Association between carotid intima-media thickness and aortic arch plaques

Large aortic arch plaques are associated with ischemic stroke. Carotid intima-media thickness (CIMT) is a marker of subclinical atherosclerosis and a strong predictor of cardiovascular disease and stroke. The association between CIMT and aortic arch plaques has been studied in patients with strokes, but not in the general population. The aim of this study was to investigate this association in an elderly asymptomatic cohort and to assess the possibility of using CIMT to predict the presence or absence of large aortic arch plaques.

Stroke-free control subjects from the Aortic Plaque and Risk of Ischemic Stroke (APRIS) study underwent transesophageal echocardiography and high-resolution B-mode ultrasound of the carotid arteries. CIMT was measured at the common carotid artery, bifurcation, and internal carotid artery. The association between CIMT and aortic arch plaques was analyzed using multivariate regression models. The positive and negative predictive values of CIMT for large (>or=4 mm) aortic arch plaques were calculated.

Among 138 subjects, large aortic arch plaques were present in 35 (25.4%). Only CIMT at the bifurcation was associated with large aortic arch plaques after adjustment for atherosclerotic risk factors (P=.007). The positive and negative predictive values of CIMT for aortic arch plaque>or=4 mm at the bifurcation above the 75th percentile (>or=0.95 mm) were 42% and 80%, respectively. The negative predictive value increased to 87% when the median CIMT value (0.82 mm) was used.

CIMT at the bifurcation is independently associated with aortic arch plaque>or=4 mm. Its strong negative predictive value for large plaques indicates that CIMT may be used as an initial screening test to exclude severe arch atherosclerosis in the general population.