ASSOCIATION OF CORONARY-DISEASE WITH SEGMENT-SPECIFIC INTIMAL-MEDIAL THICKENING OF THE EXTRACRANIAL CAROTID-ARTERY

Background Several investigators have evaluated relations between risk factors and intimal-medial thickness (IMT) of the extracranial caroti d arteries and between IMT and clinical cardiovascular disease. Differ ent indexes of IMT have been used as referents. We compared the streng th of association of various IMT measurements with coronary artery dis ease as measured at coronary angiography. Methods and Results We quant ified the mean of the IMT for 12 sites of the extracranial carotid art eries (common carotid, bifurcation, internal carotid, near and far wal ls, and left and right sides [mean aggregate]) as well as for various combinations of sites (eg, segment-specific means, far walls only, max imum of any site) in 270 patients with or free of coronary artery dise ase. Models including age and all the indexes of IMT identified the me an aggregate as the only Variable independently associated with the st atus of coronary atherosclerosis for the group as a whole. Next most s trongly correlated was the mean common plus bifurcation. When classifi cation algorithms were tested for ability to correctly classify case p atients and control subjects, the mean bifurcation, mean common plus b ifurcation, and mean aggregate were most strongly related to case-cont rol status; however, the predictive power of the mean common was also strong. Conclusions These data support use of the mean aggregate extra cranial carotid IMT for correlation with the status of coronary athero sclerosis; however, the data also support use of the mean common plus bifurcation, since there is little increase in predictive power of the mean aggregate over this index. Use of the common carotid alone is al so justifiable and may be preferable for certain analyses.