Italian doctor Antonio Amodeo shows the prototype of artificial heart that saved the life of a 16-month-old baby boy. (Image credit: Alessandro Di Meo/EPA)

An artificial heart the size of a pinky finger kept a 16-month-old baby alive for nearly two weeks while he waited for a heart transplant.

The Italian baby, whose name has not been released, had dilated cardiomyopathy, a disease that stretched the muscular walls of his heart so thin they could no longer contract to pump blood. He needed a transplant. But without a suitable donor on the horizon, doctors had to improvise.

"This patient, he was a mascot for us," said surgeon Antonio Amodeo of Rome's Bambino Gesu Hospital, explaining how the baby had been in the hospital's intensive care unit since he was one month old. "I said, 'He cannot die; I have to do something for him.'"

Amodeo and his team had already tried a Berlin Heart, a scaled-down version of the left ventricular assist device once worn by former Vice President Dick Cheney. But the device, with its tubes that run outside the body, triggered a risky infection. So they turned to a tiny, 11-gram implantable pump invented by American entrepreneur Dr. Robert Jarvik that had only been tested on animals.

"I said, 'Dr, Jarvik, please help me. I don't want to lose this patient," Amodeo said, adding that the hospital needed special permission from from the U.S. Food and Drug Administration and the Italian Ministry of Health before proceeding with the unapproved device. "We knew there were only a few animal experiments, but we knew it could probably work."

And it did work, keeping the baby alive for 13 days before electrical problems forced the doctors to switch back to the Berlin Heart. Two days later, a donor heart became available.

"It's incredible," said Amodeo, adding that the transplant, which took place in April, was successful and the baby will be discharged any day now. "We are all extremely happy because the little boy will be in his mother's hands. He's going to be fine."