Blues general manager Doug Armstrong said Wednesday that discussions between the team and Pietrangelo's agent have reached an impasse "for now."
The 23-year-old Pietrangelo, the No. 4 pick in the 2008 draft, has been part of St. Louis' top defensive pairing the last three seasons. He is also the Blues' top scoring threat on the back line.
Pietrangelo had five goals and 19 assists in the lockout-shortened 2012-13 season. He had 12 goals, 51 points and a plus-16 rating in the 2011-12 campaign.
A total of 53 players are expected to participate in camp with practices beginning Thursday.