WASHINGTON — Former President Bill Clinton, whose appetite for fast food and fluctuating waistline cemented his pudgy persona with the public, will undergo heart bypass surgery as early as today in a New York hospital because of heavy blockages of his arteries.

Clinton's prospects are good for a full recovery from a surgery that's performed on more than 300,000 people each year with a 97.6 percent survival rate. The several hours of surgery will involve taking other arteries or veins and rerouting blood away from blocked areas and into the heart.

Clinton, 58, who suffered "mild chest pain and shortness of breath" Thursday afternoon, went to Northern Westchester Hospital and, after tests, was sent home later that night, according to a statement from the former president's office in Harlem. After more tests at Westchester on Friday morning, Clinton was transferred to New York Presbyterian Hospital in Manhattan for upcoming surgery.

"He's in excellent hands and he's at one of the great hospitals in the world," his wife, Sen. Hillary Rodham Clinton, D-N.Y., said Friday at the New York State Fair in Syracuse as she left to be with the former president and their daughter Chelsea at the hospital.

The hospital and the former president's office aren't releasing details of the surgery, which reportedly is being planned as a quadruple bypass.

The former president is relatively young for the surgery, experts said, which means he has a better than average chance of undergoing surgery without complications and resuming a normal life. More than half of the nation's bypass surgeries are performed on people 65 and older.

"Once you get the grafts on you, you're good to go. Essentially you've got a re-load on the shotgun," said Dr. Randolph Chitwood, the chief of cardiothoracic surgery at East Carolina University's School of Medicine, who underwent bypass surgery when he was 47. "I consider I was recharged and ready to go again."

The surgery is much like installing new plumbing, Chitwood said. It involves putting inch-long patches of arteries or veins from elsewhere — legs, arms or elsewhere in the chest — around the blockages. Most of the time, the patient's heart is stopped during the operation, but for patients older than Clinton is, doctors sometimes do the surgery while the heart continues to beat, Chitwood said.

The procedure is relatively rare for men Clinton's age. Only 5 of 1,000 men aged 45 to 64 had bypass surgery in 2001, according to statistics kept by the Centers for Disease Control and Prevention. On average, the surgery cost about $61,000 in 2001. The government pays ex-presidents' medical bills.

Bypass surgery generally isn't done unless 75 percent of an artery is blocked, said Dr. George Sopko, a cardiologist at the National Heart Lung and Blood Institute in Bethesda, Md.