Creatine Phosphokinase-MB is a sensitive and specific indicator to diagnose the Acute Myocardial Infarction. CPK-MB measures the blood level and relatively bounds the combination of the 2 variants such as isoenzymes CKM and CKB in enzyme phosphocreatine kinase. Measuring ratio of the CK-MB1 and CK-MB2 isoforms is quite easier and accurate. Creatine Phosphokinase-MB test detects isoforms of B subunit of the myocardium. Creatine Phosphokinase-MB is useful as the best diagnostic tools for the MI even elevated after the irreversible myocardial injury occurred. It is easier to identify the patient with the acute coronary syndrome along with the therapeutic intervention of any mitigates myocardial damages.