The operation, which the hospital claimed was the first of its kind in China, was not disclosed until yesterday.

Operations of this sort were first performed in France and England in the early 1980s, said doctors at Shanghai Children's.

Four days after the operation, Tang was transferred from intensive care to a regular room. The youngster is scheduled to be discharged early next week, doctors said.

"I was so worried prior to the operation because my son is a hemophiliac," said his mother, Chen Fang, 32, a primary-school teacher. "He could die after getting a small cut. But he has suffered much because of his heart disease. Any physical activity leaves him out of breath." The youngster's aorta - the main heart artery - is only one-third the width of a normal aorta in a 7-year-old.

As a result, the boy's cardiac muscle is much thicker, strengthened by having to work harder to pump blood through a narrow artery, doctors said.

Tang's heart problem also slowed his growth; he weighs only 16 kilograms, half the usual weight of a child his age.

Dr. Gu Longjun, one of the youngster's surgeons, said a prerequisite for the operation was controlling Tang's bleeding. "So 18 days before surgery, we began injecting a clotting agent that would stem bleeding," he said.

After spending the first hours of the operation laboring on a procedure to increase the boy's "clotting factor" to 92 percent, the surgical team confronted their primary task: cutting the aorta and stitching in a "patch" to widen the narrow passage.

"The patch is a two-layer article consisting of Tang's own heart tissue inside and man-made bio-material outside," said the lead surgeon, Dr. Liu Jinfen. "A person's own tissue can effectively prevent bleeding, while the biomaterial reinforces the artery since more blood will be flowing through it."

Now, Tang will only have to cope with being a hemophiliac.

(Eastday.com 07/13/2001)