Check Your Heart Muscle Health - Creatine Kinase MB (CK-MB) Test

A quantitative test that measures the level of the MB isoenzyme of creatine kinase (CK) in blood serum. CK is an enzyme found in muscles and exists in three isoenzyme forms: MM (skeletal muscle), MB (primarily cardiac muscle), and BB (brain). CK-MB is more specific to the heart than total CK, as it constitutes about 15–30% of total CK in cardiac muscle while accounting for less than 5% in skeletal muscle. Its level in the blood rises 3–6 hours after myocardial injury, peaks within 12–24 hours, and returns to normal within 48–72 hours.