Doctors explain what triggered Damar Hamlin's cardiac arrest
PHILADELPHIA (CBS) -- Buffalo Bills safety Damar Hamlin suffered cardiac arrest and received life-saving CPR right on the field during Monday Night Football.
It was a sight most of us will likely never forget.
There is very limited official information, but doctors have a pretty good idea of what caused this cardiac arrest based on what happened on the field.
"This is more than a one-in-a-million possibility," Dr. William Gray, of Main Line Health, said. "It's that rare."
Gray said it appears to be a freak accident that caused Hamlin to suffer a cardiac arrest after being hit in the chest.
"It appears to be a form of commotio cordis," Gray said. "A strike or a collision at just the right, timing at just the right spot on their chest, they can disrupt the electrical system of the heart in such a way the regular heart rhythm collapses."
On an electrocardiogram, the blue line shows where in between heartbeats, the disruption happens.
"Once the strike occurs here, you don't get the next beat, you just get a rhythm that doesn't have any beats," Gray said.
That leaves a person without a pulse and unconscious, which is why the quick CPR on the field was so critical – where Hamlin's heartbeat was restored.
"That buys them time. That gets circulation at least minimally going to preserve circulation most importantly to the brain," Gray said.
There are reports Hamlin is on a ventilator in critical condition. Doctors will be working to figure out if he had a pre-existing condition, and if there's residual damage from the cardiac arrest.
Gray said in today's age a sudden collapse due to commotio cordis is recoverable in most cases.
One doctor said this injury is more common in other sports.
"There are about 30 of these cases a year that happen in the United States," Dr. David Aguys, a CBS News Medical contributor, said. "They predominantly happen in kids, little league baseball. A ball is thrown by a pitcher and hits the person in the chest. It happens in soccer, when something causes that blunt force trauma, so remarkably rare."
Like with any cardiac event, quick response with CPR is critical
"CPR, we know, saves lives," Dr. Lawrence Philips, a cardiologist, said. "And by rapidly responding in a medical emergency, you tremendously increase the likelihood that someone will survive from cardiac arrest."
There were also reports an AED was used on the field, which can also be life-saving, restoring the heartbeat with a shock.
Doctors say it could take a couple of days to know what will happen with Hamlin. The fact that he received quick CPR is critically important.
Doctors also say there's a good possibility Hamlin could recover and resume his football career.