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Former President George Bush, right, answers questions about his heart condition as cardiologist Mark Hausknecht laughs during a news conference at Methodist Hospital on Friday, Feb. 25, 2000 in Houston. Bush spent Thursday night in a Florida hospital and was released Friday after being treated for an irregular heartbeat. Doctors will investigate whether Bush's thyroid disorder, called Graves' disease, caused the irregularity. It was responsible for a similar episode he suffered while jogging in May 1991.
(AP Photo/ DAVID J. PHILLIP)