VALVVLAB DEFECTS. 145 



tolic bruit (this is absent in some cases) ; considerable increase of 

 the second (pulmonic) bruit; very small, irregular pulse; great 

 difficulty in respiration ; and dropsy makes its appearance early in 

 the disease. 



Disease of the Aortic Valves. This condition of the semilunar 

 valves causes a dilatation and hypertrophy of the left ventricle 

 and flattening of the papillary muscles. 



The clinical symptoms are as follows : A very strong heart-beat; 

 increase of the heart-dulness on the left side; a full, bounding 

 pulse is very frequently noticed. This character of the pulse is 

 also noticed in small arteries that in normal conditions have no 

 distinct pulse. Shortness of breath, oedema, and dropsy of the 

 dependent parts. 



Stenosis of the Aortic Openinff. Rare in the dog. 



The clinical symptoms are a systolic bruit, a very slight sound 

 of the aorta, small, weak pulse, general ansemia, etc. 



Imperfect action and disease of the tricuspid valves cause dis- 

 tention of the right auricle, and it also has a systolic murmur on 

 the right side and a strong, venous pulse. Stenosis of the right 

 venous opening and defects of the pulmonary valves are extremely 

 rare. 



We very frequently have a combination of a contraction of an 

 • opening and also a deposit on or retraction of the valve at that 

 opening and also a single valvular defect, and the two make a 

 combination of symptoms that are rather hard to separate. 



Prognosis and Therapeutics of Valvui,ar Defects op 

 THE Heart. A diseased valve must be considered incurable, 

 but it may exist for a long time without causing any decided dis- 

 turbance of the general circulation. It is impossible to predict 

 how long a "compensating" state will continue. Mitral defects 

 seem to last the longest. This conclusion is arrived at from the 

 fact that it is quite common to hold post mortems on dogs that have 

 been apparently healthy during life and find serious heart-defects. 



Compensating heart-defects do not require any treatment. We 

 try to aid the heart in its efforts by giving nutritive diet and re- 

 moving all exciting causes, such as great or prolonged exertion. 



As soon as the heart begins to weaken and the difficulty in res- 

 piration increases, accompanied by oedema, palpitation, etc., we 

 must use heart-tonics — digitalis, strophanthus, caffeine, etc. 



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