STUDIO CITY, CA - MAY 19: MMA fighter Kimbo Slice demonstrates MMA fighter techniques at CBS's "Elite XC Saturday Night Fights" Press Conference at CBS Radford Studios on May 19, 2008 in Studio City, California. (Photo by Stephen Shugerman/Getty Images)

The details about Kimbo Slice's health before his passing are disturbing

How does something like this happen?

Kimbo Slice had a professional mixed martial arts bout not too long ago, as he fought for the Bellator MMA promotion against Dada 5000 back in February. Slice was expected to fight again soon, too, as he was scheduled for a July fight in London against James Thompson.

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However, Slice passed away on Monday, and his death has really left one major question: how did a 42 year old man — who was an active fighter — pass away so suddenly? Well, it appears we have some answers, and they are pretty disturbing to think about.

According to the Sun Sentinel, Slice — real name Kevin Ferguson — was rushed to the hospital on Friday, and was scheduled to be transported to Cleveland to await a heart transplant.

Pro wrestling and MMA journalist Dave Meltzer had some more information on the condition of Slice's heart in his most recent edition of the Wrestling Observer Newsletter. (subscription required) Meltzer reports that Slice's heart was functioning at only ten percent of expected capacity, and that a seizure and heart attack is what ultimately led to his death.

Later, doctor's informed Slice's family that his heart was working at only ten percent of its capacity and he would need a heart transplant.

A source inside the hospital stated that they believed he had a seizure when he was being fitted for a life vest, which monitors the heart rate to check for irregularities. He is believed to have died while they were fitting it, and they worked on him for a full hour trying to revive him, going through two crash carts.

All of that sounds awful, and it is definitely not something you would see coming for an active, professional fighter.

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Meltzer also reported on Thursday's episode of Wrestling Observer Radio that Slice was heavily screened by Bellator and the Texas regulatory commissions before his February fight. Slice — and Dada 5000 for that matter, who nearly died after that fight — passed all of those tests, meaning full clearance to fight without any issue.

That is what makes this so disturbing. Slice was cleared to fight just a few months ago, and was scheduled to have another fight a month from now. Guys like that usually don't end up at the hospital with heart failure.

Maybe past PED use is to blame, and maybe Slice shouldn't have been fighting at the age of 42 regardless of his health. However, Slice's unfortunate death leaves the MMA world with some questions to consider, as one thing is clear: this shouldn't have happened to a 42 year old active athlete.