Figure 4-34. Embryology of the atrioventricular junction. The primitive atrioventricular canal is partitioned by the growth of the endocardial cushions (EC), interatrial septum (IAS), and interventricular septum (IVS).

• 房室交界处的胚胎发育。原始房室管生长分化为心内膜垫（EC），房间隔（IAS）和室间隔（IVS）。