Glass E C, Rahimian J, Hines H H
J Nucl Med. 1986 Aug;27(8):1282-92.
In principle, region of interest (ROI) selection should not affect the measurement of cardiac output by the first-pass technique with a radioactive intravascular indicator. Clinical application of the method requires that this theoretical hypothesis be tested. Sixty-eight left anterior oblique first-pass studies were acquired with a scintillation camera and computer using red blood cells labeled in vitro with 99mTc. Calculated mean cardiac output varied in the following order with respect to ROI: lung greater than right heart greater than left ventricle greater than whole heart (both ventricles) greater than aorta. Similar variations were observed in patients both with and without valvular regurgitation. Regions of interest over left ventricle or whole heart yielded the best correlations with cardiac output by thermodilution (r = 0.96, 0.95, respectively, n = 28) as well as the smallest interobserver variations (r = 0.994, 0.995, respectively, n = 33). First-pass studies with [99mTc]red blood cells labeled in vitro can yield accurate, reproducible determinations of cardiac output provided that the effect of ROI selection is recognized and that regions are properly selected.
原则上，感兴趣区（ROI）的选择不应影响通过放射性血管内指示剂首过技术测量的心输出量。该方法的临床应用需要对这一理论假设进行检验。使用闪烁相机和计算机，对68例左前斜位首过研究进行了采集，这些研究使用的是经体外99mTc标记的红细胞。计算得出的平均心输出量随感兴趣区的变化顺序如下：肺大于右心大于左心室大于全心（两个心室）大于主动脉。在有和没有瓣膜反流的患者中均观察到类似的变化。左心室或全心的感兴趣区与热稀释法测量的心输出量相关性最佳（r分别为0.96、0.95，n = 28），并且观察者间差异最小（r分别为0.994、0.995，n = 33）。只要认识到感兴趣区选择的影响并正确选择区域，使用体外标记的[99mTc]红细胞进行首过研究就能准确、可重复地测定心输出量。
