A man who underwent a heart transplant nearly 16 years ago has died of a heart-related illness.

Richard Mueller, 53, died Saturday in Greenfield, Wis. Family members said his heart failed because of blockage of his coronary arteries, the same condition that forced him to seek a transplant in the first place.

Mueller received his heart Nov. 8, 1971, in an operation by renowned heart surgeon Norman Shumway at Stanford University Medical Center in Palo Alto, Calif.

Mueller was the second-longest surviving Stanford heart transplant recipient and one of the longest-living transplant patients in the world, a spokesman for the medical center said.

The spokesman said the longest-surviving heart transplant recipient in the United States is Willem Van Buuren, who received his new heart Jan. 2, 1970.

Mueller was a retired foreman of the Milwaukee Journal-Milwaukee Sentinel's paper and ink department.

"He has been off work for two years, but the other 14 years were very productive," said Mueller's wife, Marilyn. "His doctors said he has really been a fighter for the last two years. They don't know what kept him going."

She said Mueller's heart will be sent to Stanford for tests.