Proposals from IFCC Committee on Standardization of Markers of Cardiac Damage (C-SMCD): Recommendations on use of biochemical markers of cardiac damage in acute coronary syndromes

This paper presents evidence and suggestions from the IFCC C-SMCD on the us e of biochemical markers for the triage diagnosis of acute coronary syndrom es. There is general agreement that both 'early' and 'definitive' biochemic al markers are necessary and that these assays must be available with a tur naround time of 1 h or less. Currently, myoglobin is the marker that most e ffectively fits the role as an 'early' marker, whereas 'definitive' markers are cardiac troponins. Since the sensitivity of the initial electrocardiog ram is only 50 % for detecting myocardial infarction, the use of biochemica l markers may significantly contribute to the early diagnosis. New sensitiv e biochemical markers, particularly the cardiac troponins, are presently th e best criterion to detect the presence of small myocardial cell damage. Tw o decision limits are probably needed for the optimum use of troponins: a l ow abnormal value suggesting the presence of myocardial damage and a higher value suggesting the diagnosis of myocardial infarction. Additional studie s should be performed to establish limits for each commercially available a ssay. Finally, it is recognized that there is no need for the use of any bi ochemical marker when the clinical diagnosis is unequivocal, other than for diagnosing reinfarction, estimating the infarct size, and monitoring throm bolytic therapy.