Covid can cause damage to the heart at the cellular level that can lead to lasting problems including irregular heartbeats and heart failure, preliminary research suggests.
The effects of Covid on the heart have been well documented, but a new study focuses on the microscopic changes thought to be caused by the virus.
Researchers at Columbia University in New York examined autopsied heart tissue from people with Covid and found that the infection damaged the way cells in the heart regulate levels of calcium, a mineral that plays an important role in how the organ contracts and pumps blood. through the body. In another part of the study, the same damage was seen in mice with Covid.
The results, presented Monday at the Biophysical Society meeting in San Diego, have not yet been published in a peer-reviewed journal.
When a person is infected with Covid, the immune system launches a strong inflammatory response in an effort to fight off the virus. This inflammation, according to the new study, disrupts the way calcium is stored in the heart.
Calcium ions – a version of the element that carries a positive charge – are important messengers that regulate heart function, including how quickly and forcefully the organ contracts. These ions are stored inside the cells, on deck when the body needs to use them. They are released through channels in the cell membrane, which ensures that the right amount of calcium can get out.
The damage caused by inflammation during a Covid infection seems to keep these channels open, letting too much calcium leak out of heart cells, said Dr. Andrew Marks, cardiologist and professor of biophysics at Columbia University. who co-directed the study. This flood of calcium, he said, can decrease heart function and even cause fatal arrhythmias or irregular heartbeats.
Although inflammation of the heart is a rare but documented side effect of Covid mRNA vaccines, the study only looked at heart tissue from autopsies before the vaccines became available.
“Whatever changes we found were due to the infection,” Marks said, adding that the new study was small and the next step was to take the research to a larger scale.
Calcium also plays an important role in the brain
The findings built on something Marks and his team had observed earlier in the pandemic when investigating how Covid affects another organ: the brain.
In a study published in 2021 in the journal Alzheimer’s and Dementia, the team found the same cellular damage to calcium ion channels in autopsied brain tissue from people infected with Covid. These changes, Marks noted, had long been seen in people with Alzheimer’s disease.
Dr. Siddharth Singh, clinical director of the Post-Covid-19 Cardiology Clinic at the Smidt Heart Institute at Cedars-Sinai Medical Center in Los Angeles, said the latest findings help explain the heart and brain problems seen in Covid patients. .
“Calcium is an essential mineral for life,” said Singh, who was not involved in the research.
“It can put things together for the heart and the brain.”
Viral infections causing inflammation of the heart are not a new finding.
“Before Covid came into the picture, during the winter when virus infections were skyrocketing, we were seeing more people presenting with things like myocarditis,” Singh said, referring to the inflammation of the cardiac mucosa.
He said the damage was not necessarily permanent. “Over time, symptoms like brain fog and palpitations get better in some patients, so to some extent that damage looks like it can heal,” he said, adding that patients need to be studied longer. for researchers to understand exactly what factors allow this to happen.
Dr Nicholas Hendren, a cardiologist at UT Southwestern Medical Center in Dallas, said: “Once this is better understood, we may be able to develop therapies to address this damage and potentially therapy to protect the heart and cardiovascular system. Covid damage.” Hendren was also not involved in the new research.
Can vaccines protect against Covid heart damage?
Another new study, published in the Journal of the American College of Cardiology on Monday, suggests vaccination may protect against major cardiovascular events — like heart attacks and strokes — associated with Covid.
The study analyzed data from nearly 2 million people in the National Covid Cohort Collaborative database. About 218,000 had received at least one dose of the Pfizer-BioNTech or Moderna mRNA vaccine, or Johnson & Johnson’s single-dose vaccine. Even partial vaccination was associated with a lower risk of cardiovascular events for at least six months, the researchers found.
More research is needed to confirm whether Covid vaccination reduces the risk of these cardiovascular events, but the new study begins to expand understanding of the unknown long-term effects that vaccines can have on the heart.
“There have been a lot of different messages about the effectiveness of vaccines,” said study co-author Joy Jiang, MD/Ph.D. candidate at the Icahn School of Medicine at Mount Sinai in New York. “It pushes the narrative to encourage people to get vaccinated because of this associated benefit.”
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