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Bills safety Damar Hamlin suffered cardiac arrest after a tackle in Monday night's game against the Bengals, prompting the NFL to indefinitely suspend and postpone the matchup. The 24-year-old Pittsburgh product was administered CPR and had his heartbeat restored before being transported to the University of Cincinnati Medical Center. He has been sedated and stabilized in the hospital's intensive care unit since late Monday, the Bills announced, while listed in critical condition.

For more insight on Hamlin's injury, potential recovery and other factors related to Monday's traumatic incident, CBS Sports spoke with Dr. Aaron Baggish, of Mass General Brigham sports cardiology. A team cardiologist for the Patriots, Harvard University Athletics, U.S. Soccer and other organizations, Baggish is the director of the cardiovascular performance program at Massachusetts General Hospital Heart Center, and also serves as medical director for the Boston Marathon.

The following interview has been edited for content and clarity.

What was your initial reaction and assessment when watching the play that left Damar Hamlin injured Monday?

Dr. Baggish: When I saw what had happened, the type of collapse he had, where his body went completely limp, is the type of collapse that has a very, very high likelihood of the heart stopping. That's a really concerning thing. The real good-news story is how promptly the medical team on the sideline was at his side performing resuscitation. That is not always the case.

How much did the quick response by the medical teams affect Hamlin's diagnosis?

Dr. Baggish: Well, the diagnosis, which refers to the reason the cardiac arrest happened, is still unclear. But when something like this happens, the heart stops pumping blood, and one of the 100-percent certainties, if resuscitation isn't done, is automatic death. So it was imperative they responded so quickly.

From your perspective, what are the possible causes of Hamlin's cardiac arrest?

Dr. Baggish: There's a long list: there are genetic and congenital abnormalities which could be at play, I know there's been speculation about the blunt force from the tackle, but I would say that it's really premature to make any speculation. In fact, to jump to a conclusion would be a mistake. The diagnosis of commotio cordis, for example [which refers to a fatal disruption of the heart rhythm from a blow to the chest], is what we call a diagnosis of exclusion, meaning other things have been eliminated. We would never conclude that unless other factors have been ruled out.

Are there potential causes that you deem more likely in this case?

Dr. Baggish: It would be irresponsible to attach any kind of diagnosis until we're sure. The majority of cardiac arrests that occur in young athletes occur because of some genetic heart condition. That is independent of getting a blow to the chest. This is why, to come up with a short list is really not possible.

Generally how long does it take to diagnose the actual cause?

Dr. Baggish: The usual sequence would be to first get him stable, and I can't comment on the timeframe without being at his bedside. But the diagnostic part of this is usually second in line.

From the outside, then, what happens next?

Dr. Baggish: I think one of the things that can start now is to watch how the resuscitation effort was conducted and to learn from that. It was an exceptionally effective resuscitation effort. And it speaks to the planning that goes into it. They rehearse for emergencies like this. They have to be ready. ... With each day, the athlete's status will be updated, and the recovery trajectory will probably depend a lot on the next 48-72 hours.

If the blow to the chest is, in fact, ruled the cause, how common is such an occurrence?

Dr. Baggish: If this ends up being commotio cordis, this is not the first time it's happened, though it's not been a (common) style of sudden death in football compared with ball sports like lacrosse and baseball, or hockey, a puck sport. This would not be the first time it's happened in sports, certainly. But I want to be clear that I'm not saying that is the diagnosis at this point.

Aside from your medical profession, as a fan, what are your hopes and expectations moving forward?

Dr. Baggish: The only thing I can say I hope this does is reinforce medical teams that they need to be ready for unexpected catastrophe. I don't anticipate and wouldn't be the right person to suggest any policy change or additional changes in the way the sport is played. But I hope it's not a knee-jerk reaction if that's the case, because oftentimes it's worse to change policies in knee-jerk fashion based on one problem. ... First and foremost, of course, my hope is the young man recovers fully. And as a fan who also happens to be a doctor, I'm cognizant of the risk these athletes assume when they decide to play these sports, and I support their decisions to do so, but it's always sad when something like this occurs.