NEW YORK ? Former president Bill Clinton left hospital Friday saying surgery to open a blocked artery had been "miraculous" and that he would return to his fundraising work for Haiti.

"It's miraculous with the stents," Clinton told reporters, referring to the devices used to clear a clogged artery during the operation Thursday.

Clinton, 63, was speaking publicly for the first time since entering the New York Presbyterian Hospital. He was released earlier Friday.

"I didn't [take] any sedatives or anything, so I was alert. I wanted to watch it. I got to watch it on the monitor," he said.

Clinton, who underwent quadruple bypass surgery to free four blocked arteries in 2004, had been complaining of chest discomfort, leading doctors to decide on the operation.

"I didn't really notice it until about four days ago, then I felt just a bit of tingling, not pain, no grabbing in my chest. I thought I ought to check it out," Clinton said.

Clinton also issued a written statement saying he would resume his work as a special UN envoy to Haiti and his role, together with former US president George W. Bush, in coordinating relief for Haitian earthquake victims.

"In my capacity as UN Special Envoy for Haiti, I will continue to work with the Haitian government and people, international donors and multilateral organizations," Clinton said.

Exactly a month after the earthquake that killed more than 200,000 people and left some 1.2 million homeless, Clinton said there had been "a generous outpouring of support from donors all over the world."

Clinton was spending the weekend at home in Chappaqua, New York state. He was expected to be back at work Monday and could "resume his very active lifestyle," his cardiologist Allan Schwartz said, underlining that Clinton had not suffered a heart attack. "His prognosis is excellent."

Clinton's wife, Secretary of State Hillary Clinton, and their daughter Chelsea rushed to his bedside Thursday and Hillary Clinton delayed by one day a trip to the Gulf.

Wishes for a speedy recovery poured in from President Barack Obama and others in the political world.

Meanwhile, the tabloid New York Daily News splashed news of the hospitalization with the front page headline "Ill Bill."

Since leaving office in January 2001 after two terms, Clinton has dropped weight, but maintained a punishing routine and was most recently coordinating aid to victims of Haiti's earthquake.

Former Democratic National Committee chairman Terry McAuliffe, who co-chaired Clinton's 1996 re-election campaign, said the ex-president took part in a conference call on earthquake relief to Haiti just as he was being wheeled into the operating room.

"He would have kept the phone on Haiti and talked through the procedure if he could," McAuliffe told CBS television. "He's going to try and get as much in as he can."

Just last week, Clinton paid his second visit to Haiti in a bid to get aid moving to the impoverished Caribbean nation struck by a 7.0-magnitude quake on January 12, and apologized for the slow arrival of relief supplies.

Helen Clark, head of the United Nations Development Programme, told Australian public broadcaster SBS that Clinton's heart problems "won't stop the commitment."

"He'll be working the phones, he'll be sitting in whatever bed he's in and really carrying on the work. Let's hope he has a full recovery."

The medical procedure on Clinton, which is widely used, involves inserting tiny wire-like tubes known as stents into the artery to prevent plaque from building up and blocking the blood flow.

While in the White House, Clinton famously indulged his appetites, including junk food, but in his post-presidential days he adhered to a stricter diet and a busy work schedule.

In a 2005 interview just months after the bypass surgery, he told CNN that prior to going under the knife, he realized that he was "very close to having a serious heart attack."

Clinton was sworn in on Jan. 20, 1993, as the 42nd US president and the first Democrat to hold the highest office in 12 years. He won a second term in 1996.