Fetal Cardiac Unit, Monash Medical Centre, Clayton, Victoria, Australia.
Ultrasound Obstet Gynecol. 2013 Feb;41(2):168-71. doi: 10.1002/uog.11171.
Traditionally transposition of the great arteries (TGA) is suggested by bifurcation of the great vessel arising from the posterior ventricle and the parallel course of the great vessels as they leave the heart. These findings may be difficult to demonstrate, requiring additional fetal echocardiographic features to indicate TGA. In this study, we investigated a new marker of TGA, namely rightward convexity of the great vessel arising from the anterior ventricle.
We reviewed fetal studies from 2006 to 2010 in which an antenatal diagnosis of TGA was confirmed postnatally. We specifically viewed images obtained by scanning the great vessel arising from the anterior ventricle cranially to the superior mediastinum at the level of the three vessels and trachea view and compared them with similar views in normal hearts.
In 21 cases of confirmed TGA, the great vessel arising from the anterior ventricle (aorta) coursing cranially demonstrated an abnormal convexity to the right. This was in contrast to convexity to the left or lack of convexity of the great vessel (pulmonary artery) arising from the anterior ventricle in fetuses with a normal heart. In two fetuses rightward vessel convexity from the anterior ventricle was the clue on the initial scan suggesting TGA, which was subsequently confirmed. In addition, only two vessels, the superior vena cava and aorta, were demonstrated in fetuses with TGA, the pulmonary artery and ductus arteriosus lying below (caudal to) the transverse arch.
Noting the rightward convexity of the great vessel arising from the anterior ventricle may aid in the prenatal diagnosis of TGA. Furthermore, the relative simplicity of this sign may make it valuable in fetal screening for this cardiac defect.
传统上认为大动脉转位（TGA）的特征为发自后心室的大血管分支以及大血管离开心脏时的平行走行。这些发现可能难以显示，需要额外的胎儿超声心动图特征来指示 TGA。在本研究中，我们研究了 TGA 的一个新标志物，即发自前心室的大血管的右凸。
我们回顾了 2006 年至 2010 年期间经产前诊断为 TGA 并在产后得到证实的胎儿研究。我们特别查看了从前心室向头侧扫描获得的发自前心室的大血管图像，直至三血管和气管切面水平，并将其与正常心脏的类似图像进行比较。
在 21 例确诊的 TGA 病例中，发自前心室（主动脉）的大血管向头侧走行时表现出异常的向右凸。这与正常心脏胎儿发自前心室的大血管（肺动脉）向左凸或无凸形成对比。在 2 例胎儿中，发自前心室的右向血管凸是提示 TGA 的初始扫描线索，随后得到证实。此外，仅在 TGA 胎儿中显示了两条血管，即上腔静脉和主动脉，肺动脉和动脉导管位于（横弓下方）。
注意发自前心室的大血管的右凸可能有助于 TGA 的产前诊断。此外，该征象相对简单，可能对胎儿筛查这种心脏缺陷有价值。
