Growing evidence suggests the coronavirus can damage the hearts of even the young and physically fit.
Research published Friday in the journal JAMA Cardiology found that 4 out of 26 college athletes had signs of a heart condition called myocarditis after recovering from COVID-19.
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The findings were hinted at in late August, when Dr. Wayne Sebastianelli, director of athletic medicine at Penn State, said in a discussion with school board members that 30 percent of Big Ten athletes who had COVID-1
Scott Gilbert, a spokesperson for Penn State Health, told NBC News that Sebastianelli had misstated the results at the time and apologized for any confusion. Gilbert added that Penn State was not involved in the research and that there were no cases of myocarditis in the school’s COVID-19 positive student-athletes.
In fact, the new study was led by doctors at Ohio State University Wexner Medical Center, who were evaluating the safest ways to put off athletes in the fall. Ultimately, the Big Ten Conference, which includes both Ohio State and Penn State, decided not to play this fall.
“We’ve been asked this question about what would be the safest way to send them back to competitive play,” said study co-author Dr. Saurabh Rajpal, Ohio State cardiologist. “We decided in our group that in addition to the usual recommendations, which were a clinical exam and symptom research, we would also do a cardiac MRI to get more information and to see what the virus does to athletes’ hearts.”
The research included both male and female athletes in basketball, lacrosse, track and field, soccer and football. It was confirmed that all have recovered from COVID-19 and none required hospital or specific treatment. Twelve of the athletes reported mild symptoms of COVID-19, including sore throats and shortness of breath or fever, while the remaining 14 were asymptomatic.
To study the effects of the virus on the heart, the athletes performed several tests and a cardiac MRI to visualize the heart.
MRIs revealed that four athletes – all men with no pre-existing conditions – had signs of myocarditis. Two reported having mild symptoms of COVID-19; the other two were asymptomatic.
It was surprising that not all athletes with myocarditis exhibited symptoms of COVID-19, said Dr. Brett Toresdahl, a sports medicine physician at the New York City Special Surgery Hospital. This is because myocarditis was initially recognized in hospitalized patients with COVID-19.
“What this study shows is that myocarditis can occur even after less severe and even asymptomatic cases” of COVID-19, said Torsedahl, who was not involved in the research. “Therefore, an athlete’s risk of myocarditis may not be related to the severity of their symptoms.”
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Eight other athletes also had signs of heart scarring, but it’s unclear whether this was related to COVID-19 or a normal adaptation of the heart.
Although the condition often goes away on its own, in rare cases it can cause sudden death from cardiac arrest.
Rajpal warned that the study was small and more research is needed to confirm whether COVID-19 contributed to athletes’ myocarditis.
In fact, athletes’ hearts typically undergo changes as they adapt to high intensity training, which allows their heart to function more efficiently. But Dr Ali Nsair, director of sports cardiology at UCLA, said the results were abnormal even for an athlete.
Based on what is known about the virus, Rajpal said, it is likely that the heart condition was linked to COVID-19. In fact, previous research has found evidence of heart inflammation in cured COVID-19 patients.
However, the athlete’s MRIs were the only evidence of heart damage. None of the athletes had any abnormalities on the other tests, including an ECG, which measures heart rhythm, or a blood test for levels of troponin, a protein that indicates heart damage.
Nsair, who was not involved in the research, said it was because the abnormalities were detected only with MRI and not blood tests or ECGs. It raises the question of whether any athlete who tested positive for the coronavirus should have an MRI of the heart before they are cleared for competitive play, he said.
In the state of Ohio, Rajpal said, this is the current protocol for recovered COVID-19 athletes before returning to strenuous activity.
Rajpal added that athletes with myocarditis are advised to rest for three months before returning to play, in accordance with American Heart Association guidelines. And when they come back, they should be wary of symptoms, especially if they experience unusual shortness of breath or chest pain.
Others agreed that rest is essential.
“If we see a patient, professional athlete or otherwise, with this amount of inflammation, we recommend that they avoid any exercise until it is proven to be clear,” Nsair said.
Toresdahl said his advice to an athlete with signs of myocarditis “right now would be to rest simply because we don’t know their risk of sudden cardiac arrest resulting from COVID-19 myocarditis.”
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