Ronnie “Roc” Walker, a 1978 UM Hurricane football defensive end tackle, is another success story. Walker had a heart transplant in May 2010 about five months after being fitted with a ventricular assist device. “Physically, I feel as strong as I was when I played football at the UM and I’m 57,” he said from his home in Miramar.

At 17, a doctor told him he had an irregular heartbeat. “It didn’t mean anything to me. It didn’t stop me from playing football. I just assumed it was status quo,” said Walker, who works in corporate security.

But about 10 years ago Walker realized something was wrong when he was so exhausted he could barely walk. His symptoms worsened. He suffered from sexual dysfunction, couldn’t brush his teeth, and even chewing became too much of an effort. His kidneys and liver began to shut down and his breathing grew labored.

Walker’s first stop was the church, then the hospital where, ultimately, he met Pham and had his life-saving surgery.

“I’m going to get to the church and get it right with God first. I was sensing some impending doom there,” he recalled. “I went to the hospital and they gave me an X-ray and said, ‘You got a really big heart’ — and I said, ‘That’s what people tell me.’ ”

But it was no joking matter.

In January 2010 Walker was fitted with the VAD. “Once I got that device, I was pretty good to go. That was a bridge to the transplant,” he said. When a heart became available, Walker struggled with guilt.

“I got pretty accustomed to this mechanical device and it gave me time to reflect that someone will have to die for me to live. I couldn’t wrap my brain around that idea. I don’t deserve for anyone to die for me to live.”

Post-surgery, Walker talked to the donor’s mother and thanked her for her son’s heart. He wanted to know about the young man.

“She said, ‘Mr. Walker, though he was only 19, he loved animals and he loved people. I recall once giving him money to go shopping and he didn’t buy anything. I asked him why and he said, ‘Mommy, I saw someone who needed it more.’ ”

“I couldn’t hold back the tears. It hit me like a ton of bricks,” Walker said. “It made me realize I had a tremendous responsibility to live a life that was exemplary of the type of young man his mother told me about.”

F ollow @HowardCohen on Twitter.