Return to competitive sports; Follow-up critical
Experts are much more confident, however, about when teens admitted with viral myocarditis can return to competitive sports. But Dr. Butts said he suspects the guidelines for these children aren’t followed as closely as they should be. The American Heart Association recommends waiting 6 months after discharge and ensuring the athlete has a normal echocardiogram, Holter monitoring, and stress test.
“It’s incredibly important to have them come back and see the cardiologist 6 months after admission,” Dr. Butts said. “The only patient I’ve ever had who died 6-7 months post myocarditis is somebody who, during their stress test, had increasing ventricular ectopy. I told him not to do sports. He didn’t listen to me and unfortunately passed away – I’m assuming from arrhythmia.”
COVID and vaccine-associated myocarditis
Vaccine-associated myocarditis is substantially milder than viral myocarditis, Dr. Butts said. A small study from a single center in Atlanta found that ejection fraction at admission was normal, around 56%, in those with vaccine-associated myocarditis, compared with 45% with non-COVID viral myocarditis and 50% with multisystem inflammatory syndrome in children or myocarditis from COVID-19. All patients with vaccine-associated myocarditis had normal function at discharge, compared with 73% of those with viral myocarditis and 93% with COVID-associated myocarditis.
While 22% of those with vaccine-associated myocarditis were admitted to the ICU, twice as many (40%) with viral myocarditis were, and three times as many (68%) with COVID-associated myocarditis ended up in intensive care.
Dr. Butts also noted a Morbidity and Mortality Weekly Report from the Centers of Disease Control and Prevention that found teen boys had two to six times greater risk of heart complications after COVID-19 infection than after COVID vaccination.
In terms of direct comparisons, vaccine-related myocarditis occurred about 12-18 times per 100,000 doses for boys ages 5-11 years, compared with cardiac involvement in 93-133 cases out of 100,000 COVID-19 infections. Boys aged 12-17 years experienced 12-21 cases of myocarditis per 100,000 doses of the vaccine, compared with cardiac involvement in 50-64 out of 100,000 infections.
The bottom line, Dr. Butts said, is that cardiac involvement in MIS-C is common, but typically improves by discharge. “Vaccine-associated myocarditis is a mild clinical syndrome that has a very short duration, and, in my opinion, should never lead us to ever advise anybody not to get the vaccine. I’ve had many patients, even patients in their first year post transplant, who have gotten the COVID-19 vaccine and were just fine.”
Dr. Butts acknowledged that talking with families about the risk of myocarditis with the vaccine is challenging. He often starts these conversations by sharing the statistics, but he said relatable stories are the key. He will also relate the statistics to something the parents and teen will understand, whether it’s sports or another comparison. He does recommend that teens who develop vaccine-associated myocarditis complete the series and get the booster. Their chances of developing myocarditis again are extremely low, whereas “the likelihood of them being really ill from COVID-19 is much, much higher.”
Dr. Butts and Dr. Han had no disclosures. The presentation involved no external funding.