Janka misses two World Championship events
Swiss Olympic giant slalom champion and World Cup titleholder Carlo Janka, who has struggled all season for fitness, will miss the downhill and super combined at the world championships.
However, he will return to take part in the giant slalom next week, the Swiss team said in a statement on Thursday.
Swiss officials said the 24-year-old was still suffering from the after-effects of a virus earlier this year, which caused changes in the rate of his heartbeat and reductions in his athletic capabilities.
In a statement, the team said Janka's condition had been diagnosed in December but withheld from public knowledge.
"After assessing the situation with a number of heart specialists it was decided with Carlo to postpone further treatment until the end of the season as there was no risk to his health," the statement said.
"The deliberate retention of this information from the public was necessary to avoid bringing unnecessary stress and disruption to the race preparations.
"Because of his current condition, the leaders of the delegation have decided with Carlo that he will miss out on the downhill and super combined. Carlos will focus on the giant slalom."
The decision was announced after Janka finished nearly four seconds adrift of the leaders in downhill training on Thursday.
His absence is another blow for the world championships after Ivica Kostelic, the world's top skier on current form, also pulled out of the downhill and super combined.