NEW CORONARY PROBE PROCEDURE IGNITES CONTROVERSY.

Byline: Angela La Voie Knight-Ridder Tribune News Wire

Each year, more than 1 million people in the United States undergo coronary angiography, a procedure in which a tiny probe is threaded into the arteries leading to the heart in an effort to locate blocked blood vessels.

But the introduction of a procedure known as electron beam computed tomography (EBCT) has ignited controversy over which procedure should be used in which patients.

EBCT allows doctors to visualize heart blockages without ever piercing the patient's skin, thus avoiding the trauma often associated with angiography. In just a few minutes, EBCT gives an X-ray image of calcium deposits that often clog heart arteries.

Now, a statement issued by the American Heart Association seeks to define who can benefit most from the newer procedure.

Published in the Sept. 1 issue of the journal Circulation, the statement says that EBCT may be most beneficial in helping to detect artery blockages in patients who suffer the crushing chest pain known as angina. The amount of calcium detected in their arteries is related directly to the likelihood of vessel obstruction and potential for heart attack, according to the statement.

For people with chest pain and other heart-disease risk factors, EBCT could help target individuals for ``aggressive risk management, further diagnostic work-up ... and exclusion from high-risk occupations,'' the recommendations state.

Other patients, however, may not have substantial blockage but may have a type of plaque that is unstable, the guidelines say. This type of plaque can rupture, resulting in the formation of a blood clot that may obstruct an artery. In these patients, EBCT may not be as useful, according to the guidelines.

The American Heart Association does not recommend that EBCT be adopted as a large-scale screening tool for heart disease in people who do not have symptoms of, or risk factors for, heart disease.

Dr. Andrew Buda, chief of cardiology at Tulane University in New Orleans, said that EBCT is more useful as a research tool than a clinical tool.

``It's a promising technology with limited application,'' he said. ``There is still no immediate clinical benefit, even in detecting early coronary disease.''

But one member of the 10-person committee that prepared the new guidelines predicted widespread clinical use of EBCT in just a couple of years for people at risk of heart disease.

``I think it will be used as an early-warning system for certain groups. It's simple to do, noninvasive, takes only a few minutes, and is comparable to the cost of other tests,'' said statement co-author Dr. Bruce Brundage, chief of cardiology at Harbor-UCLA Medical Center in Torrance.