Coronavirus
A Change of Heart: Why Covid-19 Myocarditis Seems Less Threatening to Athletes Now Than Before
Just two months ago college athletic conferences were alarmed enough to cancel sports. What led them to reverse course?
The novel coronavirus has been known to affect organs from the brain to the GI tract and almost everywhere in-between. One of the most concerning features of SARS-CoV-2 is its ability to spread easily and silently as infected individuals may not show obvious signs of infection. Of further concern has been the revelation within the past two months that Covid-19 may silently damage the heart without producing overt cardiac symptoms.
One of the first investigations to sound the alarm revealed evidence of heart muscle inflammation in 78 of 100 patients in Germany who had recovered from Covid-19. This inflammation was discovered by way of cardiac magnetic resonance imaging (CMR) and led interpreters of the study to question if the imaging findings might represent a condition called viral myocarditis.
The idea that infected individuals with minimal or no symptoms of Covid-19 could unknowingly suffer from heart damage had enormous implications, particularly for college athletics. At the time, many key decision-makers believed canceling fall sports was the only way to adequately preserve the safety of student-athletes. Few were surprised, therefore, in mid-August when the Pac-12 and Big Ten conferences announced cancellations for the fall.
Seeing patients first-hand with myocarditis from Covid-19 and knowing how the condition is diagnosed, made me wonder how someone with mild or no symptoms could be considered to have myocarditis on the basis of CMR alone without a cardiac biopsy.
What is viral myocarditis?
Viral myocarditis is an inflammatory condition that can cause temporary or even permanent damage to the heart muscle. Viruses that can cause myocarditis include influenza, coxsackievirus, adenovirus, and Epstein-Barr virus, among others. As of this year, SARS-CoV-2 can be added to the list.
As the gold standard, a definitive diagnosis of myocarditis can only be made by a cardiac muscle biopsy. However, as one might suspect, performing a biopsy of the heart is not a simple or risk-free procedure. With this knowledge, the European Society of Cardiology developed criteria for a clinical diagnosis of myocarditis which requires 1 of 4 clinical and 1 of 3 diagnostic features:
- Clinical features: acute shortness of breath, chest pain, palpitations or passing-out, or cardiogenic shock.
- Diagnostic features: abnormalities on an electrocardiogram (EKG), elevated serum troponin (a cardiac enzyme) level, or functional or structural abnormalities on cardiac imaging (echocardiogram or CMR).
Personal experience
In the past two months, I’ve had over 120 patient encounters with those hospitalized with Covid-19. Most of the patients suffered primarily from respiratory symptoms of the virus. However, I have seen a few individuals with evidence of cardiac involvement and what I would consider myocarditis based on the clinical criteria above.
Seeing patients first-hand with myocarditis from Covid-19 and knowing how the condition is diagnosed, made me wonder how someone with mild or no symptoms could be considered to have myocarditis on the basis of CMR alone without a cardiac biopsy. As it turns out, I wasn’t the only one.
Coming together
In fact, others were also concerned that findings on CMR in isolation without other signs or symptoms might not be a very relevant piece of data. In response, a group of 51 clinicians including many cardiologists and radiologists signed an open letter to multiple medical organizations such as the American Heart Association and the American College of Physicians stating:
“We request that you offer clear guidance discouraging CMR screening for Covid-19 related heart abnormalities in asymptomatic [patients].”
Studies thus far using CMR to evaluate patients with Covid-19 have largely been retrospective rather than prospective and lacked key comparison groups such as those with myocarditis related to other viruses.
Know what’s in your toolbelt
One aspect of the art of medicine is to interpret test results in their proper context. That includes understanding the pre-test probability (i.e. the likelihood a patient has a disease prior to a test) as well as the post-test probability (i.e. how a test result changes the likelihood of a particular diagnosis).
Some imaging tests produce unintended findings. For example, a radiologist might discover a mass on the adrenal gland of a patient undergoing a CT scan to look for kidney stones. In some cases, these ‘incidentalomas’ may be important discoveries that lead to early diagnosis and treatment of cancer. But in other cases, incidental findings may lead to unwarranted worry and testing.
Experts weigh in
Context isn’t just important for imaging tests. It applies to other tests as well, like lab tests and EKGs. To evaluate athletes testing positive for SARS-CoV-2, Matthew Martinez, MD, chair of the American College of Cardiology’s Sports and Exercise section, offers the following recommendations:
“My approach is to evaluate anybody with a history of Covid infection and, first, determine whether it was an important infection with significant symptoms or not. And then, if they’re participating at a high level or are professional athletes, I would suggest an EKG, echocardiogram, and troponin.”
Notably missing from this guidance is the routine use of CMR. Why?
More recently, a study of 26 athletes at Ohio State University (OSU) found 15% to have CMR findings suggestive of myocarditis. But none of them had cardiac-specific symptoms, elevated troponin, or EKG changes. The study’s lead author, Saurabh Rajpal, MD, reported that the findings “could suggest prior myocardial injury or it could suggest athletic myocardial adaptation.”
Studies thus far using CMR to evaluate patients with Covid-19 have largely been retrospective rather than prospective and lacked key comparison groups such as those with myocarditis related to other viruses. Dr. Rajpal further explains, “I don’t think this is a Covid-specific issue. We have seen myocarditis after other viral infections; it’s just Covid-19 is the most studied thus far.”
…A better understanding of myocarditis undoubtedly played a crucial role in the decision [to allow athletes to play this fall].
Turning the tide
With consensus gathering among experts that CMR data should be interpreted cautiously and the fact that some other conferences have already allowed athletes to compete, it again came as a little surprise last week that the Big Ten (of which, incidentally, OSU is a founding member) reversed its decision and indeed will now allow athletes to play this fall. This, in turn, was followed by the Pac-12’s about-face just days later.
While conference leaders cited multiple reasons for the change, including the ability to perform rapid antigen screening tests on athletes daily, a better understanding of myocarditis undoubtedly played a crucial role in the decision. That is not to say that athletes are no longer at risk for myocarditis or other complications from Covid-19, however.
Somber news
Jamain Stephens, a college football player from California University, recently died from complications of Covid-19. While California University had canceled football and in-person classes for the fall, Stephens was on campus for training and workouts. His passing serves as a sober reminder of the risk for athletes during the pandemic whether or not they are actively involved in a competition.
A balancing act
Many, myself included, have doubted at times whether the benefits of organized sports are worth the risk of harm to athletes, coaches, officials, and fans during the pandemic. Cameron Wolfe, MD, an infectious disease specialist at Duke University and chair of the Atlantic Coast Conference medical advisory group, discussed the issue in an interview last month.
“Can we safely have two teams meet on the field? I would say yes. Will it be tough? Yes. Will it be expensive and hard and lots of work? For sure. But I do believe you can sufficiently mitigate the risk of bringing Covid onto the football field or into the training room at a level that’s no different than living as a student on campus.”
Despite the ever-changing landscape of the pandemic, Dr. Wolfe’s words are as true today as they were then. While myocarditis remains a potential concern for anyone suffering from Covid-19, seeing those in the medical community come together to compile the latest data and present it clearly to policy-makers and the public is a decisive victory for everyone involved in sports.
