Introduction
Blood values in the case of heart muscle inflammation give the doctor a chance to assess the processes in the body. The heart as an inner organ cannot be looked at directly, but only indirectly checked for its condition. A combination of certain laboratory parameters, however, gives an indication or a very strong clue as to which disease in the body is the underlying cause. A definite diagnosis cannot be guaranteed on the basis of blood values alone, but the probability of a correct diagnosis can be increased more and more by combining blood values with other examination methods.
Can you have heart muscle inflammation if your blood counts are normal?
A heart muscle inflammation despite normal values is definitely possible, although very unlikely. Here, as so often, a principle of medicine applies that can be applied almost everywhere: There is nothing that does not exist. As already described, some increases in blood values only occur with a certain time delay, whereas some can only be measured in pathological concentrations within a relatively short time window.
What blood values indicate heart muscle inflammation?
As can already be seen from the term heart muscle inflammation, in order to make a reliable diagnosis one needs blood values that reflect both the inflammation and the affected organ in the body, i.e. the heart. The most heart-specific blood value currently available for diagnosis is troponin I. This protein is normally found in the blood in virtually no form, so that an increased occurrence in the patient’s blood always requires clarification.
However, troponin is not detectable in the blood until 3-6 hours after damage to the heart muscle cells, which is why blood is always drawn twice with an interval of at least four hours if heart disease is suspected. The two most striking values to detect the inflammation are the leukocyte count and the value of the C reactive protein (CRP for short). The leukocyte count is part of every small blood count and, if increased, provides a very strong indication of inflammation.
The determination of the CRP, on the other hand, is not part of the small blood count, but is considered a very meaningful value, the level of which already allows conclusions to be drawn about the cause of the inflammation or infection. However, in order to be able to make an estimation based on the leukocyte count as to what could be the cause of the heart muscle inflammation, the various components of the leukocytes must be determined, for which a separate blood test is also required. Troponins are another protein from muscle cells, whereby the isoforms Troponin I and Troponin T are specific to heart muscle.
Three to six hours after damage to heart muscle cells, an increase in troponins in the blood is detectable, although the maximum concentration is only reached after about four days. Troponin I and T are considered to be the most specific markers of heart muscle damage and are determined several times during the course of a cardiac problem in order to be able to estimate the course of the concentration. Furthermore, the level of troponin concentration correlates with the patient’s disease prognosis.
The C-reactive protein (CRP) is a protein synthesized by the body and produced by the liver. It has been scientifically established that during an inflammation, the CRP level increases after about 6 hours. However, the exact relationship between inflammation and increased production has not yet been clarified.
However, almost every inflammation is accompanied by an increase in CRP, so that this value is very reliable, but cannot give any information about the localization of the inflammation. In bacterial infections, the increase in CRP is much higher than in viral infections. The normal value is below 1mg/dL.
Creatine kinase is a protein that occurs in all body muscles and is released into the bloodstream when these muscle cells are damaged. Three different forms of creatine kinase are known today, of which the heart muscle-specific CK-MB can be determined individually. However, the total mass of creatine kinase can also be determined in the blood and is primarily regarded as an indicator of damage to muscle tissue.
Which tissue is affected can only be determined with the help of an exact determination of the different forms of creatine kinase. The creatine kinase MB (CK- MB) is a subgroup of the creatine kinases. Relatively speaking, the proportion of CK-MB is highest in the heart muscle, so that only when heart muscle tissue is damaged is it released into the blood, resulting in a detectable increase.This value is therefore relatively heart-specific and is included as standard in the diagnosis of heart muscle damage.
Lactate dehydrogenase is an enzyme that is found in almost all body cells and plays a role in the energy production process from sugars. An elevated LDH value stands for increased cell death in the body. However, it is not possible to locate the point of cell death using the enzyme.
The normal range for lactate dehydrogenase is between 260 and 500 units per liter, i.e. units per liter of blood plasma. Glutamate oxaloacetate transaminase is another protein found in certain body cells, namely in liver cells as well as in heart and skeletal muscle cells. An increase in the GOT value or the ASAT value (ASAT is used synonymously with GOT) is therefore not a specific indication of heart muscle inflammation, but can be an indication to examine further heart specific blood values.
The so-called white blood cells are typically elevated in all types of inflammation. Depending on the cause of the inflammation, different white blood cell fractions are elevated. While bacterially induced heart muscle inflammation (myocarditis) causes an increase in granulocytes, viruses cause an increase in lymphocytes. The normal range for white blood cells is between 4000 and 10,000 per mm3 or μl.
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