Houston ? Former first lady Barbara Bush was resting comfortably after undergoing successful open heart surgery Wednesday to replace her aortic valve, a family spokesman and hospital officials said.

The surgery at The Methodist Hospital lasted about 2 1/2 hours and was scheduled last week after Bush, 83, experienced a shortness of breath, family spokesman Jim McGrath said.

He said doctors determined the aortic valve had started to harden.

Dr. Gerald Lawrie, a heart surgeon at the Methodist DeBakey Heart & Vascular Center, replaced the valve with a biologic valve, which is made of natural living tissue, the hospital said in a statement. Lawrie said the surgery went “extremely well.”

“I expect her to recover fully and soon resume her normal activities,” Lawrie said.