CONGENITAL HEART DISEASE. 



Right auricle. 



Infiindibulum of right 

 ventricle. 



Tricuspid orifice. 



Lower end of aortic 

 septum. 



Defect in ventricular 



septum. 



Cavity of hypertrophied 

 right ventricle. 



Septum inferius. 



Cavity of rudimentary 

 left ventricle. 



Aorta. 



Aortic isthmus. 



Ductus arteriosus. 

 Pulmonary artery. 



Left auricle. 



Depression indicating 

 position mitral orifice 

 should occupy. 



FIG. 35. Mitral atresia, rudimentary left ventricle. Defect in 

 upper part of the ventricular septum, and patent foramen ovale. 

 Patent ductus arteriosus. Descending thoracic aorta supplied 

 partly by aortic isthmus and partly by ductus arteriosus. Semi- 

 diagrammatic. 



Superior vena cava. 



Aorta. - 



Patent foramen ovale. 

 Right auricle. 



Position of obliterated 

 tricuspid orifice. 



Common ventricle. 



- - Left auricle. 



Pulmonary artery. 



_ . Mitral orifice. 



Pulmonary cusps, fused, 

 dug two small orifices. 



Aortic septum. 



FIG. 36. The heart of a " young person " with complete atresia of 

 the tricuspid orifice. The aorta and pulmonary artery are trans- 

 posed both laterally and antero-posteriorly. The pulmonary 

 artery is stenosed at the site of its valves and the septum 

 inferius of the ventricles is wanting. The course of the circula- 

 tion is indicated by the dotted arrows. Semi-diagrammatic. 

 (St. Thomas's Hospital Museum.) 



[To face page 264. 



