MacArthur, however, remains under contract through 2019-20, meaning it's possible, albeit unlikely, that he could play in the future if medically cleared.
"Oh, I doubt that one," Dorion said on TSN Radio 1200 in regards to whether MacArthur will play this season. "He's moved to Florida, if I'm not mistaken. And after failing that medical... You know what, if he wants to come back next year and try, we'd definitely look at it."
Following a series of serious concussions, MacArthur was able to play late last season, recording three goals and six assists in 19 playoff games.
"Clarke was a big part of our playoff success, but I think health (and) family comes before hockey any day," Dorion added. "I couldn't be responsible for allowing him to play after doctors said that he failed his medical."
MacArthur, who carries a $4.65-million cap hit, is currently listed on long-term injured reserve.