Brenner L D, Caputo G R, Mostbeck G, Steiman D, Dulce M, Cheitlin M D, O'Sullivan M, Higgins C B
Department of Radiology, University of California Medical Center, San Francisco.
J Am Coll Cardiol. 1992 Nov 1;20(5):1246-50. doi: 10.1016/0735-1097(92)90384-y.
The purpose of this study was to evaluate the ability of velocity-encoded nuclear magnetic resonance (NMR) imaging to quantify left to right intracardiac shunts in patients with an atrial septal defect.
Quantification of intracardiac shunts is clinically important in planning therapy.
Velocity-encoded NMR imaging was used to quantify stroke flow in the aorta and in the main pulmonary artery in a group of patients who were known to have an increased pulmonary to systemic flow ratio (Qp/Qs). The velocity-encoded NMR flow data were used to calculate Qp/Qs, and these values were compared with measurements of Qp/Qs obtained with oximetric data derived from cardiac catheterization and from stroke volume measurements of the two ventricles by using volumetric data from biphasic spin echo and cine NMR images obtained at end-diastole and end-systole.
Two independent observers measured Qp/Qs by using velocity-encoded NMR imaging in 11 patients and found Qp/Qs ranging from 1.4:1 to 3.9:1. These measurements correlated well with both oximetric data (r = 0.91, SEE = 0.35) and ventricular volumetric data (r = 0.94, SEE = 0.30). Interobserver reproducibility for Qp/Qs by velocity-encoded NMR imaging was good (r = 0.97, SEE = 0.20).
Velocity-encoded NMR imaging is an accurate and reproducible method for measuring Qp/Qs in left to right shunts. Because it is completely noninvasive, it can be used to monitor shunt volume over time.
本研究旨在评估速度编码核磁共振（NMR）成像对房间隔缺损患者心内左向右分流进行定量分析的能力。
心内分流的定量分析在治疗方案规划中具有重要临床意义。
对一组已知肺循环与体循环血流量比值（Qp/Qs）升高的患者，采用速度编码NMR成像来定量分析主动脉和主肺动脉的每搏血流量。利用速度编码NMR血流数据计算Qp/Qs，并将这些值与通过心导管检查获得的血氧测定数据以及利用舒张末期和收缩末期双相自旋回波和电影NMR图像的容积数据测量两个心室的每搏量所得到的Qp/Qs测量值进行比较。
两名独立观察者通过速度编码NMR成像对11例患者的Qp/Qs进行测量，发现Qp/Qs范围为1.4:1至3.9:1。这些测量值与血氧测定数据（r = 0.91，标准误 = 0.35）和心室容积数据（r = 0.94，标准误 = 0.30）均具有良好的相关性。速度编码NMR成像测量Qp/Qs的观察者间重复性良好（r = 0.97，标准误 = 0.20）。
速度编码NMR成像是一种准确且可重复的测量左向右分流中Qp/Qs的方法。由于它完全无创，可用于长期监测分流量。
