Angela Irizarry was born with only one pumping heart chamber. In August, doctors at Yale University performed experimental surgery to grow a new vessel by implanting a bioabsorbable tube in Angela's chest. 

The tube had cells in it, including stem cells from Angela's bone marrow. Doctors say the tube has disappeared and left a conduit that acts like a normal blood vessel.

"We're making a blood vessel where there wasn't one," said Christopher Breuer, the surgeon who implanted the device.  "We're inducing regeneration," he told the Wall Street Journal. 

Angela's condition, hypoplastic left heart syndrome, affects more than 3,000 new born children in the Unite States every year and is normally treated by multiple surgeries that enables the child to function with the ventricle missing. Approximately 70% don't live to see their first birthdays, said Dr. Breuer.

Regenerative growth was thought impossible for humans but stem-cell research and tissue engineering have recently shown that, if placed correctly, they could possibly "reawaken" the developmental forces thought to be lost at birth.

The procedure took four years of labratory research beginning at Yale in 2003. In 2007 Dr. Breuer asked the Food and Drug Administration to test on patients. It was another four years before he got the approval. A similar approach was studied on 25 children and adults in Japan a decade ago.