What is commotio cordis? Traumatic injury that may have led to Damar Hamlin’s cardiac arrest

Emergency room specialist says trauma likely happened just as heart was about to beat again

Damar Hamlin was taken to hospital in critical condition after the Buffalo Bills safety collapsed on the field after a tackle during a game against the Cincinnati Bengals.

The team said in a statement that the 24-year-old had suffered cardiac arrest on Monday night. Mr Hamlin received CPR on the field before he was taken to a hospital.

“It’s very reassuring to find out that they actually were able to restore cardiac activity on the field,” Dr Anthony Cardillo told CNN. “This is critical, and it’s really going to be critical in his further developments.”

“A lot of us have been looking at these videos and surmising that what most likely happened is a traumatic cardiac arrest,” the emergency room specialist added.

“When he was hit in that chest anteriorly, as hard as he was, it’s a phenomenon known as commotio cordis. This is when you get traumatic injury to the anterior chest, just as the heart is getting prepared to have another beat,” he said.

“It’s during that repolarization phase and the electromechanical activity of the heart ... the heart is fueled by electrical impulse,” Dr Cardillo noted. “If you have trauma at an exact moment, when that heart is getting ready to repolarize and beat again, you will go into cardiac arrest.”

The doctor said Mr Hamlin’s survival was a “testimonial to the quick action of the medical professionals on that field that saved his life”.

The University of Connecticut states that commotio cordis can be prompted by a chest wall impact and tends to occur in athletes between the ages of eight and 18 playing baseball, hockey, lacrosse, or any other sport in which an athlete may be struck in the chest by some kind of item.

Athletes active in martial arts may also be affected if they’re struck in the chest. The university adds that if CPR and defibrillation are not quickly administered, it’s unlikely that an individual will survive.

“When you go down like that, you’re having what’s called brain anoxia, or no oxygen to the brain. Similar to when a child falls in the pool, for example. And that scenario, it is really seconds that matter,” Dr Cardillo said.

“How long was the brain deprived of oxygen?” Dr Cardillo said. “It sounds like he was on the field for 10 or 15 minutes before they took them in the ambulance. And we didn’t really get a good visual [of] what was happening, but you have to imagine that CPR was started, they defibrillator him, and they were giving him oxygen. Those are all very important things.”

The physician added that Mr Hamlin “has to be sedated at this point, just to protect his body. He’s been through a lot right now. Whenever the body suffers a cardiac arrest and CPR is instituted, you want to really get that body to relax”.

He added that “they will slowly start weaning off that sedation to see how his body responds, to see if he’s breathing”.

“We are presuming that he had a cardiac event secondary to the anterior chest trauma, but we wouldn’t rule out the possibility of a cervical spinal injury,” he said.