Noninvasive assessment of artery wall properties in children aged 4-19 years

The vessel wall properties of the common carotid artery were noninvasively studied in 53 normotensive, presumed normal boys of various ages (4-19 yr) with the use of a multigate pulsed Doppler system. This device allows the on-line recording of velocity profiles and the relative changes in carotid artery diameter during the cardiac cycle. From the width of these profiles, the internal diameter of the carotid artery can be determined. With the use of internal carotid artery diameter, relative changes in carotid artery diameter during the cardiac cycle, and pulse pressure the pulse pressure, as measured in the brachial artery, the distensibility coefficient and the cross-sectional compliance were calculated. The children were allotted to three different age groups: group I (4-10 yr), group II (11-14 yr), and group III (15-19 yr). In the older children (group III) the systolic arterial pressure and the pulse pressure were significantly higher than in groups I and II. The carotid artery diameter was significantly larger and the distensibility coefficient was significantly smaller in group III than in groups I and II. The cross-sectional compliance was not significantly different in the age groups, which can be explained by the larger artery diameter in the older age group. The findings indicate that the carotid artery wall is less distensible in adolescents than in younger children. The subjects in group III showed similar carotid artery wall properties as the young adults (aged 20-34 yr) in a previous study. Therefore, it is likely that in adolescents the vascular system can be considered as mature as far as the arterial wall properties are concerned.