A peer-reviewed study examining professional athletes who, after contracting COVID-19, received return-to-play cardiac screening has found very few cases of inflammatory heart disease among its participants, suggesting a return to pro sports following COVID-19 infection can be safely achieved using a systematic screening program.
Several professional North American sports leagues collaborated on the effort, including the NHL, MLB, NBA, NFL, WNBA and MLS.
A total of 789 athletes who had COVID-19 participated in the study, which took place between May and October 2020 and sought to gauge how often the leagues' return-to-play cardiac screening techniques found instances of inflammatory heart disease.
Imaging evidence showed that, among those participants, five athletes (0.6 per cent) had myocarditis or pericarditis, two forms of inflammation in the heart which can weaken the organ. No athletes who underwent cardiac screening and then continued their professional sport participation experienced an adverse cardiac event, such as a heart attack.
As with all research, the study had limitations. Some of these stemmed from having different researchers, at different clinics, in different states and countries conducting the screening, creating an undesirable potential for variance.
But perhaps the most notable was that nearly all -- 98.5 per cent -- of the athletes in the study were men.
Prior studies on the risk COVID-19 poses to the heart drew more uncertain conclusions, too.
One paper, published in July before several college conferences postponed their sports seasons, ran MRIs on 100 people who had COVID-19 and found at least some signs of myocarditis in 60 of them. Another, which looked at 26 Ohio State athletes who experienced COVID-19 with mild or no symptoms, found evidence of possible myocarditis in five of them and lesser abnormalities in nine others. The prevalence of myocarditis was especially concerning as, even before the pandemic, it was a leading cause of death in otherwise healthy, young athletes.
Long-term follow-up on this latest study's participants remains ongoing, and will be an essential part of judging how effective these cardiac screening measures are -- as will expanding research to include other levels of athletes.
Still, the limited number of inflammatory cases detected was a welcome finding that can help chart a path forward, both for future research and for improving return-to-play measures, by highlighting the importance of including cardiologists with imaging expertise in the process to properly identify disease and minimize delays in an athlete's return.
"While long-term follow-up is ongoing, few cases of inflammatory heart disease have been detected," the study's authors wrote in their conclusion. "Safe return to professional sports activity has thus far been achieved."