Flow-Mediated Dilation of Brachial Artery in Children and Adolescents With Essential Arterial Hypertension

Objective: Flow-mediated dilation (FMD) of brachial artery represents non-invasive method that evaluates the endothelial function in macrovasculature, and some studies suggest that FMD possesses an independent prognostic value for the occurrence of future cardiovascular events. It is well accepted that hypertension is associated with impaired endothelium-dependent vascular response in adult patients and reduced vasodilation is considered an initial sign of functional alterations that precede the morphological changes. However, there is a lack of data on hypertension-related endothelial (dys)function in hypertensive children. Thus, present study aimed to evaluate macrovascular endothelium-dependent reactivity. Design and method: 52 children and adolescents were enrolled in this observational cross-sectional study; 26 healthy normotensive (NT) and 26 with diagnosed essential arterial hypertension (HT), both sexes, 9-17 years old. In addition to anthropometric, and hemodynamic measurements, the endothelial function of brachial artery was evaluated using a method based on the assessment of flow-mediated dilation. Statistical analysis was conducted by Mann-Whitney U test (between groups) and an analysis of covariance (ANCOVA) adjusted for age, gender, BMI and lipid parameters was performed (p< 0.05 was considered statistically significant). Results: Although body mass index (BMI) was significantly higher in children and adolescents with essential arterial hypertension compared with normotensive, waist-to-hip (WHR) ratios were similar in both groups. Systolic (SBP), diastolic (DBP) and mean (MAP) arterial blood pressure were significantly higher in the HT compared to the NT group, while there were no difference in heart rate between groups. Endothelium-dependent vasodilation of the brachial artery assessed by ultrasound flow-mediated dilation was significantly decreased in hypertensive children compared to normotensive healthy children (FMD % of dilation NT 10.22 7.00-17.31 vs. HT 8.68 6.14-12.98). Conclusions: Even in childhood, essential arterial hypertension has an adverse effect on vascular function and significantly reduces the endothelium-dependent response of brachial artery, independently of age, gender, BMI and lipid parameters. (Trial Registration:NCT05109013)