The former First Lady, 83, had experienced shortness of breath last week. Doctors discovered that she had a hardened valve in her heart and scheduled the surgery. The surgery is described as routine. It lasts about two-and-a-half hours.
Mrs. Bush was up and talking after the surgery.
She should be able to leave the hospital in 10 days. Her husband, George Bush, Sr. is with her at the hospital.
Last November Mrs. Bush had surgery on a perforated ulcer. She was released from the hospital on December 2 from that ordeal.
Doctors say that an untreated hardened aortic valve can lead to heart failure or sudden cardiac death. Symptoms of aortic valve disease are shortness of breath, chest pain or dizziness.
The hospital said she was “awake and alert as she recovers” in the intensive care unit. Her surgeon, Gerald Lawrie, added: “I expect her to recover fully and soon resume her normal activities.”