CONGENITAL MALFORMATIONS AND DISPLACE- 

 MENTS OF THE HEART. 



Ectopia Cordis. Cyanosis, pervious foramen ovale. Symptoms : blue 

 mucosse, coldness, staring coat, unthriftiness, unequal to exertion, palpi- 

 tations, murmur before the first heart sound. Obstructed circulation in the 

 lungs as a cause of cyanosis, cyanosis as a cause of lung disease. 



These have been much less frequently observed in the lower 

 animals than in man. The anomalies observed in mammals in- 

 clude the following: The displacement of the heart to the right 

 side of the chest ; displacement entirely out of the chest (ectopia 

 cordis) ; permanent communication between the right and left 

 auricles (cyanosis) ; entire absence of heart ; two hearts ; one 

 common ventricle communicating withtwo auricles, as in reptiles ; 

 three ventricles ; only one auricle ; absence of one or several 

 valves ; absence of the pericardium ; variations in the mode of 

 connection of the heart and large vessels, etc. 



Displacements of the heart have been especially studied by 

 Hering on calves. The breast bone remained as originally devel- 

 oped in two lateral halves, and the heart remained outside con- 

 nected with the interior of the chest only by its large vessels. 

 The heart thus exposed and covered only by its investing mem- 

 brane (pericardium) afforded an excellent opportunity to study 

 its action, of which Hering freely availed himself. Animals 

 affected in this way survived their birth but a very short time. 

 An approach to this condition was forty years ago made familiar 

 to the medical world in the person of M. Gouz, a German me- 

 chanic, the movements of whose heart could be easily watched 

 through a fissure in the breast bone. 



Permanent communication between the two auricles. 

 Pervious foramen ovale. Cyanosis. Previous to birth there 

 is an opening between the right and left auricle, allowing the 

 blood to flow from the former into the latter in place of, as in after 

 life, descending into the right ventricle and thence circulating 

 through the lungs. At birth this is contracted, and in a few days 

 is completely closed in accordance with the new life, which de- 

 mands that all blood must circulate through the lungs in order to 

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