Clinton undergoes successful surgery

Former US President Bill Clinton was out of surgery with no complications yesterday after undergoing a procedure to remove scar tissue and a build-up of fluids in his chest, authorities said.

"Doctors called us about 10 minutes ago to say he was out," said Rob Nyers, a spokesman for the New York Police Department, which was assisting with Clinton's security. The former president was "ok," he added.

Mr Clinton had entered New York-Presbyterian hospital before dawn for the surgery, a low-risk procedure doctors say is rarely necessary as a follow-up to the quadruple heart bypass surgery the former president had last year.

There was no immediate comment from the former president's office or hospital officials, but police told reporters to expect a briefing from doctors shortly.

Mr Clinton is expected to remain hospitalised from three to 10 days to make a full recovery, the doctors said before the surgery.

The procedure, called a decortication, is "relatively low-risk" but rarely done as a follow-up to bypass surgery, doctors said. It requires general anesthesia.

Dr Craig Smith, chief of the hospital's division of cardio-thoracic surgery, said in some 6,000 cases of bypass surgery like Mr Clinton's, he had seen fewer than 10 cases that required the follow-up surgery.

"This is the extremely unusual end result of an extremely common process," Dr Smith said at a news conference on Tuesday.

Mr Clinton has been suffering from a condition called a pleural effusion, in which scar tissue has caused fluid to build up around and compress his left lung. It has caused him shortness of breath while exercising and some chest discomfort, doctors said. The aim of the surgery was to remove the thick scar tissue over his lung and drain the built-up fluid.

Doctors said Mr Clinton, who served eight years in the White House from 1993 until 2001, recently passed a stress test "with flying colours".

He recently travelled across Asia with former President George H. W. Bush to review aid operations following the tsunami disaster in the region.

Doctors said Mr Clinton's activities had not contributed to his need for the surgery. The former president knew before his trip that he would need to undergo the procedure, they said.

At the time of his bypass, doctors said Mr Clinton would have risked a "substantial" heart attack without surgery because some of his arteries were 90 per cent blocked.