Yukon Quest dog’s heart stopped

Final results of a necropsy performed on a dog that died during last month’s Yukon Quest Sled Dog Race are in.

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Yukon Quest head veterinarian Nina Hansen said veteran musher Yuka Honda’s dog Firefly had an enlarged heart.

“And likely died of a sudden arrhythmia,” Hansen said. “So the electricity going to the heart would have gone wrong.”

Hansen says many sled dogs have enlarged hearts and live normal lives, while a few die suddenly. She says it appears Firefly did not have “athletic heart syndrome”, an enlarging of the heart common in endurance athletes.

“After looking at the tissues under a microscope, this was not athletic heart syndrome, Hansen said. “So this dog did have acute heart failure.”

Firefly died February 9th a few miles outside Dawson City, the Quest halfway point, and Hansen says it remains unknown what caused the 6 year old dog’s heart to stop.

”In people, heart failure is seen in overweight individuals, individuals with poor diets,” Hansen said. “So some of those same things can cause enlarged hearts in dogs. Obviously that’s not the case with this dog. It was a very fit, well-trained dog. So we don’t know in this case what caused that heart failure.”

Hansen noted that dog booties discovered in the animal’s stomach were not a factor. Firefly was the only dog fatality in this year’s Yukon Quest. Five dogs have died in this year’s Iditarod. Two of those deaths were animals dropped from the race: one from overheating, and the other from being hit by a vehicle. Causes of the on trail deaths are pending necropsies