C. Walton Lillehei, 80, who was regarded as the father of open-heart surgery and trained hundreds of other surgeons, including Christiaan Barnard, died of cancer July 5 in St. Paul.

Dr. Lillehei created many innovative heart surgery techniques while teaching at the University of Minnesota during the 1950s. He later headed the surgery department at Cornell Medical Center-New York Hospital.

On Sept. 2, 1952, Dr. Lillehei and 5-year-old Jackie Johnson--who suffered from a life-threatening heart defect--made medical history when Jackie became the first person to successfully undergo open-heart surgery.

Before then, repairs were impossible because doctors lacked the ability to stop circulation safely so they could work inside the heart.

Surgeons took 19 hours to lower the child's body temperature 17 degrees, wrapping her in rubber blankets that conducted a cold alcohol solution. They cut off all blood flow in her body for 5 1/2 minutes while they worked inside the heart.

"Last year, 500,000 open-heart operations were done worldwide," Dr. Lillehei said at a 1987 reunion with his patient, by then known as Jackie Johnson Weeks. "That's about 2,000 a day."

In 1955, Dr. Lillehei led researchers in developing a machine to oxygenate blood and pump it through the patient's body, making open-heart surgery easier and ultimately making heart-transplant surgery possible.

Dr. Lillehei's pupil Barnard gained worldwide fame when he performed the first human heart transplant in 1967 in South Africa.

"Chris generously admits that I taught him everything he knows about cardiac surgery," Dr. Lillehei once quipped. "I have to remind him periodically that I haven't taught him everything I know."

In 1957, Dr. Lillehei worked with Medtronic Inc. co-founder Earl Bakken to develop the first wearable pacemaker for patients with chronic complete heart block. He also contributed to the design of four artificial heart valves, including the widely used St. Jude Medical Mechanical Heart Valve.

"The world doesn't have enough heroes today, and I hope in his death people recognize him that way," said Medtronic Vice Chairman Glen Nelson, another former student of Dr. Lillehei's.

In 1973, Dr. Lillehei's image was tarnished when he was found guilty of tax evasion. He was fined $50,000 and ordered to complete six months of community service.

A few months later, at age 55, he had to give up surgery when he developed cataracts, losing the keen eyesight needed for such meticulous work. He turned to writing and administration, continuing to lecture on open-heart surgery.

Survivors include his wife, Kaye, and three children.