ENDOCARDITIS 77 



ditis may be distinguished: (a) Acute parenchymatous, 

 (b) chronic interstitial, and (c) purulent (heart abscess). 



(a) The acute parenchymatous form involves the muscle 

 fibers of the heart. Macroscopically, the heart appears often 

 striped or spotted (tiger heart), is of friable consistency 

 and lighter Color than normal. 



(6) The chronic interstitial myocarditis involves the inter- 

 muscular connective tissue which proliferates, leading in 

 many cases to a thinning from atrophy of the heart muscle 

 with occasional local distention of the cavities (heart 

 aneurysm). 



< (c) Abscess of the heart is usually seen in traumatic 

 myocarditis of cattle and in pyemia. The musculature 

 of the heart will contain a number of pea- to walnut-sized 

 abscesses, or in some cases small, multiple, miliary pus 

 centres. 



Symptoms. — Acute myocarditis begins suddenly with 

 symptoms of heart weakness (palpitation, very rapid 

 pulse,, dyspnea). Dea!th may be apoplectic, due to heart 

 paralysis. Clinically, it is extremely difficult to distinguish 

 between myocarditis and acute dilatation of the heart, or 

 the parenchymatous degenerations so common in febrile 

 disorders. During life myocarditis is usually not diagnos- 

 able in animals. From pericarditis and endocarditis it 

 may be distinguished by the absence of the characteristic 

 bruits of these conditions. 



Treatment. — Heart stimulants especially injections of oil of 

 camphor (Biij), or caffein (3j), or veratrin are recommended. 



ENDOCARDITIS. 



Definition. — An inflammation of the endocardium which 

 may be (a) acute or (b) chronic. 



Acute Endocarditis. — Acute endocarditis is usually of 



infectious or hematogenous origin. It may therefore be 



due to several different microorganisms. In animals it is 



, usually caused by the bacteria of septicemia and pyemia. 



The streptococci, staphylococci, and varieties of the colon 



' v bacillus, which have entered the blood in puerperal septicemia 



Digitized by Microsoft® 



