Hickstead died of a ruptured aorta that led to heart failure last Sunday at an international show-jumping tournament in Verona, Italy, according to an autopsy report released Wednesday.
His rider, Eric Lamaze, said he believes that when the horse collapsed after he completed his round that he ensured that his rider would not be hurt when he went down.
Lamaze said that while he still has a number of talented horses to ride, he does not have another of the calibre of Hickstead to take to the London Olympics next year.
Although in the devastating moments after Hickstead's death, Lamaze said he considered retirement, he said he will push on and look for a replacement for Hickstead.
A horse that competes for Canada must be owned by a Canadian citizen by Dec. 31 the year before the Games, according to Olympic rules.
Lamaze competed at the Royal Agricultural Winter Fair on Tuesday night for the first time since Hickstead died. As soon as he entered the ring, the crowd gave Lamaze a standing ovation. Members of the grounds crew wore black armbands in tribute to Hickstead.