IG 8 DISEASES OF THE DOMESTIC ANIMALS 



and intermittent. Dilatation is also shown by the heart's impulse 

 being seen and felt over a large area, by the sounds becoming short 

 and weak and the action irregular and intermittent with the ex- 

 istence of a weak, quick, irregular pulse. Palpitation, shortness and 

 difficulty of breathing (cardiac asthma) on exertion or movement, 

 the pulsations of the heart not corresponding with those of the art- 

 ery, dizziness, twitching, cyanosis, edema, and dropsy, are addi- 

 tional symptoms characteristic of cardiac dilatation. Heart mur- 

 murs may be present owing to dilatation and incompetency of the 

 valves or to complication with valvular disease. 



(c) Myocarditis, Acute and Chronic. — Under this title 

 are included many forms of degeneration of the heart muscle, 

 cloudy swelling, fatty, amyloid, calcareous and fibroid in nature. 

 Direct extension in endo- and pericarditis, or invasion of bacteria 

 in general infectious diseases, commonly give rise to the acute forms, 

 which may eventuate in the chronic. Disease of the coronary ar- 

 teries (arteriosclerosis), with obstruction to the cardiac circulation, 

 is another frequent source of chronic myocarditis. 



Symptoms. — These indicate failure of the heart muscle, as 

 feeble, rapid, irregular (sometimes infrequent) pulse, shortness of 

 breath and edema without valvular murmurs and with dilatation. 

 Palpitation may sometimes occur, also general weakness, trembling 

 attacks, and dizziness. Diagnosis is very difficult, except in heart 

 failure following infectious disease, as valvular murmurs may be 

 present, and, on the other hand, no symptoms occur until the animal 

 drops dead. 



Treatment. — The treatment of the various forms of chronic 

 heart disease enumerated is dependent upon the predominant signs 

 and symptoms. The symptoms of chronic valvular disease are due 

 to failure of hypertrophy and compensation, so that the treatment 

 of this disorder is identical with that of enlargement of the heart, 

 when dilatation prevails over hypertrophy. Simple hypertrophy, 

 with violent action of the heart, can be best subdued with tincture 



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