DISEASES OF THE CIRCULATORY SYSTEM. 187 



Clonic spasms of the superficial muscles of the anterior 

 part of the body are present in many cases of endo- 

 carditis. 



Owing to the uncertain character of the symptoms, endo- 

 carditis is not easily diagnosed from pericarditis. 



Sequelae. — Inflammation of the endocardium is usually 

 followed by structural changes of the valves, and this change 

 induces dilatation and alteration in the cavities of the heart. 

 Weakened cardiac action and dropsical effusions may follow 

 in various parts of the body. 



Morbid Anatomy — The endocardium consists of a layer 

 of connective-tissue with an endothelial lining. The in- 

 flammation is more marked round the orifices and in connec- 

 tion with the valves and their appendages, and, in rheu- 

 matism, particularly in the valves. During the inflammatory 

 process the deeper layers of the endothelium become rapidly 

 infiltrated with young cells, and the inter-cellular substance 

 becomes softened and destroyed, and thus there is formed a 

 soft tissue composed entirely of cells. This new tissue 

 projects through the endothelium in the form of minute 

 granulations and vegetations upon the surface of the softened 

 valve. There is also more or less increase of vascularity in 

 the external endothelial layers; but the above changes 

 occur in an almost non- vascular tissue. 



The roughened granulations act as foreign bodies, and 

 thus frequently induce coagulation or deposition of fibrin 

 upon themselves. 



The cell infiltration may break down, and form an endo- 

 thelial ulcer or a small abscess. The inflammatory process 

 is generally, however, less intense and malignant. The 

 granular valves may then adhere to each other or to an 

 inflamed patch in the wall. The new cell growths become 

 organized into a fibrin ated structure, whilst in part it 

 undergoes fatty and calcareous degeneration. 



