Noninvasive measurements that relate to the extent and severity of coronary atherosclerosis have long been sought for clinical screening of patients with chest pain syndromes and for use in clinical trials. Intima-media thickeness (IMT) of the carotid artery has been suggested to be associated with coronary artery atherosclerosis. In this study, we tried to assess the relation of carotid artery atherosclerosis by B-mode ultrasonography with presence and severity of coronary artery disease.

We studied 57 patients (36 men, 21 women) with ischemic heart disease, mean age 65±8 yrs (48 to 83 yrs), who underwent both coronary angiography and carotid ultrasonography with 10 MHz transducer. The patients who had received revascularization procedure were excluded. We classified the patients into two groups, the control group without significant coronary stenosis (18 patients) and the coronary artery disease (CAD) group (39 patients) with significant luminal stenosis (> or =50%). The CAD group was divided into single vessel disease group (SVD, 19 patients) and multivessel disease group (MVD, 20 patients). IMT was measured in far wall of common carotid artery (CCA) at 10 mm proximal to carotid bulb and abnormal IMT was defined if the measurement was greater than mean IMT+2SD of control group. Serum total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), triglyceride (TG), Lipoproteinp (a)(Lp(a)) were measured and history of hypertension, diabetes mellitus, and smoking were investigated.

A significant difference in IMT of the CCA was found between control and CAD group (0.76±0.09 mm vs. 0.97±0.20 mm; p<0.0001). Also a significant difference in the number of atherosclerotic plaque was found between the two groups (control; 0.67±1.14 vs. CAD; 1.87±1.75; p<0.005). In the CAD group, both mean IMT and numbers of athero-sclerotic plaque tended to increase in MVD group compared with SVD group (1.03 mm vs. 0.91 mm; p=NS, 2.65 vs. 1.05; p<0.05). The sensitivity of IMT for prediction of significant CAD was 66.7%, the specificity 83.3%, the positive predictive value 89.7%, and the negative predictive value 53.6%. The sensitivity of plaque presence on the carotid artery for prediction of CAD was 71.8%, the specificity 61.3%, the positive predictive value 80.3% and the negative predictive value 50.5%. Among risk factor, diabetes mellitus and Lp (a) were correlated well with IMT of CCA, Hypertension was correlated with atherosclerotic plaque. History of smoking was correlated with coronary artery disease.

Increases in IMT and plaque of the carotid artery, as measured noninvasively by ultrasonography, can be used as a predictor of significant coronary artery stenosis.