Diagnostics for suspected myocarditis
Every medical diagnosis begins with the medical history. Here, the above-mentioned symptoms are asked for, and importance is also attached to a possible trigger of the disease (cold, flu-like infection). Afterwards, the physical examination is in the foreground.
Here, special attention is paid to water retention. These can be detected in the legs as well as possibly in the lungs. Cardiac arrhythmia can be diagnosed by listening to the heart.
Heart murmurs occur particularly in the tensing phase of the heart, the so-called systole. If the pericardium is also affected by the inflammation, a so-called pericardial rubbing (rubbing the two leaves of the pericardium against each other) can be heard. A further diagnostic step is the ECG.
Cardiac arrhythmias are most easily detected here, and a possible localization of the heart problem can also be performed. As a rule, a blood sample is also examined in the laboratory. Here, attention is paid to heart-specific enzymes.
However, we also look for viruses or bacteria that may have caused the problem. Furthermore, imaging (X-ray, heart ultrasound, heart MRI) can be groundbreaking. For final diagnosis, a biopsy is taken from the heart muscle.
The changes that become apparent in the ECG in the case of myocarditis are as varied as the symptoms with which the disease makes itself felt. If a cardiac arrhythmia is present, it is particularly easy to detect in the ECG. It can manifest itself in the form of a simple tachycardia (heartbeat too fast).
But also a so-called arrhythmia can indicate a rhythm disturbance. This causes additional tension in the ventricles between the normal heartbeats.In the ECG, the electrical currents of the heart are conducted at different positions. This makes it possible to visualize and localize disturbances in the excitation conduction and/or regression very well.
Similar to a myocardial infarction, a so-called ST segment depression or T-wave negation can also occur. These also indicate a disturbed excitation conduction. If a part of the heart is no longer reached by the electrical excitation at all, this is called a thigh block.
A left bundle branch block therefore means that the left ventricle no longer receives electrical signals and is therefore uncoordinated and no longer contracts. During myocarditis, various values in the blood are changed. On the one hand, these include indicators that point to heart damage, and on the other hand laboratory tests often reveal the triggers for the disease.
Cardiac enzymes are among the blood values specific to the heart. These are released into the bloodstream when heart cells are damaged. These are the CK, the CK-MB and the troponin-T.
In addition to these rather unspecific heart markers, BNP may also be elevated, which may indicate the onset of heart failure. If a viral infection is a possible trigger, it is worthwhile to perform a virus serology, since the pathogen is often found in the blood. If heart muscle inflammation is suspected, X-rays and cardiac ultrasound are the imaging methods of choice.
Both can be performed quickly and can provide initial indications of myocarditis. If the suspicion of myocarditis is confirmed by the examinations, an MRI (magnetic resonance imaging) of the heart should be performed. The entire image is composed of many individual images taken at different levels. Thus, with modern technology, even a virtual three-dimensional reconstruction of the heart is possible. With the help of the MRI images, myocarditis can be diagnosed, and the course of the disease can also be monitored by means of multiple images.
