使用与几何形状无关的三维数字彩色多普勒方法对瞬时流速和动态变化的有效瓣口面积进行量化：一项模拟二尖瓣反流的体外研究。

Quantification of instantaneous flow rate and dynamically changing effective orifice area using a geometry independent three-dimensional digital color Doppler method: An in vitro study mimicking mitral regurgitation.

作者信息

Li Xiaokui, Wanitkun Suthep, Li Xiang-Ning, Hashimoto Ikuo, Mori Yoshiki, Rusk Rosemary A, Hicks Shannon E, Sahn David J

机构信息

Clinical Care Center for Congenital Heart Disease, Portland, Oregon 97201, USA.

出版信息

J Am Soc Echocardiogr. 2002 Oct;15(10 Pt 2):1189-96. doi: 10.1067/mje.2002.124515.

DOI:10.1067/mje.2002.124515

PMID:12411904

Abstract

OBJECTIVE

Our study was intended to test the accuracy of a 3-dimensional (3D) digital color Doppler flow convergence (FC) method for assessing the effective orifice area (EOA) in a new dynamic orifice model mimicking a variety of mitral regurgitation.

BACKGROUND

FC surface area methods for detecting EOA have been reported to be useful for quantifying the severity of valvular regurgitation. With our new 3D digital direct FC method, all raw velocity data are available and variable Nyquist limits can be selected for computation of direct FC surface area for computing instantaneous flow rate and temporal change of EOA.

METHODS

A 7.0-MHz multiplane transesophageal probe from an ultrasound system (ATL HDI 5000) was linked and controlled by a computer workstation to provide 3D images. Three differently shaped latex orifices (zigzag, arc, and straight slit, each with cutting-edge length of 1 cm) were used to mimic the dynamic orifice of mitral regurgitation. 3D FC surface computation was performed on parallel slices through the 3D data set at aliasing velocities (14-48 cm/s) selected to maximize the regularity and minimize lateral dropout of the visualized 3D FC at 5 points per cardiac cycle. Using continuous wave velocity for each, 3D-calculated EOA was compared with EOA determined by using continuous wave Doppler and the flow rate from a reference ultrasonic flow meter. Simultaneous digital video images were also recorded to define the actual orifice size for 9 stroke volumes (15-55 mL/beat with maximum flow rates 45-182 mL/s).

RESULTS

Over the 9 pulsatile flow states and 3 orifices, 3D FC EOAs (0.05-0.63 cm(2)) from different phases of the cardiac cycle in each pump setting correlated well with reference EOA (r = 0.89-0.92, SEE = 0.027-0.055cm(2)) and they also correlated well with digital video images of the actual orifice peak (r = 0.97-0.98, SEE = 0.016-0.019 cm(2)), although they were consistently smaller, as expected by the contraction coefficient.

CONCLUSION

The digital 3D FC method can accurately predict flow rate, and, thus, EOA (in conjunction with continuous wave Doppler), because it allows direct FC surface measurement despite temporal variability of FC shape.

摘要

目的

本研究旨在测试一种三维（3D）数字彩色多普勒血流会聚（FC）方法在模拟各种二尖瓣反流的新型动态瓣口模型中评估有效瓣口面积（EOA）的准确性。

背景

据报道，用于检测EOA的FC表面积方法可用于量化瓣膜反流的严重程度。使用我们新的3D数字直接FC方法，所有原始速度数据均可用，并且可以选择可变的奈奎斯特极限来计算直接FC表面积，以计算瞬时流速和EOA的时间变化。

方法

将超声系统（ATL HDI 5000）的7.0-MHz多平面经食管探头与计算机工作站连接并由其控制，以提供3D图像。使用三个不同形状的乳胶瓣口（锯齿形、弧形和直缝形，每个瓣口的前沿长度为1 cm）来模拟二尖瓣反流的动态瓣口。在每个心动周期的5个时间点，对通过3D数据集的平行切片进行3D FC表面积计算，选择混叠速度（14-48 cm/s）以最大化可视化3D FC的规则性并最小化横向缺失。对于每个瓣口，将3D计算的EOA与使用连续波多普勒和参考超声流量计的流速确定的EOA进行比较。还记录了同步数字视频图像，以定义9个搏出量（15-55 mL/搏，最大流速45-182 mL/s）的实际瓣口大小。

结果

在9种搏动血流状态和3个瓣口的情况下，每个泵设置中心动周期不同阶段的3D FC EOA（0.05-0.63 cm²）与参考EOA相关性良好（r = 0.89-0.92，SEE = 0.027-0.055 cm²），并且它们与实际瓣口峰值的数字视频图像也相关性良好（r = 0.97-0.98，SEE = 0.016-0.019 cm²），尽管正如收缩系数所预期的那样，它们始终较小。