胚胎发育时,如果静脉窦向上弯曲进入围心腔发育异常,静脉窦未能完全进入围心腔,使部分静脉窦在围心腔之外,导致静脉窦在围心腔内短缺和/或发育不全。短缺时,可造成心包腔内无下腔静脉;短缺和/或发育不全时,不仅造成心包腔内无下腔静脉而且会造成心血管发育畸形,如静脉窦型房缺,下腔型房缺等。我们在临床工作中遇见二例,一例伴有“下腔型”房缺,另一例伴有空间隔缺损。现将两病例简介如下。 During embryonic development, if the sinus is bent upward into the pericardial cavity, the venous sinus fails to fully enter the pericardial cavity, causing part of the sinus to be outside the pericardial cavity, resulting in a shortage and / or development of the sinus in the pericardial cavity Incomplete. Shortage, can cause pericardial cavity without inferior vena cava; shortage and / or hypoplasia, not only caused by the pericardial cavity without vena cava and can cause cardiovascular deformities, such as venous sinus atrial septal, inferior ventricular atrial septal defect Wait. We met two cases in clinical work, one with “inferior chamber” atrial septal defect, the other with congenital septal defect. Now two cases are as follows.