Endocarditis. 333 



generating into calcareous matter, necrotic debris, or pus, several 

 instances of which as occurring in horse and cow are on record. 



These cases illustrate endocarditis by irifection {mycotic, via- 

 lignant, or idcerative endocarditis^ , which occurs independently, 

 or as an extension of a bacteridian disease, primarily localized 

 elsewhere in the system. Thus it is a secondary lesion in infec- 

 tious omphalitis, pneumonia, pleurisy, arthritis, abscess, pyaemia, 

 etc. Beside the general lesions of endocarditis and a great ten- 

 dency to molecular death of the new formations and the under- 

 lying tissues, there is the presence of specific germs which have 

 been the occasion of the disease. Among these the staphylococ- 

 cus pyogenes aureus, the streptococcus pyogenes, and the diplo- 

 coccus pneumoniae, have been particularly noted. In case the 

 valves were already diseased, they become especially liable to be 

 colonized b}' any such bacteria that may be circulating in the 

 blood. 



In the early stage there may be a mere swelling of the valves, 

 with as yet a smooth, unbroken surface, but with enlargement 

 and increase of the connective tissue cells, later fungous vegeta- 

 tions start out from the surface, and on these the fibrine of the 

 blood is deposited in layers. 



Besides the formation of clots on their surfaces other changes 

 occur on the cardiac valves as the result of inflammation. The 

 organization of the exuded lymph within and upon them leads to 

 rigidity, loss of elasticity, unevenness of their surface, contrac- 

 tion and puckering so that the}^ can no longer approximate to 

 each other, but leave the orifice imperfectly closed. They may, 

 moreover, have gristle or bone deposited in their substance. The 

 osseous degeneration of such new products appears to be the most 

 common cause of those ossifications of the heart, of which speci- 

 mens are to be found in nearly all veterinary museums. 



Chronic valve disease is thus found to be a common result of 

 endocarditis, and from the obstacle presented to the flow of blood 

 through the different cardiac orifices by the rigid, inelastic and 

 distorted valves, hypertrophy of the heart frequently supervenes. 



In our domestic quadrupeds ante-mortem clots and fibrinous 

 polypi have been chiefly formed in the right side of the heart, 

 and di.seased valves in the left. 



Symptojns. The general symptoms agree in many respects 



