The CK value is important in the diagnosis of heart attacks. The blood value is also used to identify damage to muscle tissue.
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The creatine kinases (CK) are enzymes that are involved in building up the energy storage for muscle cells. They are found in the body in muscle cells and in the brain.
If muscle tissue is damaged by injuries, overloading, bruising or a lack of oxygen (for example in the event of a heart attack), then creatine kinases emerge from the muscle cells and are then detectable in the blood.
There are four different creatine kinases. These differ only slightly, but only ever occur in a certain body tissue. The CK-MB, for example, belongs to the heart muscle, the CK-MM to the body and skeletal muscles.
The biggest risk factors for heart attack
When is the CK value determined?
Due to the different types of creatine kinase, the CK value is of great diagnostic importance and is used above all when a heart attack and heart muscle diseases are suspected. With the CK value, the doctor can estimate the severity of a heart attack and the damage to the heart muscle quite accurately.
In addition, the CK value is also determined if muscle disorders are suspected. In newborn screening, it serves as an add-on test to rule out congenital muscle loss (muscular dystrophy).
The total CK value and, if necessary, the value of the individual creatine kinases are usually determined in the laboratory. Common abbreviations are CK or CPK (for creatine phosphokinases). The CK value in the blood serum is measured.
Normal range for creatine kinase value
For the total CK, the values for men are below 170 U / l (units per liter = units per liter) in the normal range, for women below 145 U / l. The value of the CK-MB relevant for a heart attack should be less than 25 U / l and less than six percent of the total CK value.
What do CK values mean too high?
A high CK value is always an indication of muscle damage. If the CK value is only slightly above the normal range, this is usually not dangerous. As a rule of thumb, the higher the CK value, the more dangerous the causes of the deviations in the blood picture can be.
Especially when diagnosing a heart attack, doctors can draw conclusions about the damage to the heart muscle from the various CK values:
The overall CK rises about four to twelve hours after the infarction and peaks around 20 hours after the heart attack.
The CK-MB – the special creatine kinase of the heart muscle – shows an increase just three to six hours after the heart attack. From the interpretation of the values, the doctor can estimate the time that has passed since the heart attack and adjust the treatment accordingly.
Basically, when diagnosing a heart attack, the higher the CK value, the more severe the heart attack and the more severely the heart muscle is damaged.
However, a creatine kinase concentration in the blood that deviates from the normal range does not always have to be a sign of a heart attack. A high CK value can also be found muscle diseases and Inflammation of the skin or muscles Clues. Even diseases in which the patient often suffers from cramps (for example Parkinson's disease or epilepsy) cause the CK value to rise.
High CK through sport
There are also some fairly harmless causes for high CK values. After surgery and injections into the muscle, after bumps into the muscles or sore muscles, the CK value can rise. Greatly increased CK values also occur after excessive and unusual muscle training (especially the large muscle groups) in the gym, during bodybuilding or after endurance sports. The values can sometimes rise extremely to two thousand times the normal value.
If this happens only occasionally, the body balances the increased CK concentration itself. However, since creation kinases released into the blood are a "waste" product of the body and must be disposed of via the kidneys, A permanently high CK value also affects the kidneys and can lead to kidney damage.
On the other hand, too low CK values have no medical significance.