The Japanese boy, Hiroki Ando, who had to go to the US for a heart transplant, was finally able to receive one on July 2, and seems to be doing well according to his diary in his mother's blog (in Japanese) and has left the hospital for outpatient "rehabilitation" in New York.
A law revising the age for organ transplants was passed recently, so the need for Japanese children to go overseas for such care may slowly decrease.