Synonyms

   Creatine Kinase-MB

Clinical Significance

   CK-MB was once the primary test requested for people who had persistent chest pain to see if the pain was coming from the heart. It has now been replaced by the troponin test, which is more specific and sensitive.

Specimen

   Serum

Stability

   Refrigerated (preferred) : 7 days

   Frozen : 28 days

   Ambient : 48 hours

Reference Range

   < 25 U/L

Interpretation

   Increased CK-MB concentrations can usually be detected in someone with a heart attack about 4-6 hours after the onset of chest pain. The level of CK-MB peaks approximately at 12-24 hours after the onset of chest pain and then returns to normal within about 48-72 hours.