Zach Franko also scored two for Kootenay (1-0), while Luke Philp had a goal and an assist. Jaedon Descheneau and Rinat Valiev had two assists apiece.
Brady Brassart and Greg Chase scored for Calgary (0-1), which was outshot 35-29.
Ice goaltender Mackenzie Skapski stopped 27 saves for the win. Chris Driedger stopped 30 shots, including a penalty shot midway through the second period off Deschenau, in the Hitmen's loss.
Chase put Calgary on the board first with a goal at 4:06 of the first period, but the Ice replied with five straight, including power-play goals from Reinhart, Philp, and Franko.
Brassart added a short-handed goal for Calgary at 19:00 of the third.
Kootenay was 3 for 7 on the power play while the Hitmen failed to score on their only chance with the man advantage.
Calgary hosts Game 2 on Saturday.