戈林公式和连续性方程膜面积的依赖性在膜大动脉狭窄时的跨膜体积流速
I G Burwash1, D D Thomas, M Sadahiro
1Department of Medicine, University of Washington, Seattle 98195.
Circulation
|February 1, 1994
概括
戈林和连续性方程区域在大动脉狭窄时都是流量依赖的. 这些计算的膜面积随着跨膜体积流速的变化而变化,影响狭窄的严重程度评估.
科学领域:
- 心血管生理学心血管生理学
- 医疗成像医学成像
- 生物医学工程 生物医学工程
背景情况:
- 众所周知,由戈林公式衍生的门面积与跨膜体积流速波动.
- 使用多普勒心声学计算的连续性方程面积是狭窄症严重性的常见指标.
- 连续性方程面积的流量依赖性仍然不清楚.
研究的目的:
- 为了研究变化的跨膜体积流速对大动脉膜区域的影响.
- 通过戈林公式计算的门面积的流量依赖性与连续性方程进行比较.
- 评估这些计算在慢性膜大动脉狭窄症的狗模型中.
主要方法:
- 使用了一种慢性膜大动脉狭窄症的狗模型.
- 通过使用盐水或多布他明输注来操纵膜外体积流速.
- 血液动力学,大动脉体积流速和多普勒回声数据同时测量.
- 门面积是使用戈林公式和连续性方程计算的.
主要成果:
- 戈林和连续性方程区域都表现出显著的变化,其体积流速发生了变化 (P < .0001).
- 戈林面积与流速有很强的线性相关性 (中位数r = .88),而连续性方程面积的相关性较弱 (中位数r = .51).
- 这两种方法都揭示了流量依赖的膜区域,表明狭窄症的严重程度受流量的影响.
结论:
- 戈林和连续性方程面积都是大动脉狭窄的流量依赖指数.
- 计算的门面积与跨门体积流速线性变化.
- 在使用膜面积测量来评估大动脉狭窄的血液动力学严重程度时,考虑流速至关重要.
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