Cheney was experiencing pain in his chest and shoulder and admitted himself to Washington D.C.'s George Washington Hospital shortly after 6 a.m. EST.
Preliminary blood tests suggested Cheney did not have a heart attack. But doctors found that his circulation was slowed through a narrowed artery in his heart, causing pain. They used a stent, or a metal scaffold, to reopen the artery at about 10:30 this morning.
"His prognosis is excellent at this point in time," says Alan Wasserman, MD, a professor of cardiology at the hospital. Wasserman added that Cheney should be able to return to a regular schedule within a few weeks.
Cheney has had trouble with blocked blood vessels before. He had his first of three heart attacks in 1978, when he was only 37 years old. That's not unheard of, but it does suggest that Cheney has an aggressive form of heart disease, says Stephen Manoukian, MD, a cardiologist from Emory University in Atlanta who gave commentary for WebMD but did not treat Cheney.
The Republican VP hopeful had a second heart attack in 1984. In 1988, after his third heart attack, surgeons performed bypass surgery to restore blood flow. The bypass was quadruple, meaning he had four blockages at the time.
Wasserman said during a hospital press conference that this newest problem in Cheney's heart appears to have developed sometime since a checkup he had in 1996.
When Texas Gov. George W. Bush selected Cheney as his running mate, he knew the former Wyoming congressman and White House chief of staff had a history of heart problems. Late Wednesday morning, Bush told reporters he had talked with Cheney by telephone, saying he "sounded really strong."
Cheney, 59, says he now leads an "extraordinarily vigorous lifestyle." He says he quit smoking, exercises regularly, and takes medicine to lower his cholesterol levels.
Since his bypass surgery, Cheney has apparently been problem free -- and that included a period in which he served as secretary of defense during the Persian Gulf War. Earlier in the presidential campaign, Jonathan S. Reiner, MD, another George Washington University cardiologist, said Cheney's stress tests "have been stable and unchanged for the past several years."