BACKGROUND AND OBJECTIVES: This study was designed to formulate a method for the qualitative and quantitative measurements of aortic valve sclerosis (AVS) and to assess the relationship between this method and the degree of the carotid intima-media thickness (IMT) in neurologically asymptomatic patients. SUBJECTS AND METHODS: One hundred and seventeen patients (Male 43%, 57.9+/-13.1 years of age) were retrospectively studied. Only the right- and non-coronary cusps were analyzed. AVS (cusp thickness of > or =2.0 mm) severities were classified into two groups according to the thickness and presence of the restricted motion of the cusp : mild AVS : AVS of <3.0 mm in one cusp, without restricted motion ; severe AVS:AVS (+) in both cusps, AVS (+) and restricted motion in the same cusp, or a thickness > or =3.0 mm. The far wall IMT was measured at its thickest part in the distal 10.0 mm section of the common carotid artery. A protruding lesion with a far wall IMT > or =1.2 mm in the carotid bulb was defined as a plaque. RESULTS: According to the severity of AVS, there was a significant difference in the prevalence of an IMT > or =0.8 mm (38.7 vs. 50.0 vs. 75.8%, p0.005 for trend) and > or =1.0 mm (14.5 vs. 13.6 vs. 42.4%, p0.005 for trend), and a plaque (19.4 vs. 36.4 vs. 54.5%, p0.0005 for trend). The severity of AVS was independently correlated with an IMT > or =0.8 mm and IMT > or =1.0 mm, and with the presence of a plaque from a multiple logistic regression model. CONCLUSION: There was a significant association between AVS and the carotid IMT/plaque in relation to both in the presence and severity.