Viewing neck arteries may be more effective than listening to them RELATED VIDEO CNN's Elizabeth Cohen takes a look at the new technique Windows Media 28K 56K

January 6, 1999
Web posted at: 9:38 p.m. EST (0238 GMT)

BOSTON (CNN) -- Thickening in the walls of neck arteries in older people is a strong indicator of an increased risk for heart attack and stroke, according to a new study.

The discovery could lead to the use of ultrasound images of carotid arteries as a screening device, especially for people who have no history of heart disease or stroke-related disease, researchers say.

"By identifying high-risk patients, ultrasound would allow doctors to provide aggressive treatment early," said Dr. Claude Lenfant, director of the National Heart, Lung and Blood Institute, which funded the study.

The results are reported in the latest issue of the New England Journal of Medicine.

Using ultrasound, researchers measured the carotid arteries (which lead from the heart to the brain) of nearly 4,500 Medicare recipients with an average age of 72. All were 65 or older, and all had no previous history of heart- or stroke-related illness. The study participants were tracked for six years.

The 20 percent of patients with the thickest artery walls had more than three times the risk of suffering a heart attack or stroke for the 20 percent with the thinnest walls, even after considering other risk factors such as high cholesterol, diabetes and smoking.

The results indicate that thickening in the carotid arteries is a better indicator of an increased risk for heart attack and stroke than either high cholesterol or high blood pressure.

An ultrasound test of the neck costs about $250 and is non-invasive.

"It's done basically the same way that an ultrasound in a pregnant woman is done to visualize the fetus, except that it's done in the arteries of the neck," said Dr. Teri Manolio, a cardiovascular epidemiologist with the National Institutes of Health.

But Manolio and some of the other researchers caution that they are not yet recommending that doctors routinely give their patients a preventative carotid artery ultrasound.

"We're talking about tenths-of-a-millimeter difference in thicknesses of the carotid wall, which is like the thickness of a human hair," Manolio said. "Those kinds of things need to be measured very carefully and in a very standardized way.

"So this isn't something we feel can just go out and be applied willy-nilly. It really needs to be done in a careful way."

Until a practical and effective way to use ultrasound tests can be developed, doctors will continue to listen to the carotid arteries with a stethoscope when older people come in for a physical, ordering an ultrasound only if they hear something suspicious.

Medical Correspondent Elizabeth Cohen contributed to this report.