There is new evidence that COVID-19 may have a lasting effect on heart health, which may be undetermined in patients who believe they have recovered from the infection.
Two studies from Germany, published Tuesday in the JAMA Cardiology Journal, show how the virus can swirl in the heart for months, even without causing symptoms.
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The first study included 100 coronovirus patients from the University Hospital Frankfurt COVID-19 registry. Most were otherwise healthy adults in their 40s and 50s.
All had an MRI of their heart two to three months later when they had detected the virus, when many had fully recovered. Those images were compared to those who never had COVID-19.
Of those 100 COVID-19 patients, 78 still had visible signs that the virus had an effect on the heart. Sixty of those patients had signs of ongoing inflammation of the heart muscle.
“It’s really hypnotic,” said Dr. Head of Cardiology at the Department of Medicine at Northwestern Medicine in Chicago. Clyde Yancey told NBC News. “This indicates that months after exposure to COVID-19, we can still detect evidence of a heart that is not completely normal.”
The problem may not give rise to physical symptoms, but may indicate a risk for further heart damage.
“Once the heart muscle is hurt, there is a possibility of progressive injury,” Yancy wrote in the editorial accompanying the study.
Because the virus is so new, it is not yet known what the long-term cardiac risks are with COVID-19.
Any pre-existing conditions would not have explained the damage, the study authors said, and only one-third were hospitalized with COVID-19. The rest could stay at home during their illness.
The authors of the study stated, “Our findings may indicate a potential burden of inflammatory disease on a large scale and in growing parts of the population.”
The second study included 39 dead bodies of people who died of COVID-19. Those patients had a tendency to grow up in their 80s. Researchers found evidence of the virus in heart tissue in 24 of 39 patients.
What’s more, in those five patients there were indications that the virus was actually replicating in the heart tissue.
“We know that the virus is making its way into the heart muscle, and causes an inflammatory response, which we have not yet fully understood,” Dr. Matthew Belford, a traditional cardiologist at Wake Forest Baptist Health in Winston-Salem, North Carolina, said. Belford was not involved in the study either.
Doctors have known for some time that COVID-19 can wreak havoc on the circulatory system, potentially leading to potentially dangerous clots. A study published in the journal Cell in March showed that the virus infiltrates the body by binding to a type of receptor on cells called AC2 2.
ACE2 receptors are often found in endothelial cells, which are located in the lining of the heart and blood vessels. One of the main functions of cells is to help regulate blood clots and platelets.
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It is not clear how long such damage will persist.
Yancy said, “Research gets my attention.”
“It makes me say, ‘We’re not done yet,” he said. “We should honor COVID-19.”
“There’s still a lot we don’t know,” he said. “We have to be on guard.”
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