Arterial mechanical changes in children with familial hypercholesterolemia

Citation
Y. Aggoun et al., Arterial mechanical changes in children with familial hypercholesterolemia, ART THROM V, 20(9), 2000, pp. 2070-2075
Citations number
33
Categorie Soggetti
Cardiovascular & Hematology Research
Journal title
ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY
ISSN journal
10795642 → ACNP
Volume
20
Issue
9
Year of publication
2000
Pages
2070 - 2075
Database
ISI
SICI code
1079-5642(200009)20:9<2070:AMCICW>2.0.ZU;2-9
Abstract
Atherosclerosis is preceded by a phase of changes ill the arterial wall tha t could have functional consequences even before the appearance of atheroma tous changes. We hypothesized that early alterations of the mechanical prop erties of the arterial wall could precede clinical and echographic modifica tions. We used an automatic, computerized, ultrasonic procedure to evaluate geometric and mechanical characteristics of the common carotid artery (CCA ) in normotensive children with primary familial class IIA hypercholesterol emia (FH; n=30; mean+/-SD age, 11+/-2: years old; mean+/-SD systolic/diasto lic blood pressure, 109+/-9/55+/-7 mm Hg) These subjects were compared with age-matched, nonobese control subjects (n=27; 11+/-3 :years old; 112+/-10/ 55+/-7 mm Hg). Noninvasive ultrasonic measurements were performed by the sa me investigator to measure the CCA luminal systolic and diastolic diameters and intima-media thickness (IMT). The cross-sectional compliance, cross-se ctional distensibility, and the incremental elastic modulus of the CCA wall were then calculated. Fin:ally, we assessed the degree of reactive hyperem ia in the brachial artery produced after distal cuff occlusion and release. The changes in brachial arterial diameter in response to reactive hyperemi a (endothelium-dependent dilation) and to glyceryltrinitrate (endothelium-i ndependent dilation) were then measured. In patients with FH, we observed a significant reduction of systodiastolic variations in diameter (by 20%, P< 0.001) without a significant difference in IMT. Cross-sectional compliance and cross-sectional distensibility were significantly reduced in FH subject s (by 15%, P<0.05 and 19%, P<0.01, respectively). In parallel, the incremen tal elastic modulus was significantly increased (by 27%, P<0.01) in childre n with FH. No correlation was evident between the carotid incremental modul us and either IMT or plasma low density lipoprotein cholesterol level, Ther e was no difference in diameter of the brachial artery at rest in control a nd FH subjects (3.0+/-0.5 versus 3.0+/-0.4 mm). The reactive hyperemia and glyceryltrinitrate dilation were also similar in the 2 groups. However, the flow-mediated dilation of the brachial artery was smaller in the FH subjec ts (4.2+/-2.9%) than in controls (9.0+/-3.1%, P<0.001). In FH, endothelium- dependent dilation was negatively correlated with the plasma low density li poprotein cholesterol level (P<0.04). These results indicate that increased stiffness of the CCA wall in children with FH is independent of blood pres sure and could be related to endothelial dysfunction. Thus, alterations in CCA wall mechanics could be early and easily,measurable markers of atheroma tous changes in the arterial wall.