324 DISEASES OF THE CIRCULATORY SYSTEM. 



sclerosis and fibroid change in the kidneys and other organs. 

 As a result, the heart may be hypertrophied by the increased 

 work imposed upon it, but much more frequently the muscle- 

 fibres are atrophied by the mechanical pressure of the newly 

 formed fibrous tissue, and are found to have undergone 

 granular and fatty degeneration. Circumscribed areas of 

 fibroid substitution are often consecutive to degenerative 

 changes produced by obstruction of the coronary arteries. A 

 saccular dilatation aneurism may result from the thinned 

 heart-wall giving way to pressure from within at such a 

 point. 



Endocarditis. 



Inflammation of the endocardium usually aifects the valves ; 

 when affecting the cavities of the heart it may be designated 

 specially as mural endocarditis. 



Acute endocarditis is rarely a primary affection. The most 

 frequent cause is acute articular rheumatism. It occurs also 



FIG. 143. 



FIG. 144. 



Inflammation of aortic valves, the ear- 

 lier stage of the process, showing the 

 situation of the inflammatory gran- 

 ulations (Green). 



Inflammation of mitral valve, the ear- 

 lier stage of the process. Valve seen 

 from the auricular surface, showing 

 the situation of the inflammatory 

 granulations (Green). 



in the course of pneumonia, puerperal septicaemia, scarlet fever, 

 typhoid fever, gonorrhoea, and, in fact, in any acute infectious 

 disease. It occurs also in Bright's disease, cancer, and diabetes. 

 The most characteristic lesions are the so-called warty 

 vegetations formed along the line of contact of the valves, 

 especially on the auricular aspect of the mitral, and in a row 



