Common Heart Procedure Shown Ineffective for Some Patients

Nov. 14, 2006 — -- The way in which doctors treat heart-attack patients may soon change because of the results of a new study.

The findings of the study, released today at the American Heart Association meeting in Chicago, show that percutaneous coronary intervention (PCI), a practice in which doctors mechanically open a clogged artery, does not reduce the chances of death or a second heart attack over the next four years if performed three days to 28 days after a heart attack.

The randomized study involved 2,166 heart patients, and is published in this week's issue of the New England Journal of Medicine.

A heart attack occurs when there is a blockage of one or more of the coronary arteries -- the smaller vessels that wrap around the heart and supply the heart muscle with blood. This blockage often comes in the form of plaque buildup on the artery walls or a clot that has become lodged in the vessel.

A blockage means no blood, and no blood means that the part of the heart muscle that is supplied by the vessel will die. Traditionally, doctors believed that re-opening the blocked vessel with an angioplasty and propping it open with a tiny wire tube called a stent, even days after an attack, increased the patient's chances of ending up with a healthier heart.

The findings of the study, however, suggest otherwise -- and they could bring about a major change in protocol for doctors who treat heart-attack patients.

Experts say the change could affect tens of thousands of patients, although firm numbers are difficult to nail down.

"We had expected that angioplasty to open arteries would reduce the risk of subsequent clinical events, specifically heart failure and death in this population that was stable after the initial heart attack but at increased risk of events in the future," said Judith Hochman, the study's lead author and the director of cardiovascular clinical research at the New York University School of Medicine. "We thought it was possible that the risk of a recurrent heart attack would also be reduced. … The results were surprising and do warrant a major change in practice."

The change suggested by the findings involves reserving an angioplasty for patients who are still in the acute phase of their heart attacks, within hours of onset.

Patients who had experienced a heart attack after more than 12 hours would not be given the treatment; doctors instead would rely on medication.

"Some ardent advocates of the 'open-artery hypothesis' have proposed that it is always better to open any closed vessel after a heart attack," said Dr. Steven Nissen, chairman of the department of cardiovascular medicine at the Cleveland Clinic Foundation in Cleveland. "Although virtually every study shows that opening the closed artery within 12 hours is beneficial, we have never examined the value of later intervention."