Improved early risk stratification and diagnosis of myocardial infarction, using a novel troponin I assay concept

• Published in: European journal of clinical investigation Vol. 35; no. 2; pp. 112 - 116
• Main Authors: Ilva, T., Eriksson, S., Lund, J., Porela, P., Mustonen, H., Pettersson, K., Pulkki, K., Voipio-Pulkki, L.-M.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.02.2005; Blackwell; Blackwell Publishing Ltd
• Subjects: Aged; Area Under Curve; Biological and medical sciences; Cardiology. Vascular system; Coronary heart disease; Diagnosis; Early Diagnosis; Female; General aspects; Heart; Humans; Immunoassay - methods; Immunoassay - standards; Male; Medical sciences; myocardial infarction; Myocardial Infarction - diagnosis; Risk Assessment; Sensitivity and Specificity; triage; troponin; Troponin I - blood; Myocardial infarction; Cardiovascular disease; Risk; Early stage; Myocardial disease; Medicine; Troponin I; troponin; Heart disease; Risk factor; Diagnosis; Stratification; triage
• ISSN: 0014-2972; 1365-2362
• DOI: 10.1111/j.1365-2362.2005.01466.x

Background  We evaluated the clinical performance of a novel cardiac troponin I (cTnI) assay specifically designed to improve the very early risk stratification in acute coronary syndromes. Subjects and methods  Serum and plasma samples (taken 0, 6–12 h and 24 h after admission) from 531 patients with suspected acute coronary syndrome were studied using a novel investigational cTnI assay, reference cTnI assay and myoglobin. The lowest cTnI concentration giving a total assay imprecision of 10% was used as the positive myocardial infarction (MI) cut‐off value. Results  At the time of admission, the investigational assay was positive in 27·9% of the patients, the reference cTnI assay was positive in only 17·5% (P < 0·001) and myoglobin in 24·1% (P = 0·067). Receiver operating characteristic (ROC) curve analysis for the detection of myocardial injury on admission gave area‐under‐curve (AUC) values of 0·937, 0·775 and 0·762, respectively (P < 0·001). Of those MI patients who presented within 3 h of symptom onset, 50·0% were identified by the investigational assay at the time of presentation, compared with 44·2% by myoglobin (P = 0·791) but only 11·5% by the reference assay (P < 0·001). Conclusions  The novel cTnI assay considerably improves the performance of cTnI as an early rule‐in biomarker for MI.