The younger brother, Le Le, who was heavier received a 14-year-old child's donor heart on July 29. He now can breathe on his own without a ventilator.

Dong Nianguo, who was in charge of the surgeries, said pediatric heart transplantation is usually done to treat cardiomyopathy and congenital heart disease.

"A heart transplantation on a child can usually have a better result than on an adult," Wang said.

However, the shortage of donors now is the biggest limitation for the development of pediatric heart transplantation. At least 17 percent of children who need a transplant die while waiting for a donor.

Jiang Peijin in Beijing contributed to the story.