New Orleans ? People terrified by crippling chest pains want their doctors to do something fast to make them feel better and cut the chances they’ll have a heart attack or die.

For years, doctors have done artery-opening angioplasties for these reasons.

Now, stunning results of a landmark study have proved them wrong.

Researchers found that angioplasty did not save lives or prevent heart attacks in nonemergency heart patients.

An even bigger surprise: Angioplasty gave only slight and temporary relief from chest pain, the main reason it is done.

“By five years, there was really no significant difference” in symptoms, said Dr. William Boden of Buffalo General Hospital in New York. “Few would have expected such results.”

He led the study and gave results Monday at a meeting of the American College of Cardiology. They also were published online by the New England Journal of Medicine and will be in the April 12 issue.

Angioplasty remains the top treatment for people having a heart attack or hospitalized with worsening symptoms. But most angioplasties are done on a nonemergency basis, to relieve chest pain caused by clogged arteries crimping the heart’s blood supply.

Those patients now should try drugs first, experts say. If that does not help, they can consider angioplasty or bypass surgery, which unlike angioplasty, does save lives, prevent heart attacks and give lasting chest pain relief.

In the study, only one-third of the people treated with drugs ultimately needed angioplasty or a bypass.

About 1.2 million angioplasties are done in the U.S. each year.