231 



bicuspid or mitral, and the aortic or semilunar. It may consist of mere 

 inflammation and swelling, or the edges of the valves may become 

 agglutinated hj the organization of the exudation, thus narrowing the 

 passage. Valvular obstruction and adhesions may occur, or the tendi- 

 nous cords may be lengthened or shortened, thus obstructing the orifices 

 and permitting the regurgitation of blood. In protracted cases the 

 fibrous tissue of the valves may be transformed into tibro-cartilage or 

 bone, or there may be deposits of salts of lime beneath the serous mem- 

 brane, which may terminate in ulceration, rupture, or fissures. Some- 

 times the valves become covered by fibrinous, fleshy, or cartilaginous 

 vegetations or excrescences. In cases of considerable dilatation of the 

 heart there may be atrophy and shrinking of the valves. 



Symptoms. — Valvular disease may be indicated by a venous pulse, 

 jerking pulse, intermittent pulse, irregular pulse; palpitation; constant 

 abnormal fullness of the jugular veins ; difficulty of breathing when the 

 animal becomes excited, or is urged out of a walk or into a fast trot; 

 attacks of vertigo; congestion of the brain; dropsical swelling of the 

 limbs. A blowing, cooing, or bubbling murmur may sometimes be heard 

 by placing the ear over the heart on the left side of the chest. 



Hypertrophy, or dilatation, or both, usually follows valvular disease. 



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

 j)reparatiou8 of iron, gentian, and ginger may be given. When 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 endocarditis, the 

 iodide of potassa and general tonics, sometimes stimulants, when gen- 

 eral debility supervenes, may be of temporary benefit. Very few ani- 

 mals recover, or remain useful for any length of time, after once marked 

 organic changes have taken place in the valvular structure of the heart. 



ADVE?TTITIOUS GROWTHS IN THE HEART. 



Fibrous, cartilaginous., and hony formations have been observed in 

 some rare instances, in the muscular tissue. Isolated calcareous masses 

 have sometimes been imbedded in the cardiac walls. Fibrinous coagula 

 and polypous concretions may be found in the cavities of the heart. The 

 former consist of coagulated fibrin, separated from the mass of blood, of 

 a wliitifih or yellowish white color, translucent, of a jelly-like consistence, 

 and having a nucleus in the center. They may slightly adhere to the sur- 

 face of the cavity, from which they can easily be separated without 

 altering the structure of the endocardium. They probably result from 

 an excess of coagulability of fibrin, which is i)roduced by an organiza- 

 tion of the lymph during exudation. They are usually found in the 

 right auricle and ventricle. 



Polypous concretions are firmer than 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 



