194 MANUAL OF EQUINE MEDICINE. 



in consequence of the increase of work thus thrown 

 upon it. 



After a time the hypertrophy giveaway to dilatation, owing 

 to impaired nutrition and degeneration of the cardiac walls, 

 arising from imperfect filling of the coronary arteries during 

 the ventricular systole. 



Implication of the mitral valve follows after a while, 

 and the symptoms of mitral regurgitation are manifested. 



The pulse in aortic regurgitation is sudden and jerky, and 

 is termed the ' water-hammer pulse,' or * Corrigan's pulse.' 



In aortic obstruction the pulse is not materially altered. 



TREATMENT OF CHRONIC VALVULAR DISEASES. 

 — The treatment of the valvular diseases can only be pallia- 

 tive, and in most instances it is not an object to prolong life 

 in horses incapable of exertion. Kegulation of work, which 

 should not be in excess of the powers of the animal, and good 

 diet, are the first essentials in the treatment of cardiac diseases. 



Tonics, such as iron, nux vomica, and other vegetable tonics, 

 are indicated in most cases, but we must,^^ in all cases, treat 

 the symptoms as they arise. When there is great irritability 

 of the heart, belladonna, bromide of potassium, and chloric 

 ether are of service in alleviating the distressing symptoms. 

 Digitalis is of great efiicacy as a heart tonic, and is indicated 

 whenever cardiac failure is threatening. 



DEGENERATIVE CHANGES OF THE HEART. 



FATTY DEGENERATION OF THE HEART.— Under 



the term fatty degeneration are included two diff'erent patho- 

 logical conditions. These are fatty metamorphosis, or 

 degeneration proper, in which the fat is derived from the 

 metamorphosis of the cardiac muscle, and fatty degeneration, 

 where it is derived from the oleaginous, saccharine, or nitro- 

 genous principles of the food. 



