230 



of certainty that we Avill liave to confine ourselves to a general out- 

 line, giving attention to such symptoms as may serve to lead to a 

 knowledge of their existence, with directions for treatment, care, etc. 



Nervous affections often i^roduce prominent heart sj'mptoms by 

 causing functional disturbance of that organ, Avhich, if removed, will 

 leave the heart restored to perfect vigor and normal action. Organic 

 changes involving the heart or valves, however, usually grow worse 

 and eventually prove fatal. Therefore it is necessary that we arriA-e 

 at an appreciation of the true nature and causes, so that we may 

 be able to form a true estimate of the possibilities for recovery or 

 encouragement for medical treatment. 



Disease of the heart may occur at any age, but it is Avitnessed most 

 frequently in young horses, which, when being trained for fast work, 

 are often subjected to excessiA^e hardship and fatigue. NerA'ous or 

 timid animals also suffer from such diseases more frequently than 

 those of a sluggish disposition. Anj^ cause Avliich induces a Aiolent 

 or sudden change in the circulation may result in injury to the heart. 

 Sj-mptoms Avhich may frequently denote disease of the heart are dif- 

 ficult breathing or short-windedness, dropsies of the limbs, habitual 

 coldness of the extremities, giddiness or fainting attacks, inability to 

 stand Avork althougli tlie general appearance Avould indicate strength 

 and ability, etc. 



INFLAMMATORY DISEASES OF THE HEART. 



This Avill embrace myocarditis, endocarditis, and pericarditis. 



MYOCARDITIS — INFLAMMATION OF THE MUSCULAR STRUCTURE OF THE HEART. 



This is of rare occurrence Avithout imi)lication of the endocardium 

 or pericardium. That inflammation of the muscular Avails of the heart 

 may frequently exist to some slight degree, induced by excessive action, 

 can not be doubted. Post-moriem examinations occasionally reveal 

 abscess and degeneration within the Avails of this organ, Avhich were 

 not suspected during life. Myocarditis primarily involves the inter- 

 stitial muscular tissue and the blood vessels, and presents itself in a 

 sub-acute or chronic type, AAdiich often leads to induration or hyper- 

 trophy, occasionally to the formation of pus and abscess. It may also 

 lead to a dilatation of the heart and rupture. 



Causes. — Over-exertion or heart strain, influenza, rheumatism, pyae- 

 mia, extension of endocarditis or pericarditis, etc. Myocarditis usu- 

 ally involves the endocardial membrane very early in the attack, and 

 develops all the symptoms of endocarditis. Hence Ave Avill con- 

 sider, as most distinctive of inflammation of the heart, endocarditis. 



ENDOCARDITIS— INFLAMMATION OF THE LINING BIEMBRANE OF THE HEART, USUALLY 

 INVOLA^NG THE MUSCULAR STRUCTURE, 



It is frequently found in gcnei-al rheumatism, iuA^olving the serous 

 membrane, some of the specific or zymotic fevers, septic poisoning, etc. 



