PALPITATIONS IN THE HORSE. 



465 



trouble of the myocardium, with weakness or insufficiency of the 

 heart ; they are nearly the same as in advanced hypertrophy. The 

 precordial impulse, which is strong, irregular, tumultuous, is felt 

 over a greater surface ; the eye and ear sometimes perceive it at 

 some distance. The pulse is weak, irregular, often hardly felt ; in 

 the horse we may count 80 to 120 pulsations and more per minute. 

 The respiration is accelerated and difficult. We observe also great 

 weakness, trembling, and spells of vertigo. The temperature is 

 more or less high according to the nature and causes of the disease. 

 When this lasts long, phenomena indicating the existence of an 

 obstacle to the return circulation become apparent. 



There are cases where inflammation of the myocardium develops 

 very rapidly : the patient may suddenly fall as if struck by a thun- 

 derbolt (aphthous fever, tuberculosis). Death happens suddenly 

 through rupture or paralysis of the heart. In acute or suppurating 

 parenchymatous myocarditis we frequently observe this course and 

 termination. 



Differential diagnosis. It is very hard to distinguish myocar- 

 ditis from several other cardiopathies, especially passive dilatation, 

 endocarditis and pericarditis ; at times, in reality, the symptoms of 

 these affections have nothing characteristic. As a general rule, we 

 may conclude the existence of myocarditis when, with serious symp- 

 toms of cardiac distress, we do not observe any indication of organic 

 alteration of the heart (murmurs, friction bruits, etc.). 



Treatment. The treatment of myocarditis must be that for 

 cardiac weakness. Excitements and exertions must be avoided, the 

 myocardium should be sustained by a substantial alimentation, 

 stimulants, digitalis, caffeine, strophanthus, and the administration 

 of antifebriles. The principal indication is to combat the primary 

 affection. Subacute myocarditis does not yield to any treatment. 



[The veterinary publications contain a few cases of ossifica- 

 tion of the auricles of the heart which have been observed only 

 in old horses. It is mostly located upon the right auricle ; at times 

 it is bilateral but irregularly developed, the left auricle being 

 always the least altered. Sometimes it hardly reaches the size of a 

 silver dollar, at other times it is located upon the whole ceiling of 

 the auricle (Barrier and Yeret, Nocard, etc.), exceptionally this is 

 entirely involved (Renault, Barthélémy). In a case related by 

 Chuchu {Bull. SoG. centr. Vet., 1884) the right auricle, which was 

 completely ossified, was five times its normal size and weighed 1800 



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