Evidence slowly building for long-term heart problems post-COVID-19
Coronaviruses spread primarily through material released when we breathe, and they cause respiratory symptoms. And SARS-CoV-2, with part of its name coming from "severe acute respiratory syndrome," didn't appear to be an exception. But as time went on, additional symptoms became clear—loss of smell, digestive-tract issues—and these weren't likely to be due to infection of the respiratory tract. And over time, what also became apparent is that the symptoms didn't necessarily fade when the virus was cleared.
As we've studied the virus more, we've learned that the protein it uses to latch on to cells is present in a lot of different tissues in the body, suggesting that a wide variety of different effects could be the direct product of infections of the cells there. This week, the effect that seems to be grabbing attention is heart problems, spurred by a Scientific American article that (among other things) considers the stories of professional and college athletes who have been infected. That was followed by a report that roughly 30 percent of college athletes who've contracted the virus end up with inflammation of the heart muscle, called myocarditis—a number that ESPN is now saying is an accidental exaggeration.
Both reports are heavy on anecdote, but this is not a new thing; ESPN had reported on myocarditis in college athletes back in early August. And, more significantly, the scientific community has been looking into the issue for months. So far, its conclusion is that there are likely to be heart complications, even in patients who had mild COVID-19 symptoms. But the long-term implications of these problems aren't yet clear.
Problems for the heart
One of the first indications of a potential problem came all the way back in March, courtesy of researchers in Wuhan who had tracked some of the first COVID-19 patients. In their study, roughly 20 percent of a group of 416 hospitalized patients had some indications of cardiac problems. The researchers used a variety of blood tests to look for proteins that normally reside inside cardiac muscle cells but can be released into the blood when those cells get damaged. (For an example of one of the assays the Wuhan researchers used, see this description of the troponin test that's commonly used to check for heart problems.)
https://arstechnica.com/science/2020/09/evidence-slowly-building-for-long-term-heart-problems-post-covid-19/