Fig. 7. Ventricular septal defects in Cited2-null embryos. (A) Three-dimensional model of a 14.5 dpc Cited2-null heart, viewed from the ventral side. (B) Ventral aspect, after removal of the ventral and lateral walls of the ventricles, up to (but not including) the ventricular septum (VS). The ventral and lateral walls of the atrial chambers have also been removed. The right ventricle has only a small volume. (C,C') Model of (B) after 90° rotation (viewed from the left). A ventricular septal defect (VSD) is evident beneath the outflow tract, above the endocardardial cushion material (green, asterisk). A second VSD can be seen beneath the free margin of the septal leaflet (yellow) of the single atrioventricular valve. RA, right atrium; LA, left atrium; RV, right ventricle; LV, left ventricle.