Mar 29, 2009 11:04 AM EST

Astros third baseman Aaron Boone has been taken out of the intensive care unit after open heart surgery performed Thursday at Stanford Medical Center in California.

"It was a little more serious that we kind of expected," Bob Boone, Aaron's father, said. "The surgeon told us it's good we did it now."

Boone said his son had a section of his aorta replaced and had his aortic valve repaired. They knew of the condition since childhood, but it had worsened in recent years.

Via Houston Chronicle