CARDITIS. MYOCARDITIS. 



Definition. Rare. Complicates pericarditis and endocarditis, wounds of 

 the heart, and tubercular and other deposits, Symptoms. Treatment. 



Definition. Inflammation of the muscular substance of the 

 heart. 



This is a comparatively rar6 affection and is necessarily limited 

 to a small portion of the heaTt's substance, otherwise, the cardiac 

 contractions must cease in obedience to the general law that the 

 normal function of an inflamed organ is for the time abolished. 

 It is mainly seen as a concomitant of endocarditis or pericarditis, 

 and extends only to the superficial muscular layers ; or it results 

 from a wound as in the penetration of the heart by a needle or 

 other sharp-pointed body and is then equally circumscribed. It 

 has been seen as a complication in infectious diseases — aphthous 

 fever, influenza, infectious bronchitis, strangles, pysemia, sep- 

 ticaemia, pneumonia, in cows parturient metritis and tuberculosis, 

 in dogs distemper. 



The evidences of the existence of carditis are chiefly the lesions 

 met with after death, ist, The existence of abscesses in the 

 heart's substance associated with polypus (Gowing, I,eblanc, 

 etc.,) or otherwise (Reynal). Also diffuse suppuration in the 

 heart's substance (Puze, etc. ) 2nd, Softening of the muscular 

 substance, a state occasionally met with when an animal has died 

 of ruptured heart. This is shown in spots and patches of a 

 yellowish red or grayish red color, soft and friable, fibrillation 

 largely effaced, but with cloudy swelling and cell infiltration. 

 It may however be mainly a degeneration into fatty granules. 

 3d, Ulceration of the walls of the heart as reported by Mercier 

 in a case of endocarditis. 4th, Transformation, and induration 

 of the heart's substance whether into fibrous tissue, cartilage or 

 bone. This last condition of the walls of the right auricle and 

 ventricle has been repeatedly seen in old horses, the change 

 being in certain cases so extensive that one is left in wonder as 

 to how circulation could have been carried on. Three specimens 

 of this kind were preserved in the museum of the Alfort 

 Veterinary College, Paris, and the Royal Veterinary College, 

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