Democratic presidential candidate Bill Bradley today dismissed his previously undisclosed heart ailment as "just a nuisance" that will not slow his campaign and should not cause voters to be concerned about his health.

A day after he was forced to cancel several Bay Area and Washington state political events because of what his doctors call an "atrial fibrillation," or irregular heartbeat, the former New Jersey senator told a news conference here that he blamed himself for the problem. On Wednesday, Bradley said, he skipped taking the daily medication prescribed for the condition. The problem was first diagnosed in 1996, while he was still in the Senate, and since 1998 he has been taking twice daily doses of Procanbid pills to control the condition.

Bradley said he had planned to make the problem public next Monday, as part of a full medical report, but joked that his heart had decided on its own to move up the date of disclosure.

Before flying to Florida to resume his schedule, Bradley met with reporters in a hotel near the Stanford University campus in an effort to dispel a public reaction that could damage his challenge to Vice President Gore for the Democratic presidential nomination.

It is not unusual for candidates to have to cancel events for health reasons--ranging from laryngitis to flu--but the fact that this previously unknown condition involves his heart was viewed by Bradley aides as one that might cause some voters to worry if he is healthy enough for a campaign, or four years in the White House.

Gore, in Atlanta, said it was "good news" that Bradley was back campaigning. "He's a good man, a great competitor. I look forward to continuing our discussion of the issues." Earlier some Bradley aides complained privately that a Gore spokesman's offer of "good wishes and prayers" for Bradley's health was a lightly disguised effort to make people think it was a serious condition.

Bradley said that his physicians have assured him that his atrial fibrillation was not a symptom of more serious heart problems. He recalled that President George Bush was diagnosed with a similar ailment in 1991 and said that "millions of others" have the same condition.

Bush's problem was attributed to a malfunction of his thyroid gland, but Bradley's New York physician, Robert H. Heissenbuttel, said he has found "no precipitating cause" for Bradley's condition.

Bradley said he experiences no pain when the heart loses its normal sequencing and begins to beat more rapidly and irregularly, as it did during a campaign stop Thursday in Sacramento. He said he consulted by phone with a Berkeley cardiologist, Ed Anderson, he had met in 1998, while he was a visiting professor at Stanford University, and they decided to give the heart 24 hours to restore its normal rhythm before applying an electric defibrillator to correct the problem.

When it persisted, Bradley canceled an environmental event on the San Francisco waterfront and scrapped plans to fly to Seattle for events there. But as he was traveling to a hospital here to meet Anderson for the corrective procedure, the heart spontaneously resumed its normal beat. "It just flipped back in," he said.

Bradley said he had had a similar episode in New York several months ago, which he attributed to a delay in taking the pills, which he is supposed to take four at a time at intervals of 12 hours. In that case, he said, the normal heartbeat restored itself without treatment after about 10 hours.

Heissenbuttel, in a letter released late Thursday, said there had been seven previous episodes since 1996 and "the medication has been effective in preventing or shortening the duration of episodes and has been well tolerated with no side effects."

The candidate said he was "feeling great" after a night's rest and said he had no concern that the demands of the campaign would put too great a stress on his system. He said his schedule for the first two years after he retired from the Senate was more demanding than his current pace.

This is "just one of those things," he said, adding that he feels more aches and pains from his days as a pro basketball player than discomfort from any heart condition.

Bradley said his latest checkup, on Dec. 3, showed "no other health issues other than the arrhythmia" that recurred a few days later.

Bradley said he had timed the exam to be "as close as possible" to the most demanding period of the campaign, so voters could have the most current information on his health. He planned to release the results on Monday, he said.

Asked if he thought the episode would create reservations about his candidacy for some voters, Bradley replied, "Not if they read your reports."