When a patient with acute pain in the heart enters the hospital, he is immediately tested for creatine kinase MV (CC MV). A high level of this substance is an early stage marker of myocardial infarction . The study allows you to identify other heart diseases at the initial stage. How to decrypt the analysis results? And what pathologies indicates an increase in QC MV? We will consider these issues in the article.
What it is?
With the breakdown of protein molecules in the human body, creatinine is formed. Under the influence of the creatine kinase enzyme, this substance is converted to creatine phosphate. The biochemical reaction is accompanied by the release of a large amount of energy, which is necessary for muscle work.
The body produces several types of creatine kinase. They are contained in the cells of different muscle groups. Creatine kinase MV is one such enzyme. This substance accumulates in the myocardium and affects the functioning of the heart.
Normally, KK MV is inside the cells. Therefore, the content of this enzyme in the blood of a healthy person is very low. If the cells of the heart muscle are damaged, then there is a sharp release of KK MV into the bloodstream. Most often this is noted with myocardial infarction.
What does the analysis show?
How to find out the level of MV creatine kinase? It is necessary to take a blood test for this enzyme. It is carried out as part of a biochemical study. In the laboratory, the total concentration of all three types of creatine kinase is most often determined, and then the content of the MV fraction is separately calculated. This study allows you to diagnose myocardial infarction at an early stage.
During a heart attack, necrosis of the tissues of the heart muscle occurs. The KK MV enzyme leaves dead myocardial cells and enters the bloodstream. Already 3 hours after the onset of heart pain in the analysis, an elevated level of this substance is determined. The QC MV index becomes maximum 16 to 36 hours after the first signs of a heart attack appear. The amount of enzyme exceeds the permissible norm many times.
The more creatine kinase MV is increased, the more extensive is the damage to the heart muscle. A very high level of the enzyme indicates an extremely serious condition of the patient.
With a heart attack
In most cases, the determination of QC MV is carried out with suspected myocardial infarction. The blood test for the enzyme is repeated several times:
- The first test is done upon admission to the hospital.
- Then the analysis is repeated 3 more times. Blood sampling is made every 3 hours after taking the first sample.
The study helps to track the dynamics of heart attack. The analysis allows to differentiate a heart attack from angina pectoris. If the pain in the heart is not associated with myocardial damage, then the level of the KK MV enzyme remains within the normal range.
At the same time, the patient is given an ECG. Such a comprehensive examination allows you to confirm or deny the presence of necrosis of the heart muscle.
Myocardial infarction is never diagnosed using only one test. It is necessary to trace the level of creatine kinase MB in dynamics. The damage to the heart muscle is indicated by an increase in the content of this substance in the blood.
In the post-infarction period, the study is repeated. This is necessary to monitor the patient's condition. Blood sampling is carried out 3 to 4 days after the attack. If the treatment was effective, then the level of the enzyme is normalized. If the patient still has an increased creatine kinase MV, then this indicates a recurrence of a heart attack.
Other indications
Myocardial infarction is not the only indication for passing an analysis on QC MV. This enzyme can be increased with other heart diseases, as well as with intoxications and injuries. The study is prescribed if the patient has the following symptoms:
- frequent pain in the heart;
- arrhythmia;
- dyspnea;
- cyanosis of the skin;
- swelling of the legs.
Such a clinical picture may be a sign of serious cardiac abnormalities. Also, an analysis is prescribed for bruises of the chest, severe poisoning with alcohol and carbon monoxide, to identify possible myocardial damage.
In children, creatine kinase MV can be increased with complications on the heart after infections. Therefore, a child who has had viral pathologies needs to have a blood test for this enzyme.
Preparation
If myocardial infarction is suspected, the analysis is done urgently after the patient enters the hospital. In this case, there is no time left to prepare for the study.
If the test is carried out as planned, it is better to carefully prepare for the analysis. This will reduce the likelihood of distortion of the sample results.
Analysis is given in the morning on an empty stomach. Venous blood is taken for the study. The rules for preparing for the test are as follows:
- It is necessary to stop drinking alcohol and fatty foods a day before analysis.
- Exclude physical stress before the study.
- Do not smoke 2 hours before blood sampling.
The analysis is not carried out during the course of physiotherapy, as well as if the patient underwent an ultrasound or radiographic examination the day before. The test for the KK MV enzyme is quite sensitive and can give distorted results if the preparation rules are violated.
Norms
The content of creatine kinase MV normally ranges from 0 to 25 units / liter. These reference values are independent of the age and gender of the patient.
In childhood, there is usually a high level of total creatine kinase, that is, all three types of enzyme. This is due to the growth of the child's body. But the normal values of the CF fraction for children are the same as for adults.
Reasons for the increase
A low level of creatine kinase MV in the blood does not indicate any pathology. This substance may even be completely absent from the bloodstream. A zero indicator of the enzyme is considered a variant of the norm.
What diseases are creatine kinase MV elevated for? The cause of an increase in the concentration of the enzyme in the blood may be the following pathologies:
- Myocardial infarction. As already mentioned, in this disease, an enzyme is released into the blood from damaged cells. In the first hours after the onset of the attack, the study can give false negative results. Therefore, the test for QC MV is carried out several times.
- Ray's syndrome. Pathology occurs in children 4-12 years old while taking antipyretic drugs containing salicylic acid (for example, Aspirin). The syndrome is accompanied by encephalopathy and liver failure. In a biochemical blood test in a child, creatine kinase MV and liver enzymes are increased. Children need urgent hospitalization in the intensive care unit.
- Intoxication. In severe poisoning with ethanol and carbon monoxide, the patient may experience myocardial damage. At the same time, the level of the enzyme KK MV exceeds the norm by hundreds of times.
- Injuries. With chest injuries, the heart muscle can be damaged. This is accompanied by an increase in the concentration of KK MV. The higher the level of the enzyme, the more severe myocardial damage.
- Myocarditis. Inflammation of the heart muscle is noted after infections in adults and children. Most often, it occurs as a complication of tonsillitis, flu, diphtheria, herpes. The level of KK MV enzyme is elevated, but not as much as with myocardial infarction
False results
If the patient has an increased creatine kinase MV, then this does not always indicate a pathology. The following factors can distort the analysis results:
- heavy physical activity on the eve of the test;
- taking certain medications;
- the use of fatty foods and alcohol shortly before the test.
In such cases, the analysis is repeated.
If the enzyme is elevated
What if the analysis determines an increased content of creatine kinase MV? Experts do not make an accurate diagnosis of only one blood test per enzyme. If you suspect heart disease, doctors prescribe the following additional tests:
- electrocardiogram;
- echocardiogram;
- Heart MRI;
- blood test for leukocyte formula and rheumatoid factor.
An increase in creatine kinase MV is an alarming signal. After receiving the data of a comprehensive examination, the patient must undergo a course of treatment. You should pay close attention to your lifestyle. It is necessary to completely abandon alcohol and smoking, stop eating fatty and excessively high-calorie foods. An increase in the KK MV enzyme in the blood may indicate severe heart disease. And such pathologies are incompatible with bad habits and malnutrition.
Reviews of specialists and patients
Doctors speak of a blood test for the KK MV enzyme as a very informative study. Previously, with suspected myocardial infarction, patients were bled for CPK (creatine phosphate kinase). However, such a study showed the total content of all types of creatine kinase. And these substances are contained not only in the myocardium, but also in the brain, as well as in the muscles of the skeleton. A high level of CPK did not always indicate myocardial infarction. According to doctors, only an analysis for a cardiospecific enzyme (CF fraction) helps to accurately determine the presence of damage to the heart muscle.
In the video below, you can see the doctor’s opinion about the creatine kinase test.
Not all district hospitals and clinics have a test kit for analysis on QC MV. Such diagnostic equipment is available only in cardiology departments. Therefore, a patient with suspected myocardial infarction should be hospitalized in a hospital specializing in the treatment of heart disease.
Patients also respond positively to a blood test for a cardiospecific enzyme. This study helped them to detect myocarditis at the initial stage, in time to undergo a course of therapy and avoid serious complications. After all, cardiological pathologies very quickly pass into the decompensated stage. A blood test for QC MV helps prevent irreversible changes in the heart muscle.