"I talked to him the other day and he's back, 100 percent, skating, working out," Flames general manager Brad Treliving told the Calgary Herald on Thursday. "He's been back in his routine, fully functional, and no issues."
Hiller, who had the attack while training in his native Switzerland, had an arthroscopic procedure in mid-July.
"These things can happen, obviously ...," Treliving told the newspaper. "Your first thought is concern for his well-being, then you do your homework and find out more information. We don’t expect it to be an issue."
Hiller signed a two-year contract with the Flames on July 1 as a free agent.
The 32-year-old was 29-13-7 with a 2.48 goals-against average and .911 save percentage in 50 regular-season games for the Anaheim Ducks last season.