Major League Baseball Pitcher Eduardo Rodriguez, didn't need an umpire to make the call.
The Red Sox ace dropped out of the 2020 season, because of a diagnosed heart issue, caused by COVID-19.
Now evidence uncovered by researchers here in the Bay Area is shedding new light on how widespread the threat of COVID-related heart damage could be.
"It's very concerning. Even people who have not had severe symptoms we're finding evidence of heart damage," said Dr. Deepak Srivastava, president of San Francisco's Gladstone Institutes.
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In a groundbreaking new study, a Gladstone team used stem cells to create living, beating heart cells, then infected the samples with COVID-19. What they discovered was startling.
"One, this virus can definitely get into the cells. When it gets in it makes a lot more of itself pretty rapidly. And then you start to see a lot of cell death," said investigator Todd McDevitt, Ph.D.
McDevitt and his colleagues were able to image some of that damage. He says the virus' prime targets are long strands of muscle fiber that allow the heart to beat. When they examined the images, they found those same types of muscle strands were essentially chopped into pieces by the virus.
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"And as soon as we saw that, there's no way that a cell that normally, any muscle cell that looks like that is going to be able to beat," explained McDevitt.
And there's potentially more troubling news for athletes and others. When the Gladstone team compared their findings to heart tissue taken from COVID patients who did not survive, they found evidence of the same damage, even in patients who weren't initially diagnosed with heart issues.
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"That was when we felt compelled that we needed to put this out there," said McDevitt.
And the timing could weigh into an increasingly urgent debate. College officials have now revealed evidence of heart inflammation in about a third of Big-10 football players diagnosed with COVID. This comes as President Donald Trump has urged the conference to resume its season.
Dr. Srivastava says the dangers associated with that are becoming more evident.
"The schools and athletes are realizing that they may have not even known they had COVID, been asymptomatic, but when you stress the heart in competitive athletics, then they were starting to see problems in several individuals," he said.
But what isn't clear, is whether that damage could worsen over the years and decades, affecting the lives of even otherwise healthy patients who survive COVID-19.
Still, there is some encouraging news from Gladstone. Researchers say the cardiac cells they're creating could also be critical in testing new heart drugs. The compounds might be added to a COVID treatment to help prevent heart damage at the early stages of infection.
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