Sudden cardiac arrest: What is it and are athletes at risk?

Jan. 4—Buffalo Bills safety Damar Hamlin remained in critical condition Tuesday afternoon at University of Cincinnati Medical Center after suffering a cardiac arrest on the football field after a tackle during Monday night's Cincinnati Bengals-Buffalo Bills game.

Hamlin made the tackle, got up, then quickly fell back to the ground. A statement from the Bills said Hamlin's heartbeat was restored on the field via a defibrillator and chest compressions, and he was later sedated at the hospital. There were few other updates on his condition Tuesday.

Kettering Health is "the official health care provider for the Cincinnati Bengals," but a spokesperson on Monday explained they were not the emergency medical staff on the field assisting Hamlin. The spokesperson said the role of Kettering Health EMS staff at Paycor Stadium is to provide medical care to those in attendance, including Bengals friends and family, fans, employees, and vendors at the event.

What is cardiac arrest?

Sudden cardiac arrest is when there is an abrupt loss of heart function, leading an individual to lose consciousness and stop breathing. According to the Mayo Clinic, the condition usually results from a problem with the heart's electrical system that disrupts the heart's pumping action and stops blood flow to the body.

This is not a heart attack, which occurs when blood flow to a part of the heart is blocked. A heart attack can sometimes lead to sudden cardiac arrest if it triggers an electrical malfunction in the heart, according to the Mayo Clinic.

While Kettering Health officials did not want to speculate about what happened to Hamlin, Dr. Brian Schwartz, a cardiologist with Kettering Health, explained the risk of sudden cardiac death is rare, especially with athletes, as professional athletics organizations screen athletes for the most common issues that can lead to cardiac arrest.

"There can be other genetic or underlying heart conditions, but most athletes are screened for that," Schwartz said.

Heart problems are the biggest risk factors for cardiac arrest, according to the National Heart, Lung, and Blood Institute. Those can include coronary heart disease, arrhythmias, damage to the heart like heart inflammation, heart failure, or problems with the heart structure, like a congenital heart defect, cardiomyopathy, or heart valve disease.

Schwartz said the risk of cardiac arrest is higher in older patients, and Kettering Health saw three of those patients come in the on same day over the holidays. For a young, healthy individual, "it would be incredibly rare," Schwartz said.

Physical blow to the chest

In the case of cardiac arrest following an injury, Schwartz said the individual would have to get struck directly in the chest at the exact microsecond that the heart is vulnerable. The agitation of the heart causes an electrical malfunction in the heart that leads to ventricular fibrillation. Ventricular fibrillation is where the ventricles, which are the two lower chambers of the heart, quiver. Schwartz said that prevents the heart from pumping blood.

"There's no blood getting to the brain," Schwartz said.

The majority of people who suffer sudden cardiac death do not survive, he said. Approximately 350,000 cases occur each year outside of a hospital in the U.S., according to the American Heart Association, and the survival rate is less than 12%. CPR can double or triple the chances of survival.

Schwartz said the sooner a defibrillator, or an AED, can be applied the subject, the better off that individual is.

"If the CPR went on a long time and the brain is stunned or damaged, that could lead to either death or permanent impairment," Schwartz said.

For those who survive sudden cardiac arrest, doctors may place them in a medically induced coma for the next 24 hours and will very likely reduce their body temperature, Schwartz said. This is to help reduce potential brain damage. After that, over the next 24-48 hours, doctors slowly warm patients back up and start evaluating whether there was damage caused by the cardiac arrest.

Schwartz said about half of patients recover and the other have may have some permanent impairment from the cardiac arrest.

Cardiac incidents with athletes

In the cases that do impact athletes, Schwartz said sudden cardiac death is more common in baseball and hockey players. Over 90% of those cases are among men, with over 75% occurring in athletes less than 25 years old, he said.

Sudden cardiac death is the most frequent medical cause of sudden death in athletes, according to a 2016 study by a group of Massachusetts General Hospital physicians. The study cited an estimate that sudden cardiac death incidence ranged from 1 in 40,000 to 1 in 80,000 athletes per year.

A variety of young athletes have died from cardiac incidents of multiple types in recent decades. They include cases like figure skater Sergei Grinkov in 1995 (genetic anomaly), baseball player Darryl Kile in 2002 (blocked arteries), and basketball player Fab Melo in 2017 (heart attack).

A 2020 study of sudden death in soccer players worldwide found 617 players from 67 countries had suffered cardiac incidents from 2014 to 2018, with only 142 of them surviving, according to the study's examination of the FIFA Sudden Death Registry.

The Dayton area is not immune to cardiac tragedies with athletes, having lost former Springfield Catholic and NBA basketball player Jason Collier in 2005 to an enlarged heart, and University of Dayton basketball players Chris Daniels (1996) and Steve McElvene (2016) to cardiac deaths.

Those players collapsed and died away from the field of play. Some other athletes have suffered cardiac incidents during competition, sometimes on live TV, as happened to the Bills' Damar Hamlin on Monday night.

In 1971, NFL player Chuck Hughes collapsed during a Lions-Bears game and died of a cardiac condition. In 1990, college basketball player Hank Gathers fell during a Loyola Marymount game and died hours later. In 2007, during the U.S. Olympic Trials marathon, Ryan Shay collapsed and died that day of a cardiac incident.

However, there have been many players who have suffered cardiac incidents and survived.

Christian Eriksen, one of the world's best soccer players, collapsed on the field while playing for Denmark in the 2021 European Championships. He was revived on the field and is back competing today. The same happened in 2020 to then-University of Florida basketball player Keyontae Johnson, who is now back on the court. And multiple NHL hockey players who collapsed during games — Jiri Fischer, Rich Peverley, Chris Pronger and others — survived their cardiac incidents.