Lewis Clear to Resume NBA Career : Basketball: New tests results contradict the earlier diagnosis of a life-threatening heart ailment.

In a stunning turnaround that could have ramifications in Boston medical circles if not the sports world, cardiologists said Monday that Reggie Lewis could resume his career with the Boston Celtics.

A week ago, Lewis’ career was thought to have ended prematurely when it was announced he suffered from a heart disorder known as focal cardiomyopathy.

After seeking a second opinion, however, Lewis’ condition has been diagnosed as vaso depressor syncope, which is not life-threatening. Gilbert Mudge, director of clinical cardiology at Brigham and Women’s Hospital in Boston, said Lewis has a normal athlete’s heart in announcing the findings.

Lewis, 27, was Boston’s leading scorer this season and the player who replaced Larry Bird as Celtic captain.

On the verge of becoming an NBA star after toiling six years in the league, Lewis passed out April 29 in the Celtics’ first playoff game against the Charlotte Hornets. After the episode, Lewis was admitted to New England Baptist Hospital and administered a series of cardiac examinations.

A group of 12 specialists concluded that Lewis suffered from cardiomyopathy, which can cause sudden cardiac arrest with physical activity. Mark Estes, the electrophysiologist who handled some of the exams, told The Times last week: “Really, (there was) unequivocal evidence of the focal defects at the apex of the left ventricle.”

Estes refused to discuss the latest revelations, saying he did not have enough information.

But Monday’s disclosure contradicts the findings from New England Baptist and could divide Boston’s medical community, sources said. New England Baptist physicians were privately upset that Lewis left their care after 48 hours to transfer to Brigham and Women’s last Sunday.

Mudge said he first questioned the original diagnosis when noticing inconsistencies in some data. He said he decided to redo some tests and add other ones.

Mudge said he realized his findings were controversial.

“That’s why I had to be absolutely sure,” he said. “I’m well aware they had a panel of 12 experts. . . . Other people can disagree all they want. But this is how we’re approaching it.”

Lewis, who appeared with his wife, Donna, and the doctors at a news conference, looked relaxed and relieved.

“I’m just glad it’s finally come to an end,” said Lewis, in the final year of a five-year, $16.5-million contract.

Lewis was discharged from the hospital and said he plans to play next season. Mudge said he expects Lewis to resume regular training by mid-summer.

Dave Gavitt, Celtic vice president, told reporters: “This is the best news I’ve had in a long time.”

Lewis’ condition can be treated with a variety of antiarrhythmia medications that help prevent an irregular heartbeat. Some of the common medications include beta blockers or Norpace. Some are more tolerable than others, but most cause some type of side effect.

The symptoms of Lewis’ syndrome are similar to an arrhythmia, or fast heartbeat, although the causes are vastly different. The syndrome is caused by the nervous system’s paradoxical reaction to upright tilting.

Mudge used a relatively new procedure called a tilt test to help determine the problem. A tilt test can cause the heart to beat erratically with the aid of other instruments.

The test is relatively simple: While lying flat on his back on a movable examining table, the patient’s blood pressure, pulse and heart rhythm are monitored for about 10 minutes.

Then the table is suddenly tilted with the patient’s head up. The heart is monitored by an electrocardiogram. The movement often produces an irregular heartbeat and reproduces the symptoms of fainting. But when it fails to show any change in pulse rate or blood pressure, additional medications can be used to further test the heartbeat.

Mudge said technicians were able to reproduce Lewis’ symptoms, and Lewis passed out after six minutes of tilting, indications the test was conclusive.

Mudge said Lewis had complained of being lightheaded for the past four months. But his problem became pronounced when he collapsed while playing. At first, Celtic officials thought he bumped his head and allowed him to return to action. But when he complained of dizziness, he was sidelined, then sent to the hospital.

Lewis’ condition is believed to be among the most common causes of fainting episodes, according to David G. Benditt from the University of Minnesota Medical School.