AURORA, Colo. — Five-year-old Ollie Wagner was born with a congenital heart disease called hypoplastic left heart syndrome, requiring three surgeries before the age of 3.
"Roughly six months after his third surgery, he was just a little over two. He went into heart failure. His heart failure progressed very rapidly," his mother, Sarah Mackey, said.
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Ollie was placed on the transplant list and received a ventricular assist device or VAD — a mechanical device that helps a weakened heart circulate blood throughout the body.
His early recovery was far from smooth.
"He was extremely sick for a pretty prolonged period after his VAD. The first two and a half months of Ollie's course were fraught with a really complicated course," Rob Hyslop, a nurse and VAD coordinator at Children's Hospital Colorado, said.

Then, something shifted.
"Like a little switch went off in him and he finally stabilized… and then we just waited… and he got stronger and just kind of lived his life the best he could, waiting," Mackey said.
He waited 419 days for his hero heart.
Ollie's father, Anthony Wagner, said the moment the transplant team accepted an offer felt surreal.
"I didn't believe it at first. I was like, there's no way. Is this really happening? And pinch me, I'm dreaming," Wagner said.
Now, a year and a half after his transplant, Ollie is back at one of his favorite places — the hospital dog park — showing off the joyful personality that left a lasting mark on the staff who cared for him.
"There's a number of people throughout the hospital that still talk about Ollie, and so I think that's a reflection of how much he touched all of our lives," Hyslop said.

Hyslop, who spent hundreds of hours with Ollie during his stay, said the bond they formed went both ways.
"He became a little bit of an emotional support crutch. It was almost as much that we were taking care of Ollie, but Ollie was taking care of us at the same time,” Hyslop said.
When Ollie's family told him he would be visiting the hospital, his reaction said it all.
"Today it was, 'You're gonna see your Rob,' and he's like, 'Oh, okay, let's go. Yeah, we're gonna go see them, and I'm gonna be able to come back home. I don't have to stay there,'" Wagner said.
His parents said he is a different child today than the one who spent more than a year fighting for his life inside those walls.
"He's the strongest little person I know," Wagner and Mackey said.
This story was reported on-air by a journalist and has been converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.
