Dr. Willem Johan Kolff, the former University of Utah medical pioneer who invented kidney dialysis and helped design the first artificial heart to be used in a human, died Wednesday in a Philadelphia care center of causes incident to age, family members said. He was 97.

Known in medical circles as "the father of artificial organs," many Utahns remember Dr. Kolff as one of a team of surgeons who made headlines worldwide when they implanted the artificial heart into Seattle dentist Barney Clark at University Hospital in 1982.

Clark lived for four months, then died with the heart still functioning. The feat put the U. at the forefront of artificial organ research and made Dr. Kolff and his team international medical celebrities.

The scope of Dr. Kolff's medical accomplishments included rigging the prototype for what would become the world's first kidney dialysis machine from sausage casings and an automobile water pump part as a young doctor in the Nazi-occupied Netherlands during World War II. His work eventually grew in scope and size to include bits of the artificial heart, artificial sight, artificial kidneys and placentas, and the wearable artificial lung.

Dr. Kolff published numerous books, more than 600 papers and articles, was inducted into the Inventors' Hall of Fame in 1985 and received hundreds of awards during his lifetime. In 1990, Life Magazine named him one of the 100 most important Americans of the 20th century.

In September 2002, Dr. Kolff received the Albert Lasker Award for Clinical Medical Research — considered to be the highest honor in American medicine — for his development of kidney dialysis. The nominating committee noted the invention "changed kidney failure from a fatal to a treatable disease, prolonging the useful lives of millions of patients."

Born Feb. 14, 1911, in The Netherlands, Dr. Kolff moved with his wife, Janke, and their five children to the United States in 1950. He became a U.S. citizen in 1956. He earned an M.D. at the University of Leyden Medical School in Holland, a Ph.D. (summa cum laude) at the University of Groningen, Holland, and received several honorary medical degrees.

Dr. Kolff began work on the artificial kidney in 1939, developing the rotating drum kidney in 1941, which led to the 1955 twin-coil kidney, providing the possibility of the first dialysis for kidney patients worldwide.

He began work on heart-lung machines in 1948, and the first membrane oxygenators were used successfully in patients in 1955.