"I'll go ahead and repair it and be done with it," the right-hander said.
If the Astros don't reach the playoffs, Sampson will undergo the surgery on Oct. 1. If the Astros do make the postseason, Sampson will be available to pitch and will have the surgery when the season is complete.
An MRI taken of Sampson's elbow on Wednesday revealed the tear, and later that night, Sampson said he needed more time to decide if he wanted to have the surgery or opt for rest and rehab with hopes that would remedy the problem.
Team doctor Tom Mehlhoff recommended surgery, according to Sampson.
Recovery time is expected to range from four to six months.
Alyson Footer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.