Limited Contribution of Creatine Kinase-Myocardial Band Alongside High-Sensitivity Cardiac Troponin in Diagnosing Acute Myocardial Infarction in an Emergency Department

Cardiac biomarkers are important for assessing individuals with suspected acute myocardial infarction (AMI).European and American guidelines recommend incorporating high-sensitivity cardiac troponin (hs-cTn) assays into rapid rule-in or rule-out protocols for initially assessing patients who potentially have AMI [1,2].Creatine kinase-myocardial band (CK-MB) testing has traditionally been performed in emergency settings and is routinely tested alongside cTn, but lacks tissue specificity, being elevated in various non-cardiac conditions, such as muscle injury, renal insufficiency, and trauma [3].Despite reports of limited clinical utility and cost-effectiveness [4-6], limited data are available regarding the clinical value of CK-MB testing in conjunction with hs-cTn assays, particularly in urban tertiary centers located in regions with high prevalences of chronic kidney disease, heart failure, or ischemic heart disease.In addition, an insufficient number of studies have been conducted to examine the efficacy of CK-MB in emergency departments (EDs) using both hs-cTnT and hs-cTnI assays [3,7].