The game-winning tally came early in the third stanza when Andrighetto sent the puck at the Canadian net and Gaetan Haas tipped it past netminder Darcy Kuemper (Arizona Coyotes).
Canada made a late push and Colton Parayko (St. Louis Blues) cut the deficit in half with a 6-on-5 marker in the final three minutes of the outing.
Avs forward Tyson Jost was on Canada's second line with Kyle Turris (Nashville Predators) and Ryan O'Reilly (Buffalo Sabres) and had one shot on goal in 8:41 of ice time.
Canada outshot Switzerland 45-17 but Swiss goalie Leonardo Genoni was reliable between the pipes and made 17 saves in each of the second and third periods.
Switzerland was 2-for-3 on the power play while Canada could not capitalize on its only opportunity with the man advantage which came midway through the final frame.
Team Switzerland faced Sweden in the preliminary round at the tournament and fell 5-3 but will be looking for redemption and a gold medal at Royal Arena on Sunday. Meanwhile, Jost and Team Canada will face the United States, who lost 6-0 to Sweden on Saturday, in the bronze-medal game.
