The CPK-MB test is a cardiac marker used to assist diagnoses of an acute myocardial infarction. It measures the blood level of CK-MB (creatine kinase-muscle/brain), the bound combination of two variants (isoenzymes CKM and CKB) of the enzyme phosphocreatine kinase.
To distinguish between skeletal muscle and heart muscle damage; sometimes to determine if you have had a heart attack (if the troponin test is not available); sometimes to detect a second or subsequent heart attack or to monitor for additional heart damage.
Normal reference values for serum CK–MB range from 3 to 5% (percentage of total CK) or 5 to 25 IU/L.
