On Feb. 24, Analiah Duarte turned 1.

She celebrated with a visit to Magic Kingdom to see Mickey Mouse – her favorite Disney character.

She is so enamored with the big-eared mouse clad in red shorts that as soon as she hears his name, she points to pictures of him on a helium balloon in her living room. When Mickey sings on TV, she dances and brings smiles to her mother, Johana Duarte.

One year ago, there were no smiles in the Duarte home.

Analiah was born with Ebsten’s Anomaly, a rare congenital heart defect where a malfunctioning valve causes blood to flow backward into the right atrium of the heart, and flow less toward the lungs. It affects one in 200,000 U.S. births and is considered an “extremely lethal heart defect,” said Dr. Redmond Burke, chief of cardiovascular surgery at Miami Children’s Hospital.

Because of the reverse flow, blood had backed up in Analiah’s right atrium, forcing her heart to grow and take up nearly her entire chest, squeezing her lungs. The condition is known as having a wall-to-wall heart.

Burke still remembers the day he and other surgeons saw an X-ray of Analiah’s heart for the first time.

“You could look around the room and see everyone put their head down because everyone knew that’s as about a lethal heart defect as there is,” he said.

Perhaps it was fate, an answer to Analiah’s mother’s prayers or both. Miami Children’s doctors, led by Burke, found an answer to fix the baby’s heart.

Medical-biomaterial-company CorMatrix Cardiovascular, based in Georgia, had developed an extracellular matrix material, a collagen framework that cells could attach to and hold the organs together. It has the structure, shape and signaling properties to attract stem cells, said Burke.

“If you put this sub-mucosal tissue anywhere in the body, it functions like a fisherman’s net,” said Burke. “It captures stem cells flowing through the bloodstream right where you want them. It’s like having the framework of a house that can actually recruit all the bricks and wood need to create a perfect house.”

The stem cells captured by the matrix morph into the tissue needed for the malfunctioning organ – in this case the heart’s tricuspid valve – to work properly.

While doctors had previously used the material to promote natural growth of human organs, Burke was the first to use the material to fashion a baby’s heart valve.

“I thought, ‘What if I could put something in her that worked like a valve but over time it would start capturing stem cells so that she can rebuild her valve,’ ” said Burke. “That would be the holy grail of heart surgery.”

One year later, Analiah is a medical miracle – the first child with such a valve.

The valve he fashioned, made from the sub-mucosal lining of a pig’s intestine, is a one-way valve where blood flows in the right direction.

Sewed in the place where the tricuspid valve would have been, the valve Burke made was anchored at two points: at its opening and a slit on the other side that allowed the blood to flow into the right ventricle. When the right ventricle contracts, the slit closes and blood is forced out the pulmonary valve.

Based on their research, doctors think that over time the stem cells the matrix captures will help Analiah rebuild her own valve. That would eliminate the need for follow-up surgeries usually, needed for children with an implanted valve. As a patient’s heart grow, surgeons need to replace the implanted valves with bigger ones.