Corona can lead to a blockage of the blood vessels – with fatal outcomes. A study now shows why some people are particularly at risk.
Corona is picking up speed again: the number of infections and hospital stays has been increasing for several weeks. “We estimate that hundreds of thousands of people are currently being treated in hospitals for Corona,” said Maria Van Kerkhove, WHO Corona expert , at the beginning of September. And the number of people infected with corona in need of treatment is likely to continue to rise.
One reason: Covid patients have an increased risk of suffering a stroke or heart attack for up to a year. The group of those at particular risk includes patients with previous illnesses of the cardiovascular system. They experience a disproportionately high rate of blood vessel occlusion during a corona infection.
Researchers at New York University have now been able to decipher why this is the case . In their study published in the journal “Nature Cardiovascular Research”, they explain that the virus can lead to local inflammation in the blood vessels.
Corona “reprograms” immune cells
For their study, they analyzed 27 tissue samples from the arteries of heart patients who had died of Covid. They found the genetic material of SARS-CoV-2 in atherosclerotic plaques – patchy inflammatory deposits that lead to the narrowing of blood vessels. But not just there. The coronavirus had also infected certain immune cells called macrophages called phagocytes.
These infected immune cells were essentially “reprogrammed” by the pathogen: They produce signaling substances – so-called cytokines – which lead to a longer defense reaction by the immune system. The result: There was increased inflammation in the narrowings of the arteries (plaques). These in turn increase the risk of vascular occlusion and thus a heart attack or stroke.
- Rising corona numbers: What you should know if you become infected now
“Our results provide for the first time a direct mechanistic link between Covid-19 infection and the resulting cardiac complications,” said the study’s lead author, Natalia Eberhardt, in a press release.
“The virus creates a highly inflammatory environment that could facilitate the growth and breakdown of plaque and block blood flow to the heart, brain and other major organs.”
Vascular blockages and poorer defense against coronavirus
Based on their observations, the researchers suspect that the body’s immune system has a harder time fighting the coronavirus in people who already have large amounts of plaque in their arteries. This would partly explain why people with arteriosclerosis are more susceptible to Covid-19.The risk of a stroke is also increased with other respiratory infections caused by viruses, such as the flu . However, research now shows that it is seven times higher in Covid patients than in people with influenza .