476 DISEASES OF THE CIRCULATORY SYSTEM. 



dilated and little by little hypertrophied ; the discharge of the blood 

 into the pulmonary veins is obstructed, there is blood stagnation in 

 these vessels, in the capillaries and the arteries of the lungs, and 

 finally in the right heart, which in the end becomes atrophied. On 

 account of the increased blood pressure in the pulmonary artery the 

 second sound (pulmonary sound) is strengthened. When the right 

 heart can no longer withstand the circulatory troubles cyanosis 

 occurs, also dyspnœa, swelling of the jugular veins, venous pulse, 

 dropsies, etc.^ 



Characteristic symptoms of mitral insufficiency : Systolic blowing, 

 strong diastolic pulmonary sound, hypertrophy of the right heart, 

 weak pulse, dyspnœa, stagnation in the venous system. 



Schmidt^ has described an interesting case of mitral insufficiency 

 in the horse. Symptoms : pulse accelerated, small, arrhythmic ; 

 loud systolic bruit (wheezing) at the apex, increase of the precordial 

 dulness, œdema under the chest, etc. 



II. Contraction of the mitral orifice. This has as a 

 consequence obstruction to the entrance of blood into the left ven- 

 tricle at the time of the contraction of the auricle, and produces 

 a diastolic bruit (blowing). The incompletely filled ventricle has 

 a tendency to atrophy ; the pulse becomes small and weak. The 

 left auricle becomes dilated and hypertrophied ; the pulmonary 

 circulation is interfered with, from which results dilatation and 

 hypertrophy of the right heart ; the diastolic pulmonary sound is 

 very loud. 



Characteristic symptoms of mitral contraction. Diastolic blowing, 

 strong pulmonary sound, very small pulse, serious circulatory 

 troubles, and especiajly pulmonary obstruction. 



This lesion has been described in the horse and pig by Daudt, 

 Schneidemiihl, Appenrodt, and a few others. 



III. Tricuspid insufficiency. It permits the return of the 

 blood into the right auricle, and is indicated by a systolic bruit 

 (blowing). The flowing back of the blood into the auricle spreads 

 to the veins (venous pulse), and produces a stagnation in the whole 



the heart; it is weaker in the whole height of the posterior half of this organ. It is 

 mild when the insufficiency is simple and coarse when vegetations are present. — l. t. 



1 Chronic alterations of the mitral which are evident enough to produce insuf- 

 ficiency, may exceptionally be found at the autopsy of horses not showing any serious 

 respiratory or circulatory trouble during their life. We have obtained a remarkable 

 example of it. — n. d. t. 



2 Schmidt: Preuss. Mittheil., 1877-78. 



