DISEASES OF THE HEART. 



447 



hypertrophy are so slowly developed that they may exist for years 

 without becoming apparent by serious general troubles. Hyper- 

 trophies which are of some gravity, such as those accompanying 

 chronic nephritis, are marked by a full pulse and a more intense 

 cardiac impulse than in a normal state, with loud and clear sounds, 

 and an increased extent of the precordial dulness. But this char- 

 acteristic symptomatic picture is rarely observed, for hypertrophy 

 through permaueut insufficiency soon makes way for a state of 

 dilatation, relaxation, of the heart, aud idiopathic hypertrophy is 

 exceedingly rare. 



Most of the cases designated in veterinary publications and in 

 practice under the name of cardiac hypertrophy are certainly only 

 complications of active and passive dilatations, and seen in this 

 latter affection only. The geueral symptoms of this double affection 

 are confounded with those of non-compensated valvular iusuffi- 

 ciency, and differ essentially from those of common cardiac hyper- 

 trophy. 



The increased extent of the precordial dulness is a symptom 

 common to both forms of the cardiac dilatation ; in the dog it may 

 be extended to the surface of the last false ribs. The relaxation 

 of the hypertrophied heart is marked at first by dyspnœa, palpita- 

 tions, an abnormal pulse, cerebral hyperemia, and anemia, vertig- 

 inous attacks (dog), extended circulatory troubles and their conse- 

 quences. The attention is generally attracted by the strength of 

 the cardiac impulse, which is palpitating, and perceptible on both 

 sides of the body ; this is sometimes shaken at each beating, phe- 

 nomena which are to be recognized at a distance ; but in some cases- 

 the impulse is imperceptible ; the heart sounds are irregular, roll- 

 ing, or alternating; the first is strong, metallic, vibrating; the 

 second is very weak or completely obliterated.^ The force of the 



1 The more or less distinct doubling of the heart bruits is relatively common in the 

 horse. It is most often observed at the first bruit (anapestic bruit — two short and one 

 long), sometimes at the second (galop hi^uit, dactylic bruit, one long and two short) 

 In most cases it does not seem to have the serious prognostic signification which iS' 

 attributed to it in man. It is generally explained by hypertrophy of the left ven- 

 tricle and the unequal rapidity of function of the tricuspid and mitral valves (non- 

 doubling of the first bruit) or aortic or pulmonary sigmoids (non-doubling of the 

 second bruit). Perhaps, in the horse, it is the expression of a cardiac trouble pro- 

 duced by excessive and repeated exertions to which most draught animals are subject. 

 Whatever the cause may be, it is an established fact that we may observe it upon 

 horses used every day in the hardest kind of service without showing any serioua, 

 respiratory or circulatory troubles. — n. d. t. 



