A grant from a charitable foundation has flown the surgeons to Moscow where they will operate on five children, CBS News Correspondent David Hawkins reports.
Many of the babies need help desperately. One girl's heart has a hole in it and only one valve where there should be two.
"She is weak," says her mother. "And she has stopped growing. I just want her to be okay."
The doctors from California have chosen her as their first case.
It's too late, though, for another one-year-old boy. Not long ago he was saying "mama" and "papa." Now he rarely even opens his eyes.
"It seems to me he has no reaction," his mother says.
The doctors already operated on the boy, but something went wrong. They told the mother there is nothing more they can do. She should take her son home to die.
"I can't agree with our doctor's decision," she says.
But the Americans can't help -- he suffered irreversible brain damage from the operation. It's a sad story that is too often repeated here.
Each year about 50,000 Russian children are born with heart defects, but in all of Russia there are only two hospitals that can treat them. One doctor says his department can do just 200 heart operation a year.
"The state has no money," he complains.
Without surgery, 70 percent of the children will die before their first birthday. If they had been born in the United States, their chance of survival would be 95 percent.
There are some problems the American doctors can't possibly fix. There are shortages of equipment, medicine, and even ordinary supplies. Russia's doctors know what needs to be done to help the children but they lack the resources and experience to do it.
For the surgeons on the UCLA team, these heart operations are fairly routine. By watching the Americans at work, the Russian doctors learn the latest procedures and techniques.
"I think it's an opportunity for them to see how we do things," an American doctor explains.
After five hours of delicate surgery, there is good news for one girl and her mother.
"Everything is okay," the doctor says. "She should have a relatively normal heart."
"We never dreamed that American doctors would do the operation," says her mother. "We were lucky. Two heads are better than one."
Together the Russian and American doctors saved five little souls this time. That's five happy endings among so many broken hearts.