ULTRAFAST CT NONINVASIVELY PROVIDES CLUES TO EARLY HEART DISEASE

Emory doctors are increasingly adding a new imaging technology to their set of cardiac diagnostic tools. Electron beam computed tomography (EBCT), also known as ultrafast CT, can detect evidence of early coronary artery disease years before symptoms appear.

The system scans for calcium in the coronary arteries ­ a marker for vessel-clogging atherosclerosis. The test is noninvasive and uses no contrast dyes. Compared with conventional techniques such as electrocardiogram (ECG) or exercise thallium stress test, EBCT requires no physical exertion. Since a vessel must already be narrowed by 50 percent or more to be picked up by a stress test, EBCT has the potential to detect possible coronary artery disease at an earlier stage.

Emory cardiologists and internists say EBCT is especially useful in young-to-middle aged adults who are at risk for heart disease yet have no symptoms, who nonetheless wish to check for early signs of plaque formation. Some doctors say the test may be useful in persons with advanced cardiac disease who are having trouble making lifestyle changes such as quitting smoking and losing weight associated with reducing risk for heart disease. Actually "seeing" signs of atherosclerosis in one's own coronary arteries can, according to some doctors, serve as an important impetus to change.

"If we know who has the disease, we can offer very effective treatment," says Randolph E. Patterson, M.D., director of Cardiovascular Imaging for Emory Heart Center, who has served as the initial medical director at LifeTest Cardiac Imaging, the state's only EBCT center. "The problem has been that we often don't know who has coronary atherosclerosis until the person has a heart attack, sudden death or develops symptoms. At these points, treatment options decrease or end.

"The electron beam tomography system provides an accurate test for coronary artery disease per se -- not just its consequences -- before symptoms appear," he says.

"If a person has coronary atherosclerosis, the American Heart Association recommends more intensive efforts to lower cholesterol levels and decrease other risk factors. For example, a physician would be more likely to recommend drug treatment to lower cholesterol if the patient were known to have heart disease. Also, patients who know they have the disease are more highly motivated to change their lifestyle through improving diet, exercising and quitting smoking."