President George H.W. Bush through the years

<div class="meta image-caption"><div class="origin-logo origin-image "><span></span></div><span class="caption-text">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&#39;s thyroid disorder, called Graves&#39; disease, caused the irregularity. It was responsible for a similar episode he suffered while jogging in May 1991.  (AP Photo&#47; DAVID J. PHILLIP)</span></div>
December 28, 2012 9:29:18 AM PST