Improved identification of acute coronary syndromes with second generation cardiac troponin I assay: utility of 2-hour delta cTnI > or = +0.02 ng/mL.

Abstract

It has been shown that the 2-h Stratus II delta creatine kinase-MB (CK-MB) is more sensitive and is equally specific compared to a 2-h Stratus II CK-MB and to a 2-h Stratus II delta cardiac troponin-I (DeltacTnI) for identification of acute myocardial infarction and adverse outcome (AO). Because the newest generation of Stratus (Stratus CS) cTnI assay has an analytical sensitivity of 0.03 ng/mL, compared to 0.35 ng/mL for the first generation assay, we undertook a small pilot study of 120 chest pain patients to compare sensitivities and specificities for 30-day AO of the Stratus CS DeltacTnI immunoassay to the DeltaCK-MB and DeltacTnI, as measured by the Abbott Axsym immunoassay, and to the DeltaCK-MB, as measured by the Stratus CS. A Stratus CS DeltacTnI > or = +0.02 ng/mL in 2 h was more sensitive (61.9%) than an Axsym DeltaCK-MB > or = +1.3 ng/mL (38.1%; p = 0.03), a Stratus CS DeltaCK-MB > or = +0.4 ng/mL (38.1%; p = 0.03), and an Axsym DeltacTnI > or = +0.3 ng/mL (33.3%; p = 0.03) for 30-day AO. There were no differences in specificities. Our data support enhanced identification of ACS with a second generation cTnI assay. Pending larger studies, patients with a rise in DeltacTnI of > or = +0.02 ng/mL in 2 h, as measured by the Stratus CS immunoassay, should receive consideration for aggressive anti-ischemic therapy and further diagnostic testing prior to making an exclusionary diagnosis of non-ischemic chest pain.

• Authors: Francis M Fesmire, Connie E Fesmire
• Journal: The Journal of emergency medicine (J Emerg Med) Vol. 22 Issue 2 Pg. 147-52 (Feb 2002) ISSN: 0736-4679 [Print] United States
• PMID: 11858918 (Publication Type: Comparative Study, Evaluation Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Isoenzymes
• Troponin I
• Creatine Kinase
• Creatine Kinase, MB Form

Topics

• Adult
• Aged
• Biomarkers (blood)
• Creatine Kinase (blood)
• Creatine Kinase, MB Form
• Female
• Humans
• Isoenzymes (blood)
• Male
• Middle Aged
• Myocardial Infarction (blood, diagnosis)
• Pilot Projects
• Prospective Studies
• ROC Curve
• Sensitivity and Specificity
• Time Factors
• Troponin I (blood)