- Open heart surgery can be scary, especially when the heart is this small.

You see, this is the size of a newborn's heart.

For babies born with heart issues, sometimes their only option is a full heart transplant, which is risky, but surgeons at Duke University Hospital have discovered an alternative.

It's called a partial heart transplant.

It's saving newborn lives and has the potential to revolutionize healthcare.

[dramatic music] Lorna Duncan Soderbloom wasn't sure what motherhood would bring, but raising her oldest son, Waylon, made having a second child an easy decision.

- So when I got pregnant with our second child, I was super excited 'cause I'm like, I know what I'm doing this time, like we're good to go.

- [David] But at the 20 week anatomy scan, doctors discovered a heart problem.

They thought it was a heart defect called Tetrology of Fallot.

But when Kix Soderbloom was born, doctors said it was actually an even less common heart defect called truncus arteriosis.

- At first, it made me really scared 'cause I had no idea what it was.

- [David] Infants born with this condition have only one blood vessel out of the heart instead of the usual two.

It's a life-threatening condition, and there are only about 250 cases per year in the United States.

- Basically, instead of having an artery to the lungs and then an artery to the body, they're born with a single artery that then splits to the lungs and the body.

- [David] Kix's case was so severe, doctors believed there was no time for more traditional surgery.

- Unfortunately, the child was so sick that we knew we weren't gonna get a heart transplant, a real heart transplant.

Those take about six months in this age group to get.

- [David] So doctors proposed a brand new treatment called a partial heart transplant.

With this procedure, doctors take the living tissue of an unused donor heart, put it in the newborn's heart and the tissue heals the heart and grows with the child.

Duke surgeons had only done this procedure once before, and that was the first time it had ever been performed.

- They were basically like, we want to do the partial heart transplant, and it was raining outside, it felt like a movie, and I was just like, is this my life?

I'm looking around at all these people.

I'm like, this has been done one time and we're gonna be the second, And it was just, it was the craziest experience I've ever experienced in my life.

- [Nurse] Daddy?

- [Dad] Yes.

- [David] This baby is Owen Monroe.

He received the world's first partial heart transplant at Duke University Hospital.

He also had a severe form of truncus arteriosis.

- And I just remember getting in in the truck after that ultrasound and just, I think we just cried.

- We had the conversation of, I hope we don't have to plan a funeral in a few weeks.

[gentle music] - [David] Doctors at Duke told the Monroe family that the procedure had only been done on pigs, but they were confident it was the best option for Owen.

- I was at the point where I said just do whatever you have to do to save him.

[nurse laughing] - [David] The procedure was a success, and now, Owen is doing remarkably well.

He's met all his developmental milestones since coming home from Duke.

- It's really, truly amazing, just that we could be a small part of potentially changing history, it's not something that's easily comprehendible.

We're just a mom and dad who wanted to have a baby, and here we are.

- [David] Seeing Owen's progress helped the Soderbloom family with their decision to get the procedure for Kix.

- I wish everyone could not experience the heartache and the pain that goes through it, but just experience a glimpse of it so other people would know how life is really such a gift.

[Kix babbling] - [David] And Kix's partial heart transplant was also a success.

He's had to stay at the hospital a little longer due to other birth defects, but this procedure is giving the Soderbloom family a chance to soon take their newborn home.

- And heart surgery is not your everyday subject for a lot of people.

And if it can limit the amount of surgeries, that would be truly amazing, and it's just awesome to be a part of it.

'cause I never in my life thought I was gonna be a part of something like this.

- Every once in a while, there's a new innovation that comes out, and right now, this I think is it, I'm getting emails constantly about people asking how we pulled this off.

- Now here's our result after the partial heart transplant, - [David] Dr. Turik and Dr. Carboni say this procedure could be used for all sorts of heart conditions.

They say it could very well be a regular operation in the future.

- And introducing this into the field is a great feeling, but watching this scale and watching this multiply and watching more and more folks and other centers be able to do this work, I think that's what I'm really excited about.

I'm excited that we can bring this almost to the mainstream.

- Yeah.

And then today- - [David] Nothing could have prepared Soderbloom for what she and her family have gone through, but she's excited to hopefully soon take her baby home, and she's optimistic about the path her son has helped pave for other families in the future.

- It's just amazing just to see this little child be able to go through all of this and come out on top.

I'm proud to be his mom, for sure.

[gentle music] - And doctors say one of the benefits of this procedure is that it uses tissue from an unused donor heart.

That means a heart that may have been thrown away can now be used to potentially save a child's life.

Thanks for watching.

We'll see you next time.

[gentle music]