Hours after deciding to undergo heart bypass surgery, former US president Bill Clinton said he considered himself "very lucky."

"My blockage is so substantial. I think if I don't do this there's virtually a 100 percent chance I'll have a heart attack," he told CNN's "Larry King Live" Friday evening.

Clinton will go under the knife at Columbia Presbyterian Medical Center early next week. But he seemed in good spirits as he discussed his future.

"I feel really blessed, you know, a lot of people who have a heart attack never get an advance warning."

Clinton was taken to Westchester Medical Center Thursday evening for tests after complaining of chest pain and shortness of breath.

An angiogram revealed Clinton has significant blockages in several arteries - serious enough that angioplasty, a procedure where a balloon is used to open up arteries, was ruled out.

Some media reports said Clinton would undergo multiple bypass surgery and others said it would be a quadruple bypass.

"You know, some of this is genetic, and I may have done some damage in those years when I was too careless about what I ate," he said. "For whatever reason, I've got a problem and I've got a chance to deal with it."

After the diagnosis, Clinton checked into Columbia Presbyterian. He was supposed to have met his wife, Sen. Hillary Clinton, at the State Fair near Syracuse. Instead, his wife made an early exit to rush to his side.

"You have heard by now, because it just hit the news, he was admitted into Columbia Presbyterian Hospital in the last hour or so," she announced to the upstate crowd.

Seeming at moments to struggle slightly to maintain her composure, she tried to smile and to downplay the gravity of her husband's condition.

"So I'm leaving here, and I know you understand," she said. "And I'm sorry I'm not going to get a chance to see each of you personally."

Meanwhile, the ex-President called family and friends, including his father-in-law, Dick Kelley, in Hot Springs, Arkansas.

Experts said bypass surgery is serious but very common and the otherwise healthy 58-year-old ex-President should make a complete recovery.

But word of Clinton's heart troubles stunned Democratic leaders and sent shock waves through the campaign of John Kerry, who had been counting on the popular pol to stump for him. "I want you all to let out a cheer and clap that President Clinton can hear all the way to New York," Kerry said at a rally in Newark, Ohio.

Fresh from his big speech at Madison Square Garden, President Bush paused while campaigning in Wisconsin to send Clinton "our best wishes for a swift and speedy recovery." Later, he called Clinton from Air Force One to wish him well, the White House said.

Famous for his Big Mac addiction, Clinton had recently lost a lot of weight, which he attributed to the low-carb South Beach Diet and a strict jogging and workout regimen.

But in recent weeks, friends noticed that the usually hale and hearty Clinton seemed run-down. Yet on Sunday, he managed to give a rousing pro-Kerry speech at Riverside Church in upper Manhattan.

The Clintons had been scheduled to begin a two-day upstate tour,but early Thursday he went instead to Westerchester Medical Center for a more sensitive heart test, an angiogram.

The angiogram revealed the blockage but no heart attack, said Dr. Anthony Pucillo who performed it.

Source: Xinhua