Higher-than-normal CPK-1 levels:

Because CPK-1 is found mostly in the brain and lungs, injury to either of these areas can increase CPK-1 levels. Increased CPK-1 levels may be due to:

• Brain cancer
• Brain injury (due to injury, stroke, or bleeding in the brain)
• Electroconvulsive therapy
• Pulmonary infarction
• Seizure

Higher-than-normal CPK-2 levels:

CPK-2 levels rise 3 - 6 hours after a heart attack. If there is no further heart muscle damage, the level peaks at 12 - 24 hours and returns to normal 12 - 48 hours after tissue death.

Increased CPK-2 levels may also be due to:

• Electrical injuries
• Heart defibrillation (purposeful shocking of the heart by medical personnel)
• Heart injury (for instance, from a car accident)
• Inflammation of the heart muscle usually due to a virus (myocarditis)
• Open heart surgery

CPK-2 levels do NOT usually rise with chest pain caused by angina, pulmonary embolism (blood clot in the lung), or congestive heart failure.

Higher-than-normal CPK-3 levels are usually a sign of muscle injury or muscle stress and may be due to:

• Crush injuries
• Muscle damage due to drugs or being immobile for a long time (rhabdomyolysis)
• Muscular dystrophy
• Myositis (skeletal muscle inflammation)
• Receiving many intramuscular injections
• Recent nerve and muscle function testing (electromyography)
• Recent seizures
• Recent surgery
• Strenuous exercise