Clogged Neck Artery May Warn Of Heart Attack As Well As Stroke

Coronary heart disease is characterized by atherosclerosis -- accumulations of fat, cholesterol and other cells in the blood vessels of the heart. If these accumulations, known as plaque, rupture, a heart attack may result.

Previous studies have reported that individuals with atherosclerosis in their carotid arteries are likely to have coronary heart disease. This study was designed to refine this association and determine whether the severity of atherosclerosis in the carotid arteries correlated with the severity of coronary heart disease, according to the study's lead author, Ioannis Kallikazaros, M.D., associate director in cardiology at Hippokration Hospital in Athens, Greece.

The Greek team studied 225 people with chest pain who had been referred to Hippokration Hospital to determine if they had heart disease. Study participants, none of whom had been previously diagnosed with coronary heart disease, ranged in age from 35 to 77 years, with an average age of 58.

Patients underwent angiography, an imaging procedure in which a dye is injected into the artery to the heart to provide an X-ray of the blood vessels of the heart. Each person received noninvasive ultrasound tests of the carotid arteries to search both the left and right sides, and branches, for obstructions.

Researchers found that severe atherosclerosis in the carotid arteries was related to severe coronary heart disease. Conversely, normal carotid arteries indicated the person had no severe coronary heart disease, says Kallikazaros.

In the study, 39 percent of the study group had severe heart disease. In 31 percent of these 88 individuals, the atherosclerotic obstructions were severe -- greater than 50 percent -- in the carotid arteries. Among the 54 patients who had both severe heart disease and impaired pumping power -- a major predictor of heart attack -- 46.3 percent also had severe atherosclerosis in the carotid arteries.

The study findings have practical applications because obstructions in the carotid artery can be viewed with ultrasound, a technique less invasive than those required for viewing the heart.

"Because ultrasound is noninvasive, it is a safe and valuable way to obtain information about the carotid blood vessels that may predict the presence of heart disease," Kallikazaros says.

Ultrasound may also be useful for identifying individuals who are at high risk of suffering a stroke following cardiac bypass surgery. If carotid artery obstruction is found, treatments such as endarterectomy as well as anticoagulants or blood-thinning drugs, can be given to reduce the risk of a stroke following the heart surgery, adds Kallikazoros.

Kallikazaros and his colleagues assigned patients to one of five groups categorizing the severity of the atherosclerosis in both their carotid and coronary arteries.

The carotid artery classifications were: 1) no sign of plaque; 2) 2 to 15 percent artery obstruction; 3) 16 to 49 percent artery obstruction; 4) 50 to 79 percent artery obstruction; and 5) 80 to 100 percent artery obstruction.

The coronary artery classifications were based on the number of blood vessels that had obstructions. Coronary heart disease was defined as greater than 50 percent obstruction in at least one major artery.

Study findings showed that 18 percent of the 225 patients with heart disease had 50 percent or more obstruction of their left or right carotid artery and 88 percent had some degree of obstruction in their heart arteries. Heart disease increased from 17 percent in people without obstructions in the carotid artery to 46 percent in those with obstructions of greater than 75 percent in at least one major artery.

Co-authors are Costas Tsioufis, M.D.; Skevos Sideris, M.D.; Christodoulos Stefanadis, M.D.; and Pavlos Toutouzas, M.D.