Big Black Christopher Boykin
Christopher "Big Black" Boykin attends the 2014 MTV Movie Awards at Nokia Theatre L.A. Live April 13, 2014 in Los Angeles. He likely died from heart failure. Days before his death, he was hospitalized for heart-related issues, ex-wife Shannon Turley said. Getty Images

“Rob & Big” star Big Black likely died from heart failure Tuesday, TMZ reported the following day. The MTV reality star, whose birth name was Christopher Boykin, was hospitalized in Plano, Texas, days before his death, ex-wife Shannon Turley told the publication. He was 45 years old.

Doctors were afraid Big Black needed a heart transplant since his heart was in bad shape, TMZ reported. He previously had struggled with heart issues and had a defibrillator implanted in his chest.

READ: What Is Big Black’s Cause Of Death? Christopher Boykin Dies At 45 After Rob Dyrdek Reconciliation

The star, who served in the U.S. Navy for 9 years, died Tuesday at 4 p.m. after doctors tried to resuscitate him for 30 minutes. Big Black wasn’t on the implant list yet.

Even though Turley and Big Black divorced in 2009, she took care of him in Texas when his health started to deteriorate. The couple shares 9-year-old daughter Isis.

Turley took to Big Black's Twitter account early Wednesday morning to mourn the death of her ex-husband. “This is Shannon, Big Black's ex-wife, I'm heartbroken to tell you of Black's passing. He's everything to me and Isis and we will miss him,” she wrote. The post was liked more than 15,000 times by his 425,000 followers.

Rob Dyrdek, the professional skater turned MTV host, took to Twitter to mourn his friend. Big Black served as his bodyguard and co-star on “Rob & Big” when it aired for two seasons.

“My heart is broken,” the former skater tweeted Tuesday. “I don't want write this post. I don't want to believe that this is reality. I am so thankful for you. We truly were brothers that lived an unexpected unforgettable adventure. I just can't fathom that it would end so suddenly. You will forever be in my heart.”

Things weren’t always smooth between the two friends. They had a brief falling out in 2008.

“It was a strange period, because both me and him… I had been a pro skateboarder for years, so transitioning into mainstream fame was relatively smooth where for him it was the idea that he was working security two years earlier and now he’s on television. It was a much different dynamic, but I think we both struggled with… I didn’t want to be known as Rob from ‘Rob & Big ,’ and I think he didn’t want to be known as the sidekick. So that created a lot of that tension between me and him,” Dyrdek explained, according to People Magazine.

“I think it was more the fundamental struggle of wanting to not be so connected to each other,” Dyrdek added. “Ultimately, after we had a big blowout creatively over an idea … things were so tense at certain times — it’s funny now that I think about it — but we literally would film some of the funniest things that we have ever done and would be losing it and then walk away and not talk to each other. It was super, super bizarre.”

READ: Big Black’s Ex-Wife Shannon Breaks Silence

The friends ultimately reconciled, with Big Black posted a throwback picture to Instagram six weeks ago. “The Team… Meaty, Mini G, Rob&Big Legendary....Rob&Big 06-08,” he wrote.

An official cause of death was not revealed.

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