A possible cause of Buffalo Bills safety Damar Hamlin’s collapse and cardiac arrest, witnessed in real time by millions of «Monday Night Football» viewers, was immediately recognized by heart experts who were also watching the game.

«I knew exactly what was going on,» said Dr. Nahush Mokadam, director of the division of cardiac surgery at The Ohio State University Wexner Medical Center. «The way he first got to his feet and then collapsed…it’s not what a concussion would look like.»

In a statement released Tuesday, Hamlin’s family thanked first responders and health professionals at the University of Cincinnati Medical Center, where he is being treated.

«On behalf of our family, we want to express our sincere gratitude for the love and support shown to Damar during this difficult time,» the family wrote.

As of Tuesday afternoon, no briefing at the hospital had been scheduled, NBC News confirmed.

Neither Mokadam nor any other physician interviewed for this article is involved in Hamlin’s treatment. In a statement, the Invoices He only said that Hamlin suffered a cardiac arrest, when the heart stops beating properly, and is in critical condition.

It was during the first quarter of Monday night’s game between the Invoices and the Cincinnati Bengals when the 24-year-old Hamlin tackled a Bengals receiver, who ran into his chest. Hamlin got to his feet after the tackle but immediately collapsed.

While there are several potential causes for Hamlin’s cardiac arrest, cardiologists suggested the culprit was a rare phenomenon called commotio cordis.

Damar Hamlin in Orchard Park, New York, in 2021. Joshua Bessex / AP File

In such cases, «there is nothing wrong with the heart,» said Dr. Hari Tandri, director of the cardiac arrhythmia program at Vanderbilt University Medical Center in Nashville, Tennessee. A healthy heart, when struck with blunt force at a specific time, Tandri said, can launch at an abnormal and life-threatening rate.

A spokesman for the American Heart Association, Dr. Comilla Sasson, an emergency physician in Denver, said: «It’s not about how hard the hit was. It’s actually about when the hit happens.»

Normally, the heart pumps oxygen-rich blood throughout the body about every second. There is a rhythm to the process, which keeps the blood flowing at a healthy rate. But every time the heart beats, there is a small moment, less than one-fifth of a second, that makes it vulnerable to the force of a projectile, like a hockey puck or baseball, which can cause chaos and life threatening. heart rate.

It is at this exact moment, experts say, that a hit to the chest in the right place can trigger cardiac arrest in a healthy person. The heart’s electrical system malfunctions and the heart rhythm becomes out of control.

The seconds after such an injury are critical to patient survival, Sasson said.

«For every minute that CPR is not performed, your chances of survival drop by about 10%,» he said. In Hamlin’s case, medical personnel on the sidelines rushed to perform CPR until he was stable enough to be taken away by ambulance for further treatment.

Commotio cordis is thought to occur 15 to 20 times a year in the US, mostly in teens who play sports like baseball, hockey or lacrosse, said Dr. Mark Link, a cardiologist at the University of Texas Southwestern Medical Center. .

It’s even rarer in people older than 20, because the ribs stiffen with age and are better able to protect against blunt trauma, said Link, an expert in commotio cordis and a clinical cardiac electrophysiologist who specializes in heart rhythm problems.

nfl players undergo Health exams, which may include heart scans, to identify potential health problems long before they arrive in the field.

That suggests an underlying heart condition is unlikely to go unnoticed, Mokadam said.

But there are several other reasons why a person can go into cardiac arrest. Sometimes a blood vessel inside the heart muscle swells and bursts.

Mokadam said that’s unlikely to have happened in Hamlin’s case. «If it was a ruptured aneurysm, I would have needed emergency open-heart surgery,» he said. «CPR and an AED won’t fix the problem.» (AED refers to a form of defibrillation therapy.)

Whats Next?

The 24 hours after such an injury are critical, doctors say. Doctors are most likely running a series of tests to make sure there are no underlying heart problems that could have caused Hamlin to collapse or the injuries he sustained after Monday night’s collision. They might include an ultrasound of the heart, a cardiac MRI, and CT scans of the brain.

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