Relationship of the Intima-Media Thickness of the Common Carotid Artery, Atherosclerotic Plaques on the Carotid Beds and Manifest Peripheral Vascular Disease to Coronary Artery Disease

Overview

Background.
Concomitant occurence of carotid atherosclerosis, coronary artery disease (CAD) and peripheral vascular disease (PVD) has been described in a number of studies. The objective of the present trial was to assess the degree of correlation between atherosclerosis of the carotid beds as well as PVD and the extent of CAD. Methods and Results. Carotid morphologies of 170 patients in total (121 men, 49 women), ranging between 23 and 81 years in age were assessed ultrasonographically. Their carotid beds searched for plaques, stenoses and occlusions. In all patients intima-media thickness (IMT) of the common carotid artery (CCA) were measured ultrasonographically. In addition, case histories of PVD were taken. CAD was proved angiographically in 138 patients. Plaques in carotid beds were found in 98 patients, carotid artery stenoses >75 % were found in 4 patients whereas complete carotid occlusion was not detected in any patient. Clinically manifested PVD was found in 20 patients. A significant difference in IMT of the CCA was assessed by t-test between patients having and not having CAD (0.67 ± 0.16 mm vs. 0.87 ± 0.24 mm; P < 0.0001). The correlation between the IMT of the CCA and extent of CAD was weak (r = 0.30, p < 0.01). A positive correlation between carotid plaque occurrence and the number of CAD-affected arteries was statistically assessed (Trend test: P = 0.0001). The sensitivity of incidence of plaques on the carotid beds for prediction of CAD was 64%, the specificity 72%, the positive predictive value 91% and the negative predictive value 32%. The sensitivity of clinically manifested PVD for prediction of CAD was 15%, the specificity 100%, the positive predictive value 100% and the negative predictive value 21%. Conclusions. The authors confirmed a statistically significant but weak correlation between IMT of the CCA and severity of CAD. They found a positive trend between the occurrence of carotid plaques and the number of CAD-affected arteries. The presence of carotid plaques and clinically manifested PVD were confirmed as a reliable positive predictive factors for CAD.

Key words:
atherosclerosis of the carotid beds, coronary artery disease, peripheral vascular disease, ultrasound.