For these employees, when a holiday falls on a nonworkday -- Saturday or Sunday -- the holiday usually is observed on Monday (if the holiday falls on Sunday) or Friday (if the holiday falls on Saturday).
CK-MB. 1  A creatine kinase-MB (CK-MB) test may be used as a follow-up test to an elevated creatine kinase (CK) in order to determine whether the increase is due to heart damage or skeletal muscle damage.
If this test shows that your CK levels are high, you may have muscle or heart damage. CK is made up of three enzyme forms. These are CK-MB, CK-MM, and CK-BB. CK-MB is the substance that rises if your heart muscle is damaged. CK-MM rises with other muscle damage. CK-BB is found mostly in the brain. Why do I need this test?