An 11-year-old boy recently became the first person in the world to have an artificial heart valve replaced with a living donor heart valve.
Preston Porter, who has lived for the past near-decade with a mechanical mitral valve, underwent replacement of the artificial valve with a living donor mitral valve through a partial heart transplant surgery on April 27.
Preston received a mechanical mitral valve when he was 1, after doctors discovered he had a heart defect when he was hospitalized with a virus at 20 months old.
Those with a failing or infected valve may undergo open heart surgery to replace the defective valve with a mechanical valve made from durable material or bio-prosthetic valve from a cadaver or an animal like a pig or cow.
Woman speaks out after receiving gene-edited pig kidney transplantFollowing his first operation, for almost a decade, Preston has needed to take a blood-thinning medication to help prevent blood clots on his mechanical valve. This blood thinner increases the risk of bleeding and only works within certain therapeutic ranges, so Preston has had to undergo weekly blood tests, limit intake of certain foods that interact with the blood thinner, and avoid sports, according to his mom.
"He's a very active kid. You know, over the years he's missed out on a lot," Lauren Porter told "Good Morning America."
Aside from the blood thinner and the food and fitness restrictions, having a mechanical valve also meant Preston would need multiple open-heart surgeries to switch out the valve over the course of his lifetime.
In January, he and his family learned he was outgrowing his mechanical valve. Doctors suggested then that a partial heart transplant, which would take a valve from a donor heart to replace the mechanical one, could be an option for him.
"My initial reaction was, no, this is too new. There's no data," Porter recalled to "GMA."
But having a donor valve could mean Preston could get off the blood thinner that kept him from being active.
"When we first told him that this was an option, he said, 'So this means I could be a normal kid,'" Porter said.
"It just seemed different," Preston added.
4-year-old who received new heart after waiting 1,025 days goes home from hospitalPreston and his family eventually agreed to the partial transplant surgery, which was performed at Children's National Hospital in Washington, D.C.
Dr. Yves d'Udekem, the chief of cardiac surgery at Children's National Hospital, who performed Preston's surgery, said in a statement he was "honored" Preston and his family entrusted his care to the team at Children's National.
D'Udekem told "GMA" the breakthrough surgery meant Preston's new donor valve could grow with him.
"It's living so it can grow with him," d'Udekem explained. "He's barely a bit more than 60 pounds, so it can grow double his weight and that should grow with him. It's a natural tissue. It can heal itself."
Following the surgery, Preston will have to continue with a low-dose of anti-rejection medications, but he can now be an active kid.
Preston said he is looking forward to playing flag football.
"It feels great ... It also feels really cool knowing I can also help people in the future."
Dr. Jennifer Miao, a board-certified cardiologist and critical care fellow at Yale School of Medicine/YNHH and a member of the ABC News Medical Unit, contributed to this story.
