An Arizona baby born prematurely and with a life-threatening heart condition successfully underwent a heart transplant when he was just 6 days old, and is continuing to recover after doctors initially told his parents he may not survive birth.

Doctors first noticed something was amiss during Caylyn Otto’s 20 week prenatal exam, The Arizona Republic reported. She was put in the care of pediatric cardiologist Dr. Christopher Lindblade at Phoenix Children’s Hospital, who was shocked at the size of the fetus’ heart.

“The left ventricle was huge for a 24-week-old,” Lindblade told The Arizona Republic. “It was massive.”

The formal diagnosis was dilated cardiomyopathy. Doctors told Otto and the baby's father Chris Crawford that their child may be born stillborn, and if he made it through delivery he would likely need a heart transplant.

During the second screening, the couple was told that their son’s heart had enlarged to seven times the size of a 28-week-old fetus’ left ventricle, The Arizona Republic reported.

As doctors told them to prepare for the worst, they removed all baby supplies from their home.

“It was too hard for me to look at all that stuff,” Otto told the newspaper. Hospice workers asked the couple if they wanted to hold their baby, should he be stillborn.

Otto was told that her son would have the best chance of survival if he made it to a 36-week delivery, but she went into labor when she was 33 weeks pregnant.

“When her water broke, she woke up screaming,” Lindblade told The Arizona Republic. Doctors delivered baby Oliver Hope a few days later on Jan. 5, and the Ottos heard their boy’s first cry. By Jan. 9, doctors placed Oliver on the transplant waiting list, and a few days later he was matched with an unidentified donor and taken into surgery.

Though his lungs are too weak for him to be taken home and doctors aren’t sure how long it will be until he is released, his body hasn’t rejected the heart, the report said.

The new parents held a baby shower for him, and brought his infant car seat to his hospital room.

“He’s coming home,” Otto told The Arizona Republic.

Doctors at Phoenix Children’s Hospital believe Oliver is one of the youngest patients to ever receive a heart transplant.

“I do feel there was something miraculous that happened with this child,” Lindblade told The Arizona Republic.

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