Inflammation of the heart muscle, known as 'inflammatory cardiomyopathy' or 'myocarditis', is one of the most common causes of sudden death in young adults. They can however also gradually lead to life-threatening heart failure. In recent years, the disease has been increasingly reported in the media because it occurs in people who have had a Covid infection or, in very rare cases, who have been vaccinated against the virus.
Heart muscle inflammation is often detected too late. The main reason: the symptoms are initially unspecific and not always severe and the suspicion can only be confirmed by relatively complex imaging techniques such as magnetic resonance imaging (MRI). To make a reliable diagnosis, tissue has to be taken directly from the heart muscle. Extensive tests are usually required to check whether the therapy is working or not, and these tests can expose patients to high levels of radiation. This makes it difficult to examine patients regularly and without complications in order to improve treatment quickly and individually. This can also lead to further progression of the disease and irreversible necrosis of the heart tissue.
Well-known procedure for a new field of application
Cardiologist and DZHK scientist PD Dr. med. Bettina Heidecker and her team at the German Heart Centre at the Charité in Berlin have discovered a method that has been around for decades and could help solve the problem: magnetic resonance imaging (MRI).
The procedure is based on the physical principle that streams of ions (e.g. sodium, calcium, potassium) in the heart create a magnetic field. The direction and strength of this field is called the vector.
If an inflammation of the myocardium alters this current of ions and thus the vector only minimally, doctors could easily make a diagnosis using the harmless technique of MRI. On the one hand, it could be possible to determine whether a patient has a heart muscle inflammation. On the other hand, it could also be used to check whether a therapy is working - this is the simplified assumption of Dr. Heidecker and her team. The MRI scan has no side effects, as it only measures the heart's magnetic field. It only takes a few minutes and no electrodes must be attached.
Early results show: Magnetocardiography provides very accurate diagnosis
A total of 233 patients (with and without definite suspicion of heart muscle inflammation) underwent magnetocardiography. The results were published in the Journal of the American Heart Association: the researchers were able to determine with a high degree of accuracy whether a heart muscle inflammation was present - especially in the case of an acute heart muscle inflammation. In addition, they were able to use MRI to show how successful an immunosuppressive therapy (to combat the body's excessive, inflammatory reactions) was - after just one week or even earlier, as opposed to the one month required by echocardiography.
However, there is still a long way to go before MRI can be used in clinical practice, says Bettina Heidecker. The benefits of the method need to be proven much more reliably. Bettina Heidecker and her team are therefore planning a prospective study to compare the diagnostic accuracy of MRI with that of myocardial biopsy. They are also planning to perform systematic MRI examinations in patients with chest pain after a viral infection or vaccination. "Magnetocardiography can neither replace established diagnostic imaging nor myocardial biopsy," says Dr Heidecker. "But it could help us to use these relatively complex and sometimes stressful methods in a much more targeted way, so that we can better treat a very serious disease in the future.
Patients who are interested in participating in the further study can contact the following e-mail address: kardio-cbf-agh(at)charite.de.
Source: press release DHZC
