A new study has discovered how the SARS-CoV-2 virus attacks and damages the heart, and answers a long-standing question about mysterious heart conditions after COVID-19 infection. The results could have major implications for the treatment of serious infections and the development of new therapies to prevent long-term damage.
During the pandemic, people with severe COVID-19 infection often showed symptoms of sadness. Those with underlying heart disease are at greater risk for serious illness if they contract it, and reports of abnormal heart rhythms (arrhythmia) in patients with previously healthy patients with acute COVID-19 were common.
Exactly why this is happening, however, has eluded scientists so far. Researchers were not sure if the heart symptoms were due to severe inflammation, as the body responds to the infection, or the virus particles themselves penetrate and attack heart cells.
In the new study, published in the Journal of the American College of Cardiology, scientists finally uncovered the evasive mechanism behind the heart damage of COVID-19 and discovered that the virus penetrates and repeats directly within heart cells, leading to its destruction. The resulting damage impedes the contraction, leading to serious complications and long-term damage.
“Our study is unique because it definitely shows that the virus in patients with COVID-19 who develop heart failure infects the heart, specifically heart muscle cells,” Kory Lavine, senior author and associate professor of medicine, said in a statement.
“Inflammation can be a second hit in addition to damage caused by the virus, but the inflammation itself is not the initial cause of the heart injury.”
The study began with autopsies of COVID-19 patients who showed severe myocarditis (inflammation of heart tissue). Samples from four patients were obtained and analyzed for evidence of SARS-CoV-2 in the heart muscle cells to determine if the virus penetrates these cells. The results proved that virus particles were inside the cells, including evidence of vein protein and the capsule surrounding the viral genome.
Next, the researchers designed human heart tissue using stem cells to model infection and discovered that the virus could penetrate and recur within cardiomyocytes. Even when no inflammation was present, cell death still occurred.
The results are incredibly important to understand how COVID-19 damages the heart, but the methods can have other applications as well. Specifically, engineered cardiac muscle cells may be useful for future COVID-19 research and for creating a new, effective therapy against them.
Until then, the researchers had a powerful message for the people who still needed it.
“Even young people who have had very mild symptoms can later develop heart problems that limit their ability to exercise,” Lavine said.
“We want to understand what is happening so we can prevent or treat it. In the meantime, we want everyone to take this virus seriously and do their best to take precautions and stop the spread so that we do not have another major epidemic of preventable heart disease in the future. ”