Vokoun had been hospitalized since Saturday when he had a procedure performed to dissolve a blood clot in his pelvis.
There is no timetable for him to return to the team.
Vokoun went 13-4-0 with a 2.45 goals-against average in 20 regular season games for the Penguins last season, and went 6-5 with a 2.01 GAA in 11 Stanley Cup Playoff games. He replaced Marc-Andre Fleury as starter for Game 5 of the team's first-round series against the New York Islanders, and backstopped the Penguins to the Eastern Conference Final.
I'm here to develop a winning culture and a winning team. There is a bright future ahead of this team. A lot of young, great hockey players here and on the way … a fan base that's passionate about the game of hockey.
— Dan Bylsma after being introduced as new coach of the Buffalo Sabres