Recently it was shown that subjects with aortic valve calcium (AVC) are at increased risk for future cardiovascular disease including stroke. We hypothesized that the increased risk of stroke may be due to an association with carotid artery atherosclerotic disease. Between 1995 and 1999 our laboratory made a diagnosis of AVC without significant stenosis in 3,949 patients. Of those, 279 patients without other cardiac structural exclusion criteria (148 men and 131 women; mean age 73 +/- 9 years, range 45 to 90) underwent carotid artery duplex ultrasound for various indications, and formed the study group. Age- and sex-matched patients without AVC (n = 277), who underwent carotid artery duplex ultrasound during the same period and for the same indications, served as the control group. Compared with the control group, the AVC group had a significantly higher prevalence of carotid stenosis (> 40% to 60%, 89% vs 78% [p < 0.001]; >60% to 80%, 43% vs 23% [p <0.001];and > 80% to 100%, 32%vs 14% [p < 0.001]). The AVC group had a similar, significantly higher prevalence of > or = 2-vessel disease and bilateral carotid stenosis (stenosis levels of > 20% to 40%, >40% to 60%, > 60% to 80%, and > 80% to 100%). In multivariate analysis, AVC, but not traditional risk factors, was the only independent predictor of severe carotid atherosclerotic disease (stenosis > 80% to 100%; p = 0.0001). Thus, there is a significant association between the presence of AVC and carotid atherosclerotic disease.