DISEASES OF THE HOESE. 235 



iodide of iron and gentian to support the strengtli will be indicated, 

 but the iodide of potassa, in 1 or 2 dram doses, two or three times a 

 day, must not be abandoned so long as there is an evidence of effusion 

 or plastic exudate accumulating in the pericardial sac. Where the 

 effusion is great and threatens the life of the patient, tapping b}- an 

 expert veterinarian ma}^ save the animal. 



VALVULAR DISEASE OF THE HEART. 



Acute valvular disease can not be distinguished from endocarditis, 

 and chronic valvular affections are generally the result of endocardial 

 inflammation. The valves of the left side are the most subject — the 

 bicuspid or mitral and the aortic or semilunar. The derangement 

 may consist of mere inflammation and swelling, or the edges of the 

 valves may become covered by the organization of the exudation, thus 

 narrowing the passage. Valvular obstruction and adhesions may 

 occur or the tendinous cords ma}^ 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 fibro-cartilage or bone, or there may be deposits of salts of lime 

 beneath the serous membrane, which may terminate in ulceration, rup- 

 ture, or fissures. Sometimes the valves become covered b}^ fibrinous, 

 fleshy, or hard vegetations, or excrescences. In cases of considerable 

 dilatation of the heart there may be atrophy and shrinking of the 

 valves. 



Si/mj)to)ns. — Valvular disease may be indicated by a venous pulse, 

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

 abnormal fullness of the jugular veins; difiiculty 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 \nsi\ sometimes 

 be heard \>y placing the ear over the heart on the left side of the chest. 



Hj^pcrtrophy, 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. 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 nearlj^ alwa3's is the result of endo- 

 carditis, the iodide of potassa and general tonics, sometimes sthnu- 

 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. 



ADVENTITIOUS GROWTHS IN THE HEART. 



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

 some rare instances in the muscular tissue. Isolated calcareous masses 



