Abstract
Diagnostic sensitivity and specificity of clinical and conventional markers prevent or delay treatment and often lead to unnecessary, costly admissions. Millions of patients present annually with chest pain, but only 10%-15% have myocardial infarction. Comparative data are lacking on the new markers, yet using all of them is inappropriate and expensive. The Diagnostic Marker Cooperative Study was a prospective, multicenter, double-blind trial with consecutive enrollment of patients who presented to the emergency department with chest pain. Diagnostic sensitivity and specificity and frequency of increase in patients with unstable angina were determined for creatine kinase-MB (CK-MB) subforms, myoglobin, total CK-MB (activity and mass), and troponin T and I on the basis of frequent serial sampling for ≤24 hours. Of 955 patients with chest pain, 119 (12.5%) had infarction. CK-MB subforms were most sensitive and specific (91% and 89%, respectively) within 6 hours of onset. For late diagnosis, total CK-MB activity was the most sensitive and specific (96% and 98%), followed by troponin I (96% and 93%) and troponin T (87% and 93%). With each marker as the diagnostic standard, CK-MB subforms and myoglobin remained the most sensitive for early diagnosis. ©2001 by Cardiovascular Reviews & Reports, Inc.