THURSDAY, May 8, 2008 (HealthDay News) -- That unusual, harsh sound a doctor can hear when passing a stethoscope over a main artery to the brain could indicate an increased risk of heart attack and death from heart disease and stroke, a new study finds.
The sound -- called a carotid bruit (pronounced brew-ee) -- is caused by turbulent blood flow due to buildup of fatty deposits in one of the two arteries that carry blood to the front and middle part of the brain. It is usually regarded as a possible indicator of increased risk of stroke.
Now an analysis of 22 studies finds that people with carotid bruits are more than twice as likely to have heart attacks or to die of cardiovascular disease. "The presence of a carotid bruit should heighten clinician concern for coronary heart disease," said the report by physicians at Walter Reed Army Medical Center in Washington, D.C.
The studies included 17,295 people who were followed for an average of four years. "In the four studies in which direct comparison of patients with and without bruits were possible, the odds ratio for myocardial infarction [heart attack] was 2.15 and for cardiovascular death 2.27," the report said.
The findings are published in the May 10 issue of The Lancet.
Using the presence of a bruit as an indicator of cardiovascular risk could be helpful, but "there are some unresolved questions about the usefulness of carotid bruit and prognosis," said Dr. Victor Aboyans, a cardiologist at Dupuytren University Hospital in Limoges, France, and co-author of an accompanying editorial in the journal.
"First, many of the patients who were studied already had cardiovascular disease, so what is the additional value of carotid bruit in such a case?" Aboyans asked. "The second issue is that some patients who don't have carotid bruit may have other evidence of cardiovascular disease."
Several studies have shown that starting preventive measures for stroke on the basis of screening for carotid bruit aren't useful, Aboyans said. Nevertheless, presence of carotid bruit could prompt physicians to be more aggressive in recommending measures to reduce the risk of cardiovascular disease, such as cholesterol reduction, he said.
Dr. Deepak Bhatt, associate director of the Cleveland Clinic Cardiovascular Coordinating Center, said, "The [study authors'] recommendation that they be even more aggressive with risk modification, that is good clinical judgment."
Physicians routinely listen for possible carotid bruits when doing a physical examination of people who are middle-aged or older, Bhatt noted.
Studies have shown that there's a link between the risk of stroke and of coronary heart disease, Bhatt said. "The core knowledge already exists," he said. "This study helps put a number on how high the risk is."
But the study raises some practical issues, Bhatt added. "One is whether, if a carotid bruit is found, to go ahead and do an ultrasound examination," he said. "I would say yes, but it is controversial. The U.S. Preventive Task Force recommends against routine ultrasound in general."
Learn what a carotid bruit is and what it might mean from the American Heart Association.