NEW YORK - Bill Clinton had a successful quadruple heart bypass operation Monday to relieve severely clogged arteries that doctors said had put the former president in grave danger of a major heart attack sometime soon.
Clinton is expected to make a full recovery, but doctors said he was fortunate to have checked himself into the hospital when he did. The heart disease they repaired was extensive, and blockage in several of Clinton's arteries was "well over 90 percent," said Dr. Craig R. Smith, the surgeon who led the operation.
"There was a substantial likelihood that he would have had a substantial heart attack," said Dr. Allan Schwartz, chief of cardiology at New York Presbyterian Hospital/Columbia.
Smith said Clinton could leave the hospital in four or five days. Clinton was awake but sedated about four hours after the operation ended, Schwartz said.
The four-hour surgery came three days after Clinton arrived at the hospital complaining of chest pain and shortness of breath. But doctors said Clinton's problems were not as sudden as had been portrayed. He had suffered shortness of breath and tightness in his chest for several months, blaming them on off-and-on exercising and acid reflux, his doctors said.
In addition, the former president had high blood pressure and may not have been adequately treated for high cholesterol. His doctors said Monday he was put on a cholesterol-lowering drug a few days ago. Clinton was prescribed cholesterol medicine in 2001 as he was leaving office.
In a statement, Clinton's wife, Sen. Hillary Rodham Clinton, thanked the hospital staff for helping the family through a trying time.
"Bill, Chelsea and I stayed up pretty late last night talking, playing games and just being with each other," the senator said. "These past few days have been quite an emotional roller-coaster for us."
She added: "The president's optimism and faith will carry him through the difficult weeks and months ahead _ of that we have no doubt."
In bypass surgery, doctors remove one or more blood vessels from elsewhere in the body _ in Clinton's case, two arteries from the chest and a vein from the leg _ and attach them to arteries serving the heart, detouring blood around blockages.
During the operation, Clinton's heart was stopped and he was put on a heart-lung machine for 73 minutes. That process, used for more than 75 percent of bypass patients, carries a small risk of stroke and neurological complications.
As many as 30 percent of patients suffer "measurable but very subtle" problems in mental functioning after bypass, but those problems are gone within a year, Smith said.
Asked whether there were any troubling moments during the surgery, Smith said: "There are always a few minor anxious moments during heart surgery. There was nothing in this case that was outside the realm of routine."
Schwartz said it would be possible for Clinton in the future to lead an "extraordinarily active lifestyle" _ including hitting the campaign trail.
"He is recovering normally at this point. Right now everything looks straightforward," Smith said.
Still, Dr. W. Randolph Chitwood, chief cardiovascular surgeon at East Carolina University and a spokesman for the American College of Cardiology, agreed with Clinton's doctors that the president had been in a dangerous state leading up to the operation. "Within the next couple of weeks, something was going to happen," he said.
Doctors delayed surgery until Monday because Clinton was on the blood-thinning medication Plavix, and waiting a few days decreased the chance of excessive bleeding, they said.
Clinton was described as upbeat in the days before the surgery, resting with his wife and daughter. One New York Post photo showed the former president reaching for a Boggle game near his hospital-room window.
Clinton has blamed his heart problems in part on genetics _ there is a history of heart disease in his mother's family _ but also said he "may have done some damage in those years when I was too careless about what I ate."
He was lampooned during his presidency for his inability to resist fatty fast food, but he was also an avid jogger during his two terms in the White House.
In recent months he has appeared much slimmer. He has said he cut out junk food, begun working out and adopted the low-carbohydrate, lowfat South Beach diet.
Clinton had planned to campaign for Sen. John Kerry, the Democratic nominee for president, but the recovery from surgery will take him off the stump _ at least for now _ with just two months left until the election.
From his hospital room before the surgery, Clinton had a long telephone conversation with Kerry on campaign strategy, said a Democratic official familiar with the talk who spoke on condition of anonymity. Some polls have shown Kerry trailing President Bush since last week's Republican convention.
Both candidates wished Clinton the best after the surgery. "I know you will join with me in wishing President Clinton the very best wishes in the recovery from his surgery," President Bush said at a campaign rally in Poplar Bluff, Mo. "We just pray for a speedy recovery."
Meanwhile, more than 45,000 get-well wishes poured in for Clinton, including tens of thousands of e-mails sent to the Web site of his presidential library.
"You are surrounded by cherished family, friends and a nation that adores you and prays for your full and complete recovery," wrote Toni Maryanna Rossi. "You'll be jogging 5 miles a day in no time."
Associated Press writers Deb Riechmann in Poplar Bluff, Mo., and Marilynn Marchione in Milwaukee contributed to this story.