DISEASES OF THE HEART 465 



Many years ago Youatt referred to the common presence of these 

 vegetations in the heart of the pig, and he noticed in particular that the 

 animals in which the disease was detected in the slaughter-houses had 

 given no evidence whatever of the existence of such tumours during life. 



Valvular disease in the heart of the horse is, according to Professor 

 Nocard, more common than it is suspected to be. He has given a table 

 of the relative frequency of the different valvular affections in that animal. 

 Of forty-two subjects it was found that thirty-eight had disease of the 

 valves of the aorta. In the other four, disease both of the aortic and 

 mitral valves was detected. In some cases one of the normal sounds is 

 obliterated, or may be reduplicated, or it appears every other or every 

 second beat. 



The character of the morbid alteration varied considerably. In some 

 cases the valves were merely thickened and hardened, in others they were 

 contracted, sometimes they were indented or perforated, and in others they 

 were covered with fibrinous deposits. 



In the cases referred to, the diagnosis had been made during the life of 

 the animal, and in almost all of them a blowing noise, which occurred 

 during what would ordinarily be the interval between the normal sounds, 

 was detected by auscultation. It is remarked by Dr. W. L. Zuill, in his 

 translation of the work on pathology by Drs. Freidberger and Frohner, that 

 the first symptoms of this chronic inflammation of the lining membrane of 

 the heart is the marked weakness of the animals while at work. They will 

 stop, refusing to advance, and do not respond to the voice or to the whip. 



Treatment is not likely to be attended with any great advantage. 

 The recommendation to avoid excitement and any active exertion is 

 tantamount to proposing to keep the affected horse in the condition of 

 useless idleness. 



For the purpose of temporary alleviation of the most marked symptoms, 

 the use of iodide of potassium with digitalis is recommended, but, excepting 

 where some special value is placed on the patient, economy, and humanity 

 too, would be best considei'ed by having him destroyed. 



HYPERTROPHY— ENLARGEMENT OF THE HEART 



The different forms of disease and deformity affecting the valves, which 

 have been adverted to in the preceding remarks, necessarily cause obstruc- 

 tion to the circulation, attended with regurgitation of the blood and increase 

 of pressure in some of the cavities of the heart. Any obstruction arising 

 out of disease of the valves is likely to occasion enlargement of the heart in 

 one or another part of the organ according to the particular valves affected. 



