CONGENITAL HEART DISEASE. 



Superior vena cava. 

 Undefended space. 



Fossa ova Us. 



Eustachian valve. 

 Inferior vena cava. 



Aorta. 



Cavity of right 

 ventricle. 



Tricuspid valve. 



FIG. 28. Diagram of right cavities of the heart to show possible 

 sites of obstruction at each end of the infundibulum of the right 

 ventricle. Obstruction at A gives rise to a heart with three 

 ventricles. Obstruction at B is in the position of the pulmonary 

 valve. Obstruction at C involves the stem of the pulmonary 

 artery. 



Superior vena cava. 



Aorta 



Dilated right auricle. .. 



Pulmonary valve with 

 only two cusps. 



Separated 



infumlibulum form- 

 ing a third ventricle. 



Tricuspid valve. .. - '" 



Hypertrophied right 

 ventricle. 



Obliterated ductus- 

 arteriosus. 



.Pulmonary artery. 



Left auricle. 

 Aortic valves. 



Aortic septum. 



Defect in 

 ventricular septum.. 



' ' - Left ventricle. 



Septum inferius. 



FIG. 29. Heart with three ventricles, from a man aged 19 years. 

 Semi-diagrammatic. (St. Thomas's Hospital Museum.) 



[To face page 258. 



