National Academy of Clinical Biochemistry and IFCC Committee for Standardization of Markers of Cardiac Damage Laboratory Medicine Practice Guidelines: Analytical Issues for Biochemical Markers of Acute Coronary Syndromes

### a. Background In 1999, the National Academy of Clinical Biochemistry (NACB)1 published the first standards of laboratory practice addressing analytical and clinical recommendations for use of cardiac markers in coronary artery diseases (1). The objectives were to recommend the appropriate implementation and utilization of cardiac biomarkers, specifically for cardiac troponin (cTn), which had just gained US Food and Drug Administration (FDA) clearance as a cardiac biomarker to aid in the diagnosis of acute myocardial infarction (AMI). In 2001, the IFCC Committee on Standardization of Markers of Cardiac Damage (C-SMCD) recommended quality specifications for analytical and preanalytical factors for cTn assays (2). The objectives were intended for use by the manufacturers of commercial assays and by clinical laboratories that use cTn assays. The overall goal was to establish uniform criteria so that all cTn assays could objectively be evaluated for their analytical qualities and clinical performance. These general principles can also be applied to creatine kinase MB (CK-MB) mass and myoglobin assays by use of the analytical recommendations in this document. In this report, we provide the background for establishing updated practice guidelines with recommendations addressing analytical issues for cardiac biomarkers based on 8 years of evidence-based medical and scientific observations since the publication of the initial recommendations (1). ### recommendations: analytical aspects of acs biomarkers ALL CLASS I 1. Reference decision-limits should be established for each cardiac biomarker based on a population of normal, healthy individuals without a known history of heart disease (reference population). For cardiac troponin …