Männer J, Seidl W, Steding G
Abteilung Embryologie, Universität Göttingen, Germany.
Anat Embryol (Berl). 1997 Dec;196(6):435-45. doi: 10.1007/s004290050111.
Deficient connections (= isolation) of the innominate artery or the common carotid artery to the aorta are rare congenital anomalies of the human aortic arch complex that are usually associated with a patent vascular connection between the isolated artery and a pulmonary artery. In the present study we demonstrate chick fetuses with a corresponding anomaly, the isolation of the brachiocephalic artery. In our chick fetuses the left brachiocephalic artery did not arise from the aortic arch, but was connected to the pulmonary trunk proximal (upstream) to the patent left and right ductus arteriosus. These cases are of interest because the presence of a congenital pulmonary-systemic arterial connection proximal (upstream) to the ductus arteriosus cannot be explained by the traditional concept of the morphogenesis of the aortic arch complex. The development of the normal and abnormal branching patterns of the aortic arch arteries is traditionally explained by transformation of the primitive embryonic pharyngeal arch arterial system due to obliteration of some of its vascular segments. Based on this concept, the isolation of an aortic arch artery can be explained by obliteration of vascular segments proximal and distal to this artery, whereas its connection to a pulmonary artery can be explained only by deficient obliteration (persistence) of the distal portion of the right or left sixth pharyngeal arch artery. The connecting "vascular segment" between an isolated aortic arch artery and the pulmonary circulation, therefore, is traditionally interpreted as a patent ductus arteriosus. The formal pathogenesis of congenital pulmonary-systemic arterial connections proximal (upstream) to the ductus arteriosus is discussed. The presented cases of isolation of the brachiocephalic artery are explained by disturbances in the partition of the embryonic aortic sac, possibly due to abnormal development of the "cardiac" neural crest.
无名动脉或颈总动脉与主动脉连接缺失（即孤立）是人类主动脉弓复合体罕见的先天性异常，通常与孤立动脉和肺动脉之间存在开放的血管连接有关。在本研究中，我们展示了具有相应异常的鸡胚，即头臂动脉孤立。在我们的鸡胚中，左头臂动脉并非起源于主动脉弓，而是连接到左、右动脉导管开放处近端（上游）的肺动脉干。这些病例很有意思，因为动脉导管近端（上游）存在先天性肺 - 体循环动脉连接无法用主动脉弓复合体形态发生的传统概念来解释。主动脉弓动脉正常和异常分支模式的发育传统上是通过原始胚胎咽弓动脉系统因部分血管段闭塞而发生转变来解释的。基于这一概念，主动脉弓动脉的孤立可以通过该动脉近端和远端血管段的闭塞来解释，而其与肺动脉的连接只能通过右或左第六咽弓动脉远端部分闭塞不足（持续存在）来解释。因此，孤立的主动脉弓动脉与肺循环之间的连接“血管段”传统上被解释为开放的动脉导管。本文讨论了动脉导管近端（上游）先天性肺 - 体循环动脉连接的正式发病机制。所呈现的头臂动脉孤立病例是由胚胎主动脉囊分隔紊乱所解释的，这可能是由于“心脏”神经嵴发育异常所致。
