We finally know why COVID-19 damages the heart

A new study has discovered how the SARS-CoV-2 virus attacks and damages the heart, answering a long-standing question about mysterious heart disease following COVID-19 infection. The findings could have big implications for how to effectively treat serious infections and develop new therapies to prevent long-term damage.

Throughout the pandemic, people with severe COVID-19 infection often experienced symptoms of heart distress. People with underlying heart conditions are at a greater risk of serious illness if they catch it, and reports of abnormal heart rhythms (arrhythmias) in previously healthy patients with acute COVID-19 have been common .

However, the exact reason why this is happening has eluded scientists until now. Researchers are unsure whether heart symptoms are the result of severe inflammation when the body responds to infection, or whether the viral particles themselves invade and attack heart cells.

In the new study, published in the Journal of the American College of Cardiology, scientists have finally unveiled the elusive mechanism behind heart damage from COVID-19, finding that the virus enters and replicates directly in heart cells, leading to their destruction. The resulting damage interferes with the contraction, leading to serious complications and long-term damage.

“Our study is unique because it definitely shows that in patients with COVID-19 who have developed heart failure, the virus infects the heart, especially heart muscle cells,” said Kory Lavine, lead author and professor. associate of medicine, in a press release.

“Inflammation can be a second hit in addition to the damage caused by the virus, but the inflammation itself is not the initial cause of the heart damage.”

The study began with autopsies of patients with COVID-19 who had severe myocarditis (inflammation of the heart tissue). Samples from four patients were taken and analyzed for the presence of SARS-CoV-2 in heart muscle cells, to determine if the virus enters these cells. The results showed that viral particles were in the cells, including evidence of the spike protein and the capsule that surrounds the viral genome.

Subsequently, the researchers designed human heart tissue using stem cells to model the infection, finding that the virus could enter and replicate in cardiomyocytes. Even in the absence of inflammation, cell death has occurred.

The results are extremely important for understanding how COVID-19 damages the heart, but the methods may have other applications as well. Specifically, the modified heart muscle cells could be useful for future research on COVID-19 and create a new therapy effective against it.

Until then, researchers had a powerful message for people who still need to hear it.

“Even young people who have very mild symptoms can develop heart problems later on that limit their ability to exercise,” Lavine said.

“We want to understand what is happening so that we can prevent it or deal with 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 don’t have an even bigger epidemic of preventable heart disease in the future.