No evidence that COVID-19 vaccines cause sudden cardiac arrest or myocarditis in athletes

It’s now almost a rule of thumb: As soon as an athlete falls to the bottom with a sudden cardiac arrest, social media is awash with claims that COVID-19 vaccinations are responsible. This was the case with English footballer Charlie Wyke, cyclist Sonny Colbrelli and, most recently, with college basketballer, and son of LeBron, Bronny James. Within the view of Harald Jorstad, Sports Cardiologist at Amsterdam UMC, there isn’t any evidence to support these claims, but timing of the vaccination might be structured to not negatively influence performance. This text is, today, published within the British Journal of Sports Medicine.

Jorstad, along with Joelle Daems, a PhD candidate in Sports Cardiology at Amsterdam UMC, analyzed all of the prevailing literature on the subject and located no available evidence for a rise in sudden cardiac arrest or a rise in myocarditis in athletes after COVID-19 vaccination.

“We analyzed all the studies we could find. Including one from Australia that included greater than 4 million people. There researchers found that neither the rates of sudden cardiac arrest nor the rates of myocarditis as cause for cardiac arrest increased after vaccination. Myocarditis occurs most frequently in young people, especially in men.”

In rare cases, covid infection may cause myocarditis. And in even fewer cases, it will possibly be a side effect of vaccination, after which the myocarditis is frequently milder than after an infection. “Although athletes – as a result of their relatively young age – are at increased risk of developing myocarditis, we found no evidence within the studies that COVID-19 vaccination combined with intense exercise increased this risk even further,”‘ says Daems.

While athletes could be hesitant to receive the COVID-19 vaccination as a result of performance considerations, this Amsterdam UMC article highlights that the vaccine is mostly well tolerated. Most athletes only experience mild short-term unintended effects. A study of 127 Olympic and Paralympic athletes demonstrated that only eight athletes were unable to coach on the day of the vaccination, with seven of the eight resuming training the following day.

Small decrease in V02 max

“Surprisingly, we did nevertheless see a small decrease in VO2 Max in a single study,” says Daems. A study from the Netherlands and Belgium demonstrated a small but statistically significant decrease in VO2 max seven days after vaccination. VO2 Max indicates how much oxygen a person can devour during exercise and is usually seen as a measurement of endurance fitness.

“The dimensions of this decrease was very small, and it seems unlikely that this decrease has any clinical relevance. Furthermore, this effect could well be temporary,” adds Daems

“This, combined with the previous findings, shows us that athletes haven’t any reason to be concerned. Although those athletes who’re considering a vaccine this winter should probably do it outside of major competition periods,” concludes Jorstad.