One of the first children to survive open-heart surgery 46 years ago is now waiting for a life-saving heart transplant.

Johnny Watson was a sickly 7-year-old with a large hole between the lower chambers of his heart when he underwent the pioneering surgery in 1955 at University of Minnesota hospital, now Fairview-University Medical Center.

A team of doctors led by Dr. C. Walton Lillehei opened the boy's chest, hooked his circulatory system to a new device called a bubble oxygenator, cut open his heart and closed the hole with a few sutures.

"Two weeks later, I hit the sidewalk and never slowed down until about five years ago," said Watson, who is now 53 and lives in Arden Hills.

Before the early 1950s, infants born with a hole between the chambers of their hearts faced certain death.

Almost a half-century after the surgery, doctors don't know why Watson's heart suddenly began to fail. Watson said they suspect it may have been triggered partly by severe bouts of rapid heartbeat he suffered before the hole in the heart was repaired.

Now Watson is back at the same hospital awaiting a new heart. Doctors have implanted two pumps -- one that moves blood through his body and one that moves blood through his lungs -- that are keeping him alive until a suitable donor organ can be found.

In the 1950s, surgeons knew how to fix defects on the outside of the heart, but most thought it was impossible to cut open a beating heart and fix it before patient died from lack of blood.

Lillehei, working on dogs, discovered it was possible to connect two animals' circulatory systems, tie off the blood flow to one heart and fix it while the other dog's heart and lungs provided oxygenated blood to both animals.

After repeated tests on dogs, Lillehei used the procedure in March 1954 to repair a hole in the heart of a 1-year-old boy. Blood from the boy's father kept him alive, but the toddler died less than two weeks later.

Lillehei tried again, weathering criticism for deaths that ensued.

A colleague, Dr. Richard DeWall, took up the challenge and built the forerunner of today's heart-lung bypass machine out of some tubing, a few corks and 18 hypodermic needles.

By May 1955, Lillehei was ready to try it on humans. Two patients died, but then five others, including Watson, were operated on and all survived.

For three years after the operation, Watson and his parents lived in Minnesota to be near the hospital.

Watson returned to the state in 1970.

"That's where I felt safest for my health," he said. "Not only is the air cleaner and cooler, I also have the security blanket of the doctors at the University of Minnesota. I knew that if I ever became sick, it would be my heart. ... They treat me like a king here, and I don't deserve it."