在Fontan生理学中的外周血管适应和正静性耐受性
Usha S Krishnan1, Indu Taneja, Michael Gewitz
1Department of Pediatric Cardiology, New York Medical College, Valhalla, NY 10595, USA. usha_krishnan@nymc.edu
Circulation
|October 21, 2009
概括
患有Fontan循环的患者适应更高的静脉压力,具有更硬的血管和减少的液体转移,改善直立耐受性. 这些变化有助于维持血液在Fontan循环中的回流.
科学领域:
- 心血管生理学心血管生理学
- 儿童心脏病学 儿童心脏病学
- 血管生物学 血管生物学
背景情况:
- 丰坦循环依赖于高静脉压力,以有效的静脉回流.
- 系统静脉压的慢性增加可能会诱导适应性血管变化,特别是在直立姿势中.
研究的目的:
- 调查后Fontan患者区域和外围血管的适应性变化.
- 了解这些适应如何维持心脏输出,特别是当直立时.
主要方法:
- 对比了9名Fontan后患者 (13-24岁) 与6名年龄/性别匹配的对照组.
- 利用张力计和阻抗缩图来检测周围循环和血液体积.
- 通过头向上倾斜测试评估循环反应.
主要成果:
- 丰坦患者的小腿容量较低,静脉静脉压较高.
- 在Fontan患者中观察到腿部动脉阻力增加和微血管过压力升高.
- 与对照人群相比,Fontan患者在抬头倾斜时显示了保留的支柱状动脉流和的支柱状动脉阻力增加.
结论:
- 降低静脉合规性和增加过门似乎是Fontan循环中的适应机制.
- 补偿良好的Fontan患者由于流体转移减少和血管阻力增加而表现出优异的静态耐受性.
- 增加静脉硬性和改变的脊柱容量可能是保持静脉回归的适应性策略,当在Fontan患者站立时.
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