On Monday, NBA star LeBron James’s son, Bronny James, was hospitalized after experiencing cardiac arrest during basketball practice at the University of Southern California. While the incoming USC freshman has since been released from the intensive care unit and is now listed in stable condition, according to a family spokesperson, the incident has renewed public speculation surrounding cardiac arrest and myocarditis related to the COVID-19 vaccine.
Earlier this year, Buffalo Bills safety Damar Hamlin collapsed on the field following a hit during a Monday Night Football game against the Cincinnati Bengals. Shortly thereafter, some people on social media began pointing blame at the COVID-19 vaccine in an latest attempt to undermine the vaccine’s efficacy.
At the time, Dr. Michael Emery, cardiologist and co-director of the sports cardiology center at Cleveland Clinic, told Fortune, “The [suggested] link between the COVID-19 vaccine [and cardiac arrest] is wildly and irresponsibly speculative from a very vocal minority.”
According to the Sports Institute, roughly one or two in every 100,000 young athletes experience a sudden cardiac arrest each year, with African American males being at greater risk (nearly six in 100,000).
Sudden cardiac arrest in young athletes is typically caused by a “structural or electrical abnormality of the heart.” In some cases, excessive stress can trigger a rare underlying heart issue that has not been previously detected, or has not been picked up by scans, and can “put the heart into a rhythm that is not sustainable for long periods of time, and hence, the patient usually collapses,” Dr. Doris Chan, an interventional cardiologist at NYU Langone Hospital–Brooklyn, previously told Fortune.
What is myocarditis?
Myocarditis is inflammation of the heart. Although vaccines and viruses, not just those related to COVID-19, can cause myocarditis, instances are rare. Myocarditis can cause a person to become very sick and require hospitalization. It can also lead to , which is an electrical malfunction of the heart.
“Myocarditis is often caused by viruses—any viral infection can cause it,” explained Emery. “It probably has to be a genetically susceptible person, but we don’t understand why some people get a virus and do fine and why some people get myocarditis.”
A study published in the American Heart Association journal found that the risk of developing myocarditis following a COVID-19 vaccine booster is low, and when it does occur, cases are typically mild. Teen boys and young men have the highest risk for myocarditis.
“We’ve always known that viruses can cause heart problems, and COVID is no different than other viruses that cause heart problems,” said Emery. “The problem is, so many people got COVID all at once that it looks like there’s a huge rash of [heart problems].”
If you have shortness of breath, excessive heart palpitations, or chest discomfort, then Emery recommends calling 911 and getting evaluated in a more comprehensive setting.
“You’re more likely to develop a serious illness from the COVID virus itself than you are a COVID vaccine,” Emery continued, as people who’ve contracted the virus can sometimes develop lingering effects, such as long COVID; require hospitalization; or may die from complications related to COVID-19.
“This is a case where correlation does not equal causation,” Emery said.
