The moves were made on Friday, shortly before Buffalo hosted the Montreal Canadiens.
Catenacci is being evaluated for a concussion after he had his head down and was checked by Flyers defenseman Radko Gudas in Buffalo's 5-1 loss at Philadelphia on Thursday.
The Sabres are already down three forwards after Zemgus Girgensons (lower body) was placed on injured reserve on Wednesday.
Varone leads AHL Rochester with 12 goals in 38 games this season and is being called up for the first time this year. He had five goals and three assists in 41 games with the Sabres over the previous two seasons.