Abstract：
The development of a fully functional four-chambered heart is critically dependent on the correct formation of the structures that separate the atrial and ventricular chambers. Perturbation of this process typically results in defects that allow mixing of oxygenated and deoxygenated blood. Atrioventricular septal defects (AVSD) form a class of congenital heart malformations that are characterized by the presence of a primary atrial septal defect (pASD), a common atrioventricular valve (cAVV), and frequently also a ventricular septal defect (VSD). While AVSD were historically considered to result from failure of the endocardial atrioventricular cushions to properly develop and fuse, more recent studies have determined that inhibition of the development of other components of the atrioventricular mesenchymal complex can lead to AVSDs as well. The role of the dorsal mesenchymal protrusion (DMP) in AVSD pathogenesis has been well-documented in studies using animal models for AVSDs, and in addition, preliminary data suggest that the mesenchymal cap situated on the leading edge of the primary atrial septum may be involved in certain situations as well. In this chapter, we review what is currently known about the molecular mechanisms and animal models that are associated with the pathogenesis of AVSD.
摘要：
功能齐全的四腔心脏的发展在很大程度上取决于分隔心房和心室的结构的正确形成。该过程的干扰通常导致允许充氧和脱氧血液混合的缺陷。房室间隔缺损（AVSD）是一类先天性心脏畸形，其特征是存在原发性房间隔缺损（pASD）。常见房室瓣（cAVV），经常还有室间隔缺损（VSD）。尽管历史上认为AVSD是由于心内膜房室垫无法正常发育和融合所致，最近的研究已经确定,抑制房室间充质复合物其他成分的发育也可导致房室间隔缺损.背侧间充质突起（DMP）在AVSD发病机制中的作用已在使用AVSD动物模型的研究中得到充分证明。此外,初步数据表明，位于主房间隔前缘的间充质帽在某些情况下也可能涉及。在这一章中,我们综述了目前已知的与AVSD发病机制相关的分子机制和动物模型。
