The article to be published in Vanity Fair, and already posted on the magazine's website also questions some of Clinton's business dealings and behaviour since leaving the White House.

"Old friends and long time aides are wringing their hands over Bill Clinton's post White House escapades, from the dubious (and secretive) business associations to the media blow-ups that have bruised his wife's campaign, to the private-jetting around with a skirt-chasing, scandal-tinged posse," the article said.

Some, it said, point to Clinton's medical traumas; others blame sheer selfishness, and the absence of anyone who can say "no," it added.

It also asserts that several of his aides were concerned about reports of his inappropriate behaviour during his travels and one of them unsuccessfully attempted to intervene, believing he was "apparently seeing a lot of women on the road."

The Clinton campaign immediately hit back, saying the theory was flatly rejected as "false" by his doctors who say he is in excellent health and point to his vigorous schedule as evidence of his exceptional recovery.

Bill Clinton also lashed out at journalist Todd Purdum, who wrote the article, for bringing negative attention to his wife's candidature campaign, calling him a "sleazy", "slimy" and "dishonest" reporter, Huffington Post said.

Purdum, a former White House reporter for the New York Times and the husband of former White House Press Secretary admitted he had no evidence but was reporting what the former and current aides of Clinton are saying.

Besides, the theory that the heart surgery had altered his behaviour was based on a doctor who had not seen Clinton.

The editor, who infuriated the Clinton campaign with the explosive article strongly defended his reporting in an interview to CNN. He stood by his article's most controversial assertions including charges that aides to the former president believe his 2004 heart surgery altered his state of mind and that some of them grew concerned with rumors Bill Clinton had been "seeing a lot of women on the road."

But he repeatedly said he was not insinuating that Clinton had been involved in inappropriate behaviour but rather reporting what aides had become concerned with.

"I'm very careful to say that there is no clear-cut evidence that President Clinton has done anything improper," he said.

"What I am careful to say, is that this former senior aide was concerned enough that prominent Democrats around the country were complaining about hearing reports of this that he felt President Clinton... should know that it was out there in the slipstream ... and that it could have an effect in the campaign season."

The Web posting prompted a blistering response from Clinton campaign spokesman Jay Carson Sunday night, who called the piece "journalism of personal destruction at its worst."