258 DISEASES OF THE HORSE. 



fast trot ; attacks of vertigo ; congestion of the brain ; dropsical swell- 

 ing of the limbs. A blowing, cooing, or bubbling murmur may some- 

 times be heard by placing the ear over the heart on the left side of 

 the chest. 



Hypertrophy, or dilatation, or both, usually follow valvular 

 disease. 



Treatment. — When the pulse is irregular or irritable, tonics, such 

 as preparations of iron, gentian, and ginger, may be given. AVlien 

 the action of the heart is jerking or violent, 20 to 30 drop doses of 

 tincture of digitalis or of veratrum viride may be given until these 

 symptoms abate. As the disease nearly always is the result of endo- 

 carditis, the iodid of potassium and general tonics, sometimes stimu- 

 lants, when general debility supervenes, may be of temporary benefit. 

 Very few animals recover or remain useful for any length of time 

 after once marked organic changes have taken place in the valvular 

 structure of the heart. 



ADVENTrriOUS GROWTHS IN THE HEART. 



Fibrous, cartilaginous, and bony formations have been observed in 

 some rare instances in the muscular tissue. Isolated calcareous 

 masses have sometimes been embedded in the cardiac walls. 

 Fibrinous coagula and polypous concretions may be found in the 

 cavities of the heart. The former consist of coagulated fibrin, sepa- 

 rated from the mass of blood, of a whitish or yellowish white color, 

 translucent, of a jellylike consistence, and having a nucleus in the 

 center. They may slightly adhere to the surface of the cavity, from 

 which they can easily be separated without altering the structure 

 of the endocardium. They probably result from an excess of coagu- 

 lability of fibrin, which is produced by an organization of the lymph 

 during exudation. They are usually found in the right auricle and 

 ventricle. 



Polypous^ concretions are firmer than in the preceding, more 

 opaque, of a fibrous texture, and may be composed of successive 

 layers. In some instances they are exceedingly minute, while in 

 others they almost fill one or more of the cavities. Their color is 

 usually white, but occasionally red from the presence of blood. They 

 firmly adhere to the endocardium, and when detached from it give it 

 ? torn appearance. Occasionally, a vascular communication seems 

 to exist between them and the substance of the heart. They may 

 be the residt of fibrinous exudation from inflanmiation of the inner 

 surface of the heart or the coagulation of a portion of the blood 

 which afterwards contracts adhesion with the heart. These con- 

 cretions prove a source of great inconvenience and often danger, no 

 matter how formed. They cause a diminution in the cavity in 

 which they are found, thus narrowing the orifice through which the 



