Growing evidence suggests that 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.
The findings were hinted at at the end of August, when Dr. Wayne Sebastianelli, the director of athletic medicine at Penn State, said during a discussion with school board members that 30 percent of Big Ten athletes who had COVID-19 showed signs of the condition, an inflammation in the heart muscle.
Scott Gilbert, a spokesman for Penn State Health, told NBC News that Sebastianelli had misstated the findings at the time and apologized for any confusion. Gilbert added that Penn State was not involved with the research, and that there have been no cases of myocarditis in COVID-19 positive student-athletes at the school.
In fact, the new study was conducted by doctors at the Ohio State University Wexner Medical Center, who were considering the safest ways to send athletes back in the fall. Ultimately, the Big Ten Conference, which includes both Ohio State and Penn State, decided against playing this fall.
“We were asked this question as to what would be the safest way to send them back to competitive play,” study co-author Dr. Saurabh Rajpal, a cardiologist at Ohio State, said. “We decided in our own group that in addition to the usual recommendations, which was a clinical exam and looking for symptoms, 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, soccer and football. All were confirmed to have recovered from COVID-19, and none required hospitalized or specific treatments. Twelve of the athletes reported mild COVID-19 symptoms, including a sore throat and shortness of breath or fever, while the remaining 14 were asymptomatic.
To study the virus’s effects on the heart, the athletes had several tests as well as a cardiac MRI to image the heart.
Let our news meet your inbox. The news and stories that matters, delivered weekday mornings.
The MRIs revealed that four athletes — all men with no pre-existing conditions — had signs of myocarditis. Two reported having mild COVID-19 symptoms; the other two were asymptomatic.
It was surprising that not all of the athletes with myocarditis had symptoms of COVID-19, Dr. Brett Toresdahl, a sports medicine physician at the Hospital for Special Surgery in New York City, said. This was because myocarditis was initially recognized in patients hospitalized with COVID-19.
“What this study shows is that myocarditis can also occur after less severe and even asymptomatic cases” of COVID-19, said Torsedahl, who was not involved with the research. “Therefore, an athlete’s risk of myocarditis may not be related to the severity of their symptoms.”
Download the NBC News app for full coverage of the coronavirus outbreak
Another eight athletes also had evidence of cardiac scarring, but it’s unclear if this was related to COVID-19 or a normal adaption of the heart.
While the condition often goes away on its own, in rare cases, it can cause sudden death from cardiac arrest.
Rajpal cautioned that the study was small, and more research is needed to confirm whether COVID-19 contributed to the athletes’ myocarditis.
In fact, athletes’ hearts typically undergo changes as they adapt to high intensity training, which allows their heart to perform more efficiently. But Dr. Ali Nsair, director of sports cardiology at UCLA, said that the findings were abnormal even for an athlete.
Based on what’s known about the virus, Rajpal said, it’s probable that the heart condition was linked to COVID-19. Indeed, earlier research found evidence of cardiac inflammation in recovered COVID-19 patients.
However, the athlete’s MRIs were the only evidence of heart damage. None of the athletes had any abnormalities in the other tests, including an EKG, which measures heart rhythm, or a blood test for levels of troponin, a protein that indicates damage to the heart.
Nsair, who also wasn’t involved with the research, said that it was concerning that abnormalities were picked up only on MRIs, and not bloodwork or EKGs. It raises the question of whether any athlete who’s tested positive for the coronavirus should have an MRI of their heart before getting cleared for competitive play, he said.
At Ohio State, Rajpal said, that’s 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 do return, they should be cautious about symptoms, especially if they experience unusual shortness of breath or chest pain.
Others agreed that rest is essential.
“If we see any patient, professional athlete or otherwise, with this amount of inflammation, we would definitely counsel them against any exercise until that’s been shown 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.”