Sonographic assessment of atherosclerotic and hypercholesterolemic artery using the echo-tracking technique in an animal model.

The purpose of this study was to ascertain the utility of sonography with the echo-tracking (ET) technique to assess vascular stiffness in rabbits with hypercholesterolemia and atherosclerosis. Grayscale sonography associated with the ET technique was used to measure the elastic modulus (Ep) of the aorta in cholesterol-fed rabbits (group T1, n = 44, for 4 weeks; group T2, n = 44, for 12 weeks) and normal control rabbits (group C1, n = 44; group C2, n = 44). The aortic Ep values and blood biochemical markers between groups were compared using analysis of covariance. Light and transmission electron microscopic evaluation were used to demonstrate atherosclerotic changes in the aorta. The Ep values of the aorta in group T1 and T2 rabbits were significantly higher than those of group C1 and C2 controls (88.74 +/- 27.99 and 100.96 +/- 24.81 vs 64.38 +/- 20.23 and 72.35 +/- 18.43, p = .124). Also, the Ep values of the aorta between group T1 and T2 rabbits were significantly different (p = .033). Light and transmission electron microscopy confirmed morphologic typical changes of aortic atherosclerosis in groups T1 and T2. Grayscale sonography with the ET method could be used to evaluate tissue elastic changes in arterial walls associated with atherosclerosis and hypercholesterolemia.