Triple Olympic champion Janica Kostelic pulled out of Wednesday's women's downhill because of an irregular heart-beat.
Kostelic won golds in slalom, giant slalom and combined in 2002
The 23-year-old Croatian had been planning to compete in all five Olympic alpine disciplines in Turin.
Kostelic missed the 2003-04 season after thyroid gland surgery, and had a sixth knee operation last summer.
"She had a higher pulse and after her thyroid operation we want to be careful," said a team spokesman.
"She will start in all the other disciplines but not in today's downhill."
Kostelic, who was tipped as one of the strongest contenders in the downhill, won the slalom, giant slalom and combined in Salt Lake City in 2002.
The only other skiers to win three golds at a single Games are Toni Sailer in 1956 and Jean-Claude Killy in 1968.