One factor behind the Big Ten and Pac-12 decisions to postpone college football this fall was a growing concern about the connection between COVID-19 and myocarditis, a rare inflammation of the heart muscle.

Dr. Brian Hainline, the NCAA?s chief medical officer, said Thursday morning the NCAA is aware of about 12 cases of myocarditis among athletes. Indiana freshman offensive lineman Brady Feeney went to the emergency room with breathing issues and is still struggling with heart complications, according to?a Facebook post from his mother.

The condition is one of the side effects of contracting the novel coronavirus that is only beginning to enter the public radar alongside other, more well-documented issues such as loss of smell or taste, fever and respiratory issues. And while rare, it?s a condition that seems to have?spooked some top officials?in Power Five conferences.

?I?m very concerned about myocarditis,? said Dr. Colleen Kraft, an infectious disease expert from Emory University. ?One of the things as a frontline physician is that I don?t see the statistics as numbers, I see them as individual patients. I?m currently this week taking care of people with very sad stories that could have been prevented.

?It?s not something they did or didn?t do right or wrong. I think we are playing with fire. One case of myocarditis in an athlete is too many.?

What is known about the link between myocarditis and COVID-19?

Myocarditis is usually caused by a viral infection ? including the common cold or H1N1 ? that if left unchecked can lead to heart damage or potential cardiac arrest.

At the start of the pandemic, doctors associated the condition only with patients with underlying conditions or those hospitalized from severe COVID-19 cases. A disturbing trend has started to emerge recently, however, of younger, healthier Americans developing this condition and at a higher rate compared with other viruses.

It has become enough of an issue to give those around college sports pause, and there is clear evidence to dispel the false notion that athletes and younger, healthier people who contract the virus will easily bounce back without issue. This is a condition that could come with long-term side effects.

Hainline and other members of the?NCAA advisory board had an hourslong call with?cardiology experts?this week to seek more guidance.

?I recall even 30 years ago when I was at a conference looking at tennis medicine and how we guide tennis players with flu-like symptoms or cold-like symptoms, we said you absolutely cannot train when you have a viral syndrome because there?s a risk of myocarditis,? he said. ?This has been around for a long time. It?s here with COVID-19 and we?re taking it seriously.?

How common has myocarditis been so far?

Not very common, although there have been a few high-profile cases.

Red Sox pitcher Eduardo Rodriguez will miss the 2020 season after developing myocarditis after contracting COVID-19. And college administrators certainly took note of Feeney?s story and his mother?s social media post.

?That?s one of the things that while isn?t a common thing, is a scary thing, from a ruin your life standpoint in addition to a career standpoint,? Dr. Michael Terry, an orthopedic surgeon who specializes in sports medicine at Northwestern Memorial Hospital, said during a phone interview Wednesday. ?I think that?s on people?s minds.?

Experts also aren?t certain on how common it is for COVID-19 patients to develop the condition, considering some cases have certainly gone undetected.

Dr. Brian Cole, a sports medicine surgeon at Midwest Orthopedics at Rush University Medical Center, called it a silent problem that could be devastating. ?We always err on the side of conservatism and appropriately so,? Cole said.

?This is potentially one of the more devastating consequences, if someone were to get myocarditis, and not know it and return to sport. ?It seems to be an infrequent problem, but not one we are not prepared to ignore at this juncture.?

What changes have sports leagues made?

Leagues are beginning to update and adjust their COVID-19 guidelines for athletes. Some are instituting cardiac screenings during the physical process before an athlete takes the field and requiring one for after an athlete tests positive ? even if they never displayed any symptoms ? to check for structural or biological changes to the heart before they are cleared to play.

Experts recommend giving athletes an EKG, echocardiogram or sometimes even an MRI for the heart to remain diligent in testing. The costs of the tests also must be considered, as not every college has the same access to such resources and that could lead to increased risk at some schools, even in the same conference.

?The guidance today is even more rigid in terms of the processes that must happen after an (athlete) ? even who has been asymptomatic ? tests positive,? Hainline said. ?This is based not on our recommendations solely, but the recommendations of probably the leading sports cardiologist In the country.?

How much more is there to be learned about myocarditis?

Cole is a managing partner at Midwest Orthopedics at Rush Hospital, and the organization has helped advise and implement a return to sports policy for several major leagues, including the NBA, MLS and MLB.

They are beginning to craft a high school response as well. And although he had yet to encounter myocarditis among high school athletes, he expressed trepidation about the risks and it will be one he is keeping his eyes on while leaning on advice from cardiac experts.

This pandemic ? which has upended and affected nearly every stretch of American life ? is still new and experts have studied the virus and its lingering consequences for only about six months. That leaves a fair amount of uncertainty surrounding the link between myocarditis and coronavirus.

?We don?t know who is at higher risk for that sort of thing with regard to those people infected with COVID,? Terry said. ?So what else is causing myocarditis to occur in the few people that it has? Like everything with this, it seems like we?re learning a lot as we progress through.?

Jamal Collier ?Jamal Collier covers the Bulls and the NBA for the Chicago Tribune. A University of Illinois alum, he joined the Tribune after five years at, where he spent four seasons covering the Washington Nationals.

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