Athletes and COVID-19: How concerned do we need to be in mild COVID-19 cases?
As I write this article, its been six months since the COVID-19 pandemic resulted in countries closing down and limiting travel, entertainment, dining and sports in an attempt to slow the spread of the virus. As some countries have stabilized since the first wave of COVID-19 infections, some sporting events have slowly started to return.
France is entering the third week of its iconic Tour de France professional cycling race, moved from its traditional three weeks in July to a late August start, but with the entire route intact. Cyclists and teams are quarantined in a strict isolation bubble with essentially no contact with fans.
The National Hockey League (NHL) and National Basketball Association (NBA) have resumed their 2019-20 seasons with playoffs while playing in front of empty arenas and playing games in a centralized location instead of the teams’ home towns.
The National Football League (NFL) has kicked off its 2020 season with shortened training camps and no preseason games. While not maintaining a strict isolation bubble like other leagues, the NFL has developed strict COVID-19 prevention protocols for all 32 teams, as well as COVID-19 testing guidelines for players and team personnel.
The question I hear is why do we have these COVID-19 prevention and testing plans in place for otherwise young and healthy professional athletes?
The reason is that COVID-19 infections are not limited to a respiratory infection like influenza or the common cold. Instead, the SARS-CoV2 virus that causes COVID-19 also causes cardiac, kidney and neurologic issues as well, even in otherwise young and healthy people.
There have already been a handful of professional and college athletes that have tested positive for COVID-19 and then developed cardiac issues including myocarditis, which is usually due to a viral infection of the heart and can lead to scarring of the heart and potentially long-term cardiac issues. Most notable was starting Boston Red Sox pitcher Eduardo Rodriguez who was diagnosed with COVID-19 prior to returning to the MLB team after COVID-19 shut down the league in March. Rodriguez was initially cleared to play in mid-July, but was then diagnosed with myocarditis a week later. Since myocarditis can take three to six months to fully recover, Rodriquez will miss the rest of the 2020 baseball season.
Denver Broncos football linebacker Von Miller is another professional athlete that was diagnosed with COVID-19 and found returning to workouts challenging. ((https://www.nytimes.com/2020/05/29/sports/coronavirus-survivors-athletes.html))
We already know that underlying medical problems like high blood pressure, diabetes and obesity may lead to worse outcomes with COVID-19. But until now, we thought that healthier people like athletes would have a much milder course of the disease.
COVID-19 infections and the heart – The Germany Experience
In July 2020, JAMA Cardiology published a study by German researchers that evaluated 100 patients recovering from COVID-19 infections. These patients all had a significant workup, with blood tests and cardiac imaging which including cardiac magnetic resonance imaging (cardiac MRI). (1)https://jamanetwork.com/journals/jamacardiology/fullarticle/2768916 The researchers were curious on the potential long-term cardiac impact after COVID-19 infection.
These patients in the study group, with an average age of 49 years old, were significantly older that typical professional athletes (expect for Tom Brady). However, the concerning finding which could also affect younger athletes was that 78 of the 100 patients had abnormal cardiac MRIs, with 60% (60 of 100) of the patients having cardiac inflammation. More concerning is that the cardiac MRIs were done, on average, about 71 days after the patient was first diagnosed with COVID-19. So these cardiac MRI findings of cardiac inflammation were not an acute phase, still infected with COVID-19 findings. This was documented continued cardiac inflammation over 2 months after their COVID-19 infection and in some cases, cardiac inflammation was still present three months after they were originally diagnosed with COVID-19 (The actual timing of the cardiac MRIs ranged between sixty-four (64) and ninety-two (92) days after diagnosis with COVID-19.)
Athletes and COVID-19
One argument thrown around is that COVID-19 is an “old person’s” disease or that approximately 50% of patients that test positive for COVID-19 have no symptoms at the time of their positive test.
More importantly, do athletes with prior COVID-19 infection need any special clearance before being allowed to return to play and their sporting activity?
A group at The Ohio State University looked at this specific issue in September 2020, and published their initial data as a research letter in JAMA Cardiology (2)https://jamanetwork.com/journals/jamacardiology/fullarticle/2770645.
The study detailed their findings on Ohio State college athletes with prior COVID-19 infection that had cardiac MRI done as part of the college’s return to play medical evaluation.
The researchers were able to enroll 26 college athletes that had previously tested positive for COVID-19 during the summer. None of the athletes had COVID-19 symptoms requiring hospitalization
Out of 26 college athletes studied, a total of 4 (15%) of those Division 1 college athletes had an abnormal cardiac MRI. Only two of the four athletes were symptomatic with complaints of mild shortness of breath while the other two athletes had no symptoms whatsoever.
The Ohio State researchers did not think that the cardiac MRI findings were due to an exercise response since the T2 phase of the cardiac MRI demonstrated an increase of from 52 to 59 milliseconds. This increase in the T2 phase on cardiac MRI would indicate the possibly of inflammation of the heart consistent with myocarditis. (3)https://www.karger.com/Article/Fulltext/478901
There are some details in this study that could impact their findings. The one issue with the Ohio State study could be the short time frame between when the athletes were diagnosed with COVID-19 and when they had their cardiac MRI.
In most cases, the cardiac MRI was done around 2 to 3 weeks after diagnosis, but in some cases, as soon as 11 days after diagnosis. (4)Table 2 from the research letter
We don’t yet know if this cardiac inflammation seen on the cardiac MRI is an acute phase reaction due to viral load and ACE-2 receptors on the heart or if this is an indication of possible longer term issues in these athletes. The four athletes that had cardiac MRIs consistent with myocarditis were tested at days 11,12, 17 and 23 from diagnosis of COVID-19. But with the German study showing continued cardiac inflammation past 2 months, this is an area of concern that needs further followup.
Follow up cardiac MRIs would be helpful to determine the need for long-term follow up of these athletes.
Late Gadolinium Enhancement (LGE) in Athletes after COVID-19
The Ohio State also demonstrated that 12 of the 26 athletes had some evidence of late gadolinium enhancement on cardiac MRI. Gadolinium is a dye injected into the vein during cardiac imaging tests. Damaged heart cells take up the gadolinium, but healthy heart cells don’t. (5)https://www.ahajournals.org/doi/10.1161/CIRCIMAGING.113.001144 The positive LGE group included the 4 athletes with myocarditis changes on cardiac MRI as well as 8 additional athletes.
Late gadolinium enhancement on cardiac MRI is considered to be an indication of heart (myocardial) damage.
Return to play testing of athletes after COVID-19
The Ohio State study of myocarditis and cardiac inflammation and damage in otherwise young and healthy college athletes is concerning on several levels. The first is that it means potentially COVID-19 causes much more damage in otherwise “milder” infections that we previously thought.
Initially, it was believed that if the initial COVID-19 infection didn’t cause symptoms serious enough to require hospitalization, then patients should have a full recovery. However, more research is coming out that shows there are some patients that have “mild” COVID-19 infections that may require much longer recovery time and need closer followup that previously believed based on the Ohio State and German studies.
There have been previously published guidelines on return to play for athletes after COVID-19 in both the U.S.
(6)https://jamanetwork.com/journals/jamacardiology/fullarticle/2766124 and Europe (7)https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357275/#CR15 as well as expert opinion pieces published. (8)https://blogs.bmj.com/bjsm/2020/04/24/the-resurgence-of-sport-in-the-wake-of-covid-19-cardiac-considerations-in-competitive-athletes/(9)https://www.acc.org/latest-in-cardiology/articles/2020/05/13/12/53/exercise-and-athletics-in-the-covid-19-pandemic-era (10)https://www.acc.org/latest-in-cardiology/articles/2020/07/13/13/37/returning-to-play-after-coronavirus-infection However, these findings of cardiac myocarditis in otherwise healthy young athletes may lead to rethinking those return-to-play guidelines.