COVID-19 can kill heart muscle cells, preventing shortening

Since early in pandemic, COVID-19 has been linked to heart problems, including reduced ability to pump blood and abnormal heart rhythms. But it has been an open question whether it is these viruses that are causing the heart-borne virus, or an infectious response to a viral infection elsewhere in the body. Such details have an impact on understanding how best to treat coronavirus diseases that affect the heart.

A new study from the University of Washington School of Medicine in St. Louis provides evidence that COVID-19 patients’ heart damage is caused by the virus attacking and reproducing within heart muscle cells, leading to cell death and affecting shortening of heart muscles. The researchers used stem cells to devise a heart-shaped contraction that modulates the human disease and may help in the study of the disease and develop possible therapies.

The study is published February 26 in the Journal of the American College of Geology: Basic to Translational Science.

“Early in the pandemic, we had evidence that this coronavirus can cause heart failure or heart injury in healthy individuals in general, which was frightening to the cardiology community,” said lead author Kory J. Lavine, MD , PhD, associate professor of medicine. “Even some college athletes who were ousted to return to competitive athletics after COVID-19 infection showed scarring in the heart. There has been debate as to whether this is due to a direct infection. heart or as a result of a systemic systemic response that occurs due to lung infection.

“Our study is unique because it conclusively shows that, in patients with COVID-19 who have developed heart failure, the virus affects the heart, particularly heart muscle cells.”

Lavine and his colleagues – including colleagues Michael S. Diamond, MD, PhD, Professor of Medicine Herbert S. Gasser, and Michael J. Greenberg, PhD, assistant professor of biochemistry and molecular biology – gas cells for tissue engineering that model how human heart rate contraction contracts. Examining these models of cardiac tension, they concluded that viral disease not only kills heart muscle cells but destroys the muscle fiber units responsible for heart muscle contraction.

They also showed that this cell death and loss of heart muscle fiber can occur even without inflammation.

“Inflammation can be a second blow as well as damage caused by the virus, but the inflammation itself is not the first cause of the heart injury,” said Lavine.

Other viral infections have long been linked to heart damage, but Lavine said SARS-CoV-2, the virus that causes COVID-19, is unique in its effect on the heart. heart, especially in the immune cells that respond to the disease. In COVID-19, immune cells called macrophages, monocytes and dendritic cells control the immune response. For most other viruses that affect the heart, T cells and B cells of the immune system are on the horizon.

“COVID-19 triggers a different immune response in the heart compared to other viruses, and we don’t know what that means yet,” Lavine said. “In general, the immune cells seen respond. other viruses tend to be associated with relatively short-term infection that resolves with supportive care. But the immune cells we see in COVID-19 heart patients tend to be associated with a persistent condition that can have long-term effects. These are societies, so we need more research to understand what is happening. “

Part of the reason why these questions on the cause of heart damage has been difficult to answer is the difficulty of studying heart tension from COVID-19 patients. The researchers were able to confirm their results by examining print from four COVID-19 patients who had heart-related heart injuries, but more research is needed.

To that end, Lavine and Diamond, are working to develop a mouse model of the heart injury. To emphasize the speed of the operation, Lavine noted the severity of the heart damage that COVID-19 can cause.

“Even young people with mild symptoms can later develop heart problems that limit their ability to exercise,” said Lavine. “We want to understand what ‘s happening so we can prevent it. put on or handle. In the meantime, we want everyone to take this virus seriously and do their best to take steps and stop the spread of the disease, so that the pandemic becomes even worse. of preventable heart disease in the future. “

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This work was supported by funding from the National Institutes of Health (NIH), grant numbers R01HL141086, R01 HL138466, R01 HL139714, 75N93019C00062 and R01 AI127828; Burroughs Welcome Fund, donation number 1014782; Defense Advanced Research Project Group, grant number HR001117S0019; March of Dimes Foundation, donation number FY18-BOC-430198; The Foundation for Barnes-Jewish Hospital, grant number 8038-88; and Washington University Children’s Trace Institute and St. Louis Children’s Hospital. Louis, grant numbers CH-II-2017-628 and PM-LI-2019-829. Images were produced at the University of Washington Center for Cellular Imaging (WUCCI), which is part-funded by the University of Washington Children’s Trace Institute and St. Louis Children’s Hospital. Louis, CDI-CORE-2015-505 and CDI-CORE-2019 -813 grant numbers; and The Foundation for Barnes-Jewish Hospital, grant number 3770. The authors thank Dr. Cynthia Goldsmith for assistance in interpreting electron micrographs and the McDonnell Genome Institute (MGI) at the University of Washington School of Medicine for assistance. by performing series and analysis.

Bailey AL, et al. SARS-CoV-2 affects human engineered heartbeat and modulates COVID-19 myocarditis. Journal of the American College of Geology: Basic to Translational Science. February 26, 2021.

The 1,500 faculty physicians of the University of Washington School of Medicine are also medical staff at Barnes-Jewish and St. Louis Children’s hospitals. Louis. The School of Medicine is a leader in medical research, teaching and patient care, ranking among the top 10 medical schools in the country by US News & World Report. Through its links with Barnes-Jewish and St. Louis Children’s Hospitals, the School of Medicine is affiliated with BJC HealthCare.