RUPTURE OF THE PERICARDIUM. 



This is reported as a rare occurrence in horse, ox, and dog, but 

 the cause in each case has only been conjectured as being a violent 

 blow or shock operating on an already diseased and weakened 

 pericardium. Cuthbert records a case in the horse in which the 

 pericardium was lacerated for a distance of eight inches from 

 the apex so as to allow the protrusion of a large part of the 

 heart. The margins of the laceration were inflamed and thick- 

 ened. Eeather publishes a case in which a horse, during work, 

 sustained a laceration of over two inches long. Larcher notes 

 cases of rupture of the root of the aorta, implicating the peri- 

 cardium, so that a mass of blood escaped into its cavity. In 

 cattle, the perforation of the pericardium is commonly due to 

 foreign bodies migrating from the reticulum. Cases of the kind 

 are further charged on perforation by parasites, and vulnerant 

 bodies entering from without. In both cattle and dogs the pres- 

 ence of tubercles on the pericardium impairs its tenacity and is a 

 frequent cause of perforation. Penetrating wounds are more 

 common in these animals than in horses. Rupture has occurred 

 in septic effusion into the pericardium with the evolution of gas 

 in the cavity. A congenital aperture in the pericardium of a 

 puppy is noted by Paul Bert. 



The result of the rupture is shown in sudden and usually 

 urgent phenomena of cardiac disorder and weakness, violent pal- 

 pitation being associated with an unequal, intermittent, weak 

 pulse gradually becoming imperceptible. Death usually by syn- 

 cope occurs, speedily or after an interval of from one to fourteen 

 days. The lesion is always hopeless. 



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