Baby Born With Heart Outside Chest Now Doing Well, Despite Grim Outlook

"I had agreed not to hold her so she could go straight to the surgery," said Caitlin Veitz, who first heard her daughter's diagnosis during an ultrasound.

Doctors originally did not believe little Kieran, who is now 18 months old and doing well, would make it after they realized she would be born with her heart growing outside of her chest.

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Caitlin and Brian Veitz of Mandan, North Dakota, received the devastating news during a routine ultrasound, when she was only 20 weeks pregnant.

"He showed us the silhouette of the lungs, and where the heart would normally sit," Caitlin told Barcroft Media. "And then he pointed three inches to the left, and showed us where her heart had grown. That's when I said it out loud: 'Her heart had grown outside of her chest.'"

Doctors said her baby had ectopia cordis, a rare congenital heart defect that affects one in 100,000 babies.

Caitlin and Brian were then told that if their baby made it to birth, she would have a 90 percent chance of dying within three days of being born, and a 95 percent chance of dying within a week.

"We knew the odds were stacked against her," Caitlin said. But, the couple remained positive.

To give their baby the best chance, they traveled to the Mayo Clinic in Rochester, Minnesota, where doctors prepared for surgery by using fetal MRI images to create a 3D model of Kieran, including what she would look like when she was born and where her organs would be located, for the first time in medical history

Within an hour-and-a-half of Caitlin's emergency C-section, 60 doctors prepared to operate on the newborn.

"I had agreed not to hold her so that she could go straight to the surgery," Caitlin said, not expecting her baby to survive. "That was maybe one of the hardest things. I heard this little cry and it was very sweet. Bittersweet."

For the next five hours, doctors worked meticulously to place little Kieran's heart back inside her ribcage.

Miraculously, little Kieran survived the surgery, but she was not yet out of the woods.

Her mom was able to hold her child for the first time when she was a week old. For the first four months, Kieran remained in the intensive care unit.

When she became old enough to go home — located more than 500 miles from the hospital — the Mayo Clinic arranged a private plane to fly her and all her medical equipment to North Dakota.

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At 18 months old, doctors are now very optimistic about little Kieran's progress, even though she will need several more surgeries in her lifetime.

Because her lungs were displaced during the surgery, she continues to have a breathing tube fitted in her throat. She also eats through a feeding tube.

Kieran has since started working with a specialist to catch up with other children her age, including eating with her mouth, walking, and even talking.

Watch: Baby Born for a Second Time After Surgeons Operated on Her While Still in Mother's Womb