Six months after undergoing heart bypass surgery, President Clinton will return to the hospital this week to have a rare buildup of fluid and scar tissue removed from his chest.

“I feel fine,” Mr. Clinton said yesterday in Washington, adding that he plans to play golf in Florida a day before the operation.

Doctors at New York-Presbyterian Hospital/Columbia University Medical Center, where Mr. Clinton is scheduled to have the procedure tomorrow, said the surgery is low-risk.

During the procedure, known as a decortication, doctors will remove scar tissue that is pressing down on his left lung. The surgery will be done either through a small incision or with a video-assisted thorascope inserted between his ribs.

The former president said doctors discovered the condition during a recent X-ray, and he called the surgery a “routine sort of deal.”

In an interview with Associated Press Television News, Mr. Clinton said he knew before he went with President George H.W. Bush to tour tsunami-devastated areas last month that he would be having the surgery. Doctors told him he would not be able to fly after the surgery, so he scheduled it after he returned.

Mr. Clinton said he will play in a charity golf tournament for tsunami relief today with the elder Mr. Bush.

“I feel fine. I just had a little fluid buildup after my surgery,” Mr. Clinton told APTN. “It’s no big deal.”

Mr. Clinton’s problem is a rare complication of his surgery, where inflammation of the lining of the heart develops and fluid builds around it or in the lungs, said Dr. Craig Smith, who performed the bypass surgery on Mr. Clinton in September. He said it occurs in “a fraction of 1%” of cases.

Dr. Allan Schwartz, chief of the cardiology at New York-Presbyterian, said Mr. Clinton passed a full physical before going to Asia and scored in the 95th percentile for his age in a stress test.

Mr.Clinton, 58, had been quite active since his September 6 heart surgery at Columbia-Presbyterian, presiding over the opening of his presidential library in Little Rock, Ark., and, more recently, joining the first President Bush for a public relations campaign to help raise private funds for the victims of the Asian tsunami.

The elder President Bush said he had trouble keeping up with Mr. Clinton in Asia. “You should have seen him going, town to town, country to country, Energizer Bunny here. He killed me,” Mr. Bush said.

Mr. Clinton underwent quadruple coronary artery bypass surgery after suffering chest pains and shortness of breath.

In bypass surgery, doctors remove one or more blood vessels from elsewhere in the body and attach them to arteries serving the heart, detouring blood around blockages. The vessel typically comes from elsewhere in the chest, although doctors sometimes take one from an arm, a leg, or the stomach.

Mr. Clinton previously blamed his blockage 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.”

Mr. Clinton said he would return to work as soon as possible following the surgery.

“I’m going to slow down for the next couple of weeks,” he said. “But I’m in good shape.”