B‐flow sonographic demonstration for assessing carotid atherosclerosis in young patients with heterozygous familial hypercholesterolemia

Abstract

To determine whether bloodstream swirls detected with B-mode flow (B-flow) sonography at the region of the carotid bifurcation can predict the early progression of atherosclerosis, we prospectively examined the relationships between the size of bloodstream swirls as identified with B-flow sonography, the local mechanical behavior of the common carotid artery (CCA), and some cardiovascular risk factors in young patients with heterozygous familial hypercholesterolemia (FH). Thirty-eight young patients (mean age 25.8 +/- 14.1 years) with FH were evaluated for the following parameters: age, sex, body mass index, degree of dyslipidemia, presence of a plaque, intima-media thickness (IMT), elastic modulus (Ep) and internal diameter of the CCA via duplex scan, wall shear stress, maximal diameter of the bloodstream swirl (Sm) at bifurcation, maximal diameter of the CCA (Cm) at the level of the swirl's center, and diameter ratio (Sm/Cm) via B-flow sonography. Bloodstream swirls of varying size at the site of bifurcation were observed in all patients. Six (15.7%) out of 38 patients exhibited plaques at bifurcation. All plaques were located at the far wall and were in contact with the distal portion of the bloodstream swirl as observed with B-flow sonography. Univariate analysis revealed that Sm/Cm and Sm were positively correlated with age, presence of a plaque, IMT, and Ep and were negatively correlated with shear stress. Multivariate analysis revealed that Sm was significantly correlated with age (P < 0.01) and Ep (P < 0.05). Our results suggest that a bloodstream swirl visualized at the carotid bifurcation with B-flow sonography may be an indicator of a local mechanism for the age-related progression of atherosclerosis in young patients with FH.