在 vena contracta 的功率-速度积分:一种用于直接量化反体积流量的新方法
T Buck1, R A Mucci, J L Guerrero
1Cardiac Ultrasound Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
Circulation
|August 30, 2000
概括
这项研究引入了一种新的多普勒功率原理,以准确量化反流. 静脉收缩处的功率-速度积分克服了当前用于流量测量的非侵入性多普勒技术的局限性.
科学领域:
- 心血管成像 - 心血管成像
- 血液动力学 血液动力学
- 医学物理 医学物理
背景情况:
- 使用多普勒反的非侵入性量化是有限的,因为它测量的是速度,而不是流量.
- 反向分散的多普勒功率与声化血液体积成比例,这表明功率乘以速度可能接近流速.
- 之前的研究表明,这一原理仅限于层状流,而不是乱的反喷流.
研究的目的:
- 为了测试这个假设,多普勒功率原理可以应用于近端 vena contracta,其中流量是层状的.
- 确定功率乘以速度积分与流量线性变化,其时间积分与冲量 (SV) 线性变化.
主要方法:
- 在实验室测试中,通过各种孔进行稳定和脉动的流动.
- 在体内血液动力学研究中,直接视觉记录了 mitra regurgitant SV (MRSV).
- 对患者的MRSV与MRI和3D回声测量进行比较.
主要成果:
- 计算和实际流量和SV in vitro之间的良好相关性 (r=0.99).
- 在体内 (r=0.98) 和患者 (r=0.98) 中MRSV的高相关性.
- 在所有测试条件下,在计算和实际SV中观察到的最小误差.
结论:
- 在 vena contracta 的功率-速度积分准确地测量了反的流量.
- 这种方法克服了现有的多普勒技术的局限性,用于非侵入性流量定量.
- 这些发现支持一种新的直接测量方法,用于反流.
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