Rupture of the Heart. 1077 



influence of a normal blood pressure, but in most cases exciting 

 causes may be demonstrated, such as severe exertion, straining 

 on defecation, bloating, excitement during mating, during an 

 operation, etc. As these exciting causes become active much 

 more frequently in horses, heart rupture is observed more 

 frequently in the horse than in other animals, with the excep- 

 tion of traumatic rupture of the heart in cattle. 



Anatomical Changes. The pericardium contains more or 

 less fresh blood (hemopericardium). A solution of continuity 

 in the fibers of the heart muscle is often found in the walls 

 of the ventricles, less often in the walls of the auricles. The 

 tear is almost always small, its borders ragged and its path 

 through the ventricular wall usually corresponds to a zigzag 

 line, so that it is only with difficulty possible to introduce a 

 probe into the ventricle. Sometimes the tear takes place in 

 the interventricular septum (Dieckerhoff), and in such cases 

 hemorrhage does not take place into the pericardium. 



Symptoms. In general only symptoms of cardiac paralysis 

 or of internal hemorrhage are evident, and these cause death 

 rapidly because the heart is compressed by the blood or hindered 

 in its diastolic dilatation, or then the action of shock upon the 

 lieart becomes manifest. The occurrence of a rupture is usually 

 announced by sudden signs of indisposition. In a part of the 

 cases death occurs suddenly, at night, or so rapidly that hardly 

 any symptoms are ascertained aside from collapse and con- 

 vulsions. 



Treatment. A rupture of the heart which has actually 

 occurred cannot be treated. Its appearance, however, may 

 sometimes be prevented by removing the exciting causes. 



Literature. Berndt, A. f. Tk., 1893. XIX. 314. — Graux, J. vet., 1905. 

 231 _ Maleval, Eec, 1904. 508. — Petit, Bull., 1905. 166. — Piot-Bey, Bull., 

 1906. 425, 430. — Vogel, B. t. W., 1906. 682. 



9. New-Formation in the Heart. Neoplasmata Cordis. 



New-formations which occur in the wall of the heart are of only 

 slight interest, not only on account of their rarity, but also because their 

 presence in the heart of living animals can rarely ever be ascertained 

 with even a small degree of probability. According to the communica- 

 tions to literature, fibroma, fibromyxoma, myxoma, lipoma, sarcoma (in 

 horses melanosarcoma) and fibrosarcoma, metastatic adenoma, carci- 

 noma, exceptionally also lymphosarcoma, angioma, lymphangioma occur 

 preferably in the ventricular wall and may, with the exception of 

 carcinoma or sarcoma, be primary. The most frequent growths are fibro- 

 sarcoma, and in horses melanosarcoma. The new- formations which pro- 

 ject towards the heart cavities or towards the pericardial cavity are 

 not infrequently pediculated. 



