Astros third baseman Aaron Boone had open-heart surgery in California yesterday to replace a bicuspid aortic valve.

Boone, 36, was diagnosed with a congenital defect in his heart where the valve has two - not the normal three - cusps to manage blood flow. The surgery was performed at Stanford University Medical Center.

"Aaron Boone is doing fine and awake following surgery. We were able to preserve the leaking aortic valve and replace the ascending aortic aneurysm [a swelling of the aorta]," Dr. D. Craig Miller, who performed the surgery, said in a statement.

Boone is a member of one of baseball's most famous families. His father is former Phillies catcher Bob Boone. Brother Bret and grandfather Ray were also longtime big-leaguers.

"I spoke to Aaron's father, Bob, and he indicated that things went well," Houston general manager Ed Wade said. "Certainly our prayers are with Aaron and the entire Boone family in hopes of a full recovery."

The Astros signed Boone in the offseason. He announced his condition at spring training on March 18 and said he's uncertain if he'll ever play baseball again. He said his recovery from the surgery itself would take "several months."

Boone has played for Cincinnati, the New York Yankees, Cleveland, Florida and Washington in his 12-year career. He is best known for his 11th-inning homer off Boston's Tim Wakefield in Game 7 of the 2003 AL Championship Series that sent the Yankees into the World Series.

Boone said at spring training that he felt fine, but a routine physical determined he needed surgery. *