Jason Zhao, 5 years old, received a heart transplant last week at Lucile Packard Children’s Hospital in Palo Alto, which is extraordinary enough. But he also set a North American record by being kept alive for 234 days by an external mechanical pump, known as the Berlin Heart, while waiting for a transplant.


Jason, from Vallejo, Calif., suffered heart failure last June and was put on the Berlin Heart, one of the few pumps small enough to be used to assist infants and children. The device hasn’t been approved yet by the federal Food & Drug Administration but can be used on a case-by-case, waiver basis.


He was the sixth Packard Hospital patient to use the Berlin Heart.


The danger of using the Berlin Heart is that its plastic and metal parts make blood more likely to clot and create complications. But Jason survived clotting and several other life-threatening episodes in the almost eight-month wait, according to Packard Hospital officials.


Then, one month ago, Jason had a stroke and was taken off the transplant list.


"The doctors told us that unless he recovered significantly it was unlikely that he would ever get a transplant," said Jason’s father, Gaughlin Zhao. "At one point we felt that we were at the end of the road, but the doctors and nurses never gave up."


Jason recovered quickly from the stroke, astounding physicians and nurses by recovering speech and movement, and was put back on the transplant list two weeks ago.


Gaughlin Zhao said Dr. David Rosenthal, director of Packard Hospital’s pediatric heart failure program, was so happy "he gave me a big bear hug. Some of the nurses seemed even happier than my wife and I."


Jason’s illness became apparent 18 months ago when he was discovered to have an abnormally large heart. Physicians attempted to treat it with medication but it became apparent in May 2005, before his heart attack, that he would need a new heart.


"We're so glad and sad at the time time," Gaughlin Zhao said. "Without this machine, Jason would have died a long time ago. But in order for him to get a heart another child had to die. It's such a rollercoaster. But we’re so thankful."