188 MANUAL OF EQUINE MEDICINE. 



These changes produce permanent thickening, rigidity, 

 and shrinking of the valves, and consequent insufficiency 

 or stenosis, or both. 



The new tissue may continue to grow after the process 

 has subsided, and thus are produced vegetation and 

 papillary excrescences on the valve. These consist of a 

 lowly organized tissue, which tends to undergo fatty and 

 calcareous changes. 



Treatment. — The treatment resolves itself chiefly into 

 the treatment of the diseases with which the endocarditis is 

 associated. 



Cardiac sedatives are indicated when the irritability and 

 pain are great, but must be given with care. Bleeding is 

 recommended by some; but as it probably only gives 

 temporary relief, and probably favours coagulation and the 

 deposition of the fibrin on the roughened surfaces, it is best 

 not to adopt this measure. 



In cases where debility and exhaustion follow, stimulants 

 in moderate doses are necessary, 



MYOCARDITIS.— The muscular substance of the heart 

 may be the seat of inflammation, whereby it becomes 

 softened or, more rarely, indurated. Intense and concen- 

 trated inflammations, leading to the formation of abscess, 

 may occur as the result of a pysemic process. Myocarditis 

 rarely occurs except in connection with disease of the 

 endocardium and pericardium, whence the inflammation 

 spreads to the muscular tissue itself. It is an occasional 

 sequel of various acute fevers, and of pysemia and other 

 septic conditions of the blood. 



It gives no distinctive symptoms during life by which it 

 may be recognised, but the heart's action is weak and 

 irregular. 



