After an illness with Covid-19, the risk of diseases of the cardiovascular system increases. This was shown, among other things, by a study in »Nature Medicine«. A working group led by Arutha Kulasinghe from the University of Queensland is now presenting an analysis in “Immunology” that explains the mechanism behind it – at least for some of the heart damage observed.
The team examined the heart tissue of seven Covid patients from Brazil and compared it with material from two people who had died of the flu and six people who had neither of the two diseases. They found clear differences between people suffering from corona and those suffering from influenza. “When we examined the heart tissue samples from the influenza patients, we saw that the viruses had caused excessive inflammation,” says the doctor involved in the study, John Fraser: “On the other hand, it was shown that Covid-19 attacks the DNA of the heart, and probably directly and not only as a result of the inflammation.«
Accordingly, Kulasinghe and Co did not find any virus particles in the heart tissue, but instead changed cell tissue that can be attributed to DNA damage and corresponding attempts at repair by the cell. “DNA damage and repair mechanisms promote genetic instability and are associated with chronic diseases such as diabetes, cancer, atherosclerosis and neurodegenerative disorders,” says Kulasinghe.
Previous data on the influence of Covid-19 on the heart was mainly based on biomarkers in the blood of patients and physiological measurements, since the extraction of heart tissue from living people is risky. However, the study is still based on a very small data set, which is why the working group wants to carry out a larger cohort study. In the end, it might be possible to develop initial therapeutic approaches, hope those involved. But one thing already seems certain to them, says Fraser: “We have clearly proven that Covid is not ‘like the flu’.”