Ostrem Joseph D, Evanoff Nicholas, Kelly Aaron S, Dengel Donald R
Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN 55455.
Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN 55455.
J Clin Ultrasound. 2015 Oct;43(8):495-501. doi: 10.1002/jcu.22267. Epub 2015 Mar 20.
When assessing vasomotor endothelial function by reactive hyperemia, the brachial artery, in some individuals, constricts immediately before beginning to dilate following cuff release. We call this response high-flow-mediated constriction (H-FMC). The aim of this study was to describe the rate of the H-FMC during reactive hyperemia in children and adolescents throughout a range of body mass index (BMI) values, and to investigate differences in flow-mediated dilation (FMD), cardiovascular, and anthropometric measures between subjects with and without H-FMC.
FMD was assessed in 136 children and adolescents (61 male, 75 female; 13 ± 3 years) by sonographic imaging of the brachial artery. H-FMC was characterized as the lowest point from the baseline brachial artery diameter immediately following reactive cuff release. Independent t tests were used to compare subjects with and without H-FMC.
H-FMC was observed in 91 of the 136 participants (66.9%). No significant difference was found between H-FMC and non-H-FMC subjects for age (p = 0.602), gender (p = 0.767), height (p = 0.227), or weight (p = 0.171). BMI percentile was nonsignificantly higher (91.8 ± 4.9th versus 84.6 ± 22.8th percentile, p = 0.057) and FMD was significantly lower (5.43 ± 3.41% versus 8.05 ± 3.97%, p < 0.001) in H-FMC than in non-H-FMC subjects. Adding H-FMC to FMD produced no significant difference between H-FMC and non-H-FMC individuals (8.03 ± 3.27% versus 8.05 ± 3.97%, p = 0.977).
Approximately 67% of participants demonstrated an H-FMC during reactive hyperemia. BMI percentile was nonsignificantly higher and FMD was significantly lower in children and adolescents who displayed this phenomenon.
在通过反应性充血评估血管运动内皮功能时，在某些个体中，肱动脉在袖带松开后开始扩张之前会立即收缩。我们将这种反应称为高流量介导的收缩（H-FMC）。本研究的目的是描述儿童和青少年在一系列体重指数（BMI）值范围内反应性充血期间H-FMC的发生率，并调查有和没有H-FMC的受试者之间在血流介导的扩张（FMD）、心血管和人体测量指标方面的差异。
通过肱动脉超声成像对136名儿童和青少年（61名男性，75名女性；13±3岁）进行FMD评估。H-FMC被定义为反应性袖带松开后肱动脉直径从基线的最低点。使用独立t检验比较有和没有H-FMC的受试者。
136名参与者中有91名（66.9%）观察到H-FMC。H-FMC组和非H-FMC组在年龄（p=0.602）、性别（p=0.767）、身高（p=0.227）或体重（p=0.171）方面没有显著差异。H-FMC组的BMI百分位数略高（第91.8±4.9百分位与第84.6±22.8百分位，p=0.057），FMD显著较低（5.43±3.41%与8.05±3.97%，p<0.001）。将H-FMC添加到FMD中，H-FMC组和非H-FMC组个体之间没有显著差异（8.03±3.27%与8.05±3.97%，p=0.977）。
约67%的参与者在反应性充血期间表现出H-FMC。出现这种现象的儿童和青少年的BMI百分位数略高，FMD显著较低。
