80–0.90) and myoglobin 0.75 (0.68–0.81). At 90 min cTnI measurement had the highest AUC 0.95 (0.87–1.00) but was statistically significantly different only from Δmyoglobin and ΔCK-MB.
Conclusion Measurement of cTnI alone is sufficient for diagnosis. Measurement of a marker panel does not facilitate diagnosis.
- Acute coronary syndrome
- cardiac troponin I
- contractile proteins
- creatine kinase MB isoenzyme
- delivery of care
- natriuretic peptides
- oxidative stress
- oxidised LDL
- point-of-care testing
- randomised controlled trial
- sensitivity and specificity
- troponin T
Funding The RATPAC trial was funded by the National Institute for Health Research (NIHR) health technology assessment programme (no 06/302/19) and sponsored by the University of Sheffield. The study funders had no role in study design, in the collection, analysis and interpretation of data, in the writing of the report or in the decision to submit the paper for publication. The researchers were independent of the study funders. All authors, external and internal, had full access to all of the data (including statistical reports and tables) in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the NIHR.
Competing interests None.
Ethics approval Ethics approval was obtained from the Leeds East Research Ethics Committee (07/Q1206/22).
Provenance and peer review Not commissioned; externally peer reviewed.