What to know about cardiac arrest in young athletes: Symptoms and causes

News broke on Tuesday that Bronny James, the eldest son of LA Lakers superstar LeBron James, had suffered a cardiac arrest during a training session with the University of Southern California the previous day. Thankfully, a statement put out by the James family has revealed that the 2024 NBA draft hopeful is in a stable condition and out of ICU.

As well as hoping for a positive outcome, perhaps one of the first questions that comes to mind when we hear of such incidents is just how a young athlete (James Jr. is just 18 years old) can be at risk of their heart stopping. Of course, we have seen other high-profile figures suffer a similar fate, including the Buffalo Bills’ Damar Hamlin and Danish soccer player Christian Eriksen.

Genetics, rather than injuries, most to blame

According to John P. Higgins, professor of cardiovascular medicine with McGovern Medical School at UTHealth Houston and sports cardiologist with the Houston Rockets, 25-year-old Hamlin collapsed as a result of commotio cordis, a disruption of heart rhythm caused by a blow to the chest, which then leads to sudden cardiac arrest (SCA).

That, however, is the not most typical instigator of SCA in young athletes, with most suffering as a result of undetected heart diseases or defects. Genetics are most often to blame, rather than injuries.

What are the leading causes of sudden cardiac arrest in young athletes?

Higgins explains that hypertrophic cardiomyopathy and congenital coronary artery anomaly are the two leading causes.

“Hypertrophic cardiomyopathy is a disease of the heart muscle. It starts to become too thick and stiff for blood to fill the heart and be pumped out effectively, Some hypertrophic cardiomyopathy patients are predisposed to ventricular arrhythmia (an irregular heartbeat) and SCA.”

“A congenital coronary artery anomaly is a heart defect,” Higgins continues. “An artery is in the wrong place, or coming from the wrong place, and not allowing proper blood flow to supply necessary oxygen and nutrients to the heart.”

Of course, intense physical exercise demands more blood flow from the heart, which vastly increases the chances of the diseases or defects being exposed.

How many athletes die from SCA per year?

Studies carried out suggest that about 1 to 50,000 or 1 to 80,000 young athletes die from sudden cardiac arrest per year, with a number of other heart conditions, including myocarditis (the inflammation of the heart muscle), heavily linked to SCA.

Three-point plan to combatting SCA

So, what can be done to prevent it or, in the worst case scenario, deal with it? Screening, staying hydrated and ensuring sports coaches and event organisers know CPR (cardiopulmonary resuscitation) make up Higgins’ three-point plan to combat sudden cardiac arrest.