If you've had a heart attack or recurring angina, chances are you've either had or been recommended to have an angioplasty. Or, as it's now called, percutaneous coronary intervention.

Contrary to popular belief, however, angioplasty does not prevent heart attacks or save lives.

Studies show harm

Conventional wisdom dictates that angioplasty is best done within 12 hours after a heart attack, but at least a third of patients aren't treated within that time frame. Nevertheless, "late" angioplasty is routinely performed on the assumption it provides benefit. Well, it doesn't.

A large, multicenter study published in the New England Journal of Medicine revealed when angioplasty was done three to 28 days after a heart attack, it failed to reduce occurrence of death, repeat heart attacks or heart failure.

Even worse, during four years of follow-up, there were more heart attacks in the group that had angioplasty, compared to those treated conservatively with drugs.