According to Thüringer Allgemeine, Gauder was on dialysis for a few months after suffering kidney failure, with a planned transplant not occurring before he died.

At the Moscow 1980 Olympics, Gauder won the 50 kilometre walk by nearly two minutes when he competed for East Germany, and he would win bronze at Seoul 1988.

He was also the World Championships gold medallist in Rome in the same event in 1987, a year after he achieved the same feat at the 1986 European Championships in Stuttgart.

Later, representing the unified Germany, he would finish third at the 1991 Tokyo World Championships and he also won bronze at the 1990 European Championships in Split in Croatia.

This was not the first time Gauder had issues with his heart, as he previously suffered a virus infection in 1996 at 41-years-old.

After living with an artificial heart for several months, he received a heart transplant.

Hailing from the German state of Thuringia, the region's Prime Minister Bodo Ramelow expressed his condolences by calling Gauder "intelligent and popular".

Ramelow said: "Today Thuringia has lost one of his most talented athletes and a tireless champion for organ donation, Hartwig Gauder.

"We mourn the loss of a great person, his memory lives on."

Gauder made history in 2003 when he became the first person to climb Japan's Mount Fuji with a second heart.

He also competed in several marathons with his new heart, including in Berlin and New York.

After he ended his career at the World Championships in Stuttgart in 1993, the press voted him "Walker of the Century".