Carotid and aortic stiffness in patients with heterozygous familial hypercholesterolemia

Abstract

Background: The role of plasma cholesterol in impairing arterial function and elasticity remains unclear. We evaluated arterial stiffness, measured locally in the common carotid artery by high-resolution echo-tracking, and aortic stiffness, using carotid-femoral pulse wave velocity (PWV) (the "gold-standard" measurement of arterial stiffness), in treatment-naive patients with heterozygous familial hypercholesterolemia (FH). Methods: The study included 66 patients with FH (10-66 years old) and 57 first-degree relatives without FH (11-61 years old). Carotid-femoral PWV was determined by SphygmoCor (AtCor, Australia). The parameters of carotid stiffness β-index, Peterson elastic modulus and local PWV were assessed with regard to the common carotid artery at a distance of 1cm from the bifurcation (AlokaProsound Alpha7, Japan). Results: FH patients showed significantly higher β-index (6.3(4.8-8.2) vs. 5.2(4.2-6.4), p = 0.005), Ep (78(53-111) kPa vs. 62(48-79) kPa, p = 0.006), local PWV (5.4(4.5-6.4) m/c vs. 4.7 (4.2-5.4) m/c, p = 0.005), but comparable values of carotid-femoral PWV (6.76(7.0-7.92) m/c vs. 6.48(6.16-7.12) m/c, p = 0.138). Carotid arteries and the aorta stiffened with age in patients with FH, but after 30 years, carotid arteries stiffened more significantly than the aorta. Conclusions: Our study demonstrated that treatment-naive patients with FH had stiffer carotid arteries than their relatives, but showed no difference in aortic stiffness. We also found out that the rate of reduction of elasticity of the aorta and carotid arteries in FH patients varies: it is observed earlier in carotid arteries than in the aorta.