The measurement of serum CK-MB isoenzyme is an extremely sensitive and specific indication of myocardial injury. Serum CK-MB levels are helpful to healthcare providers when the total creatine kinase is non-specifically increased, as with intramuscular injections, cardiac catheterization, stroke, etc. Elevations of serum CK-MB occurring in Duchenne’s muscular dystrophy and other neuromuscular disorders can be monitored using this assay.