Former US vice president Dick Cheney, who has a long history of heart problems, was hospitalized Monday after experiencing chest pains, his office said.
The controversial Republican figure was "resting comfortably" at George Washington University Hospital in the US capital and his doctors were evaluating the situation, his office said in a statement.
Hospital doctors told NBC News that the former vice president was stable and may receive additional treatment on Tuesday.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
The television network said Cheney, 69, apparently received an angiogram test so that doctors could look into his coronary arteries, and that the results showed he may need more treatment.
"We don't know what the plan is," one physician told NBC News.
Cheney, who has had four heart attacks since 1978 and had a pacemaker installed in his chest in 2001, was scheduled to meet with former president George W. Bush and other staffers from the Bush administration in Washington on Friday for the first time since they left office in January 2009.
During his third heart attack, Cheney underwent quadruple bypass surgery. His fourth and most recent came in 2000, when he and Bush were elected to the White House.
The battery for Cheney's pacemaker was replaced in 2007 and the entire device was later replaced.
He has undergone two artery-clearing angioplasties and been treated twice with electrical shocks for atrial fibrillation, an abnormal heart rhythm that places him at risk of a stroke if not treated.
In 2005, he underwent surgery for an arterial aneurysm on the back of each of his knees.
