DISEASES OF THE HEART, BLOOD VESSELS, AND LYMPHATICS. 81 



In extreme cases tapping the pericardium with a trocar and can- 

 nula to draw off the fluid is resorted to, but the operation requires 

 exact anatomical knowledge. 



After death from pericarditis there is always more or less fluid 

 found in the pericardium ; the surfaces are rough and covered with a 

 j^ellow-colored exudate. There are also in many cases adhesions to 

 a greater or less extent between the heart and pericardium. 



MYOCARDITIS. 



Inflammation of the muscular structure of the heart occurs in 

 limited, circumscribed areas, as evidenced by post-mortem examina- 

 tion, and it is probably always somewhat involved in connection with 

 pericarditis and endocarditis. It may readily be inferred that if the 

 whole organ were inflamed death would ensue immediately. Usually 

 myocarditis results from the preexistence of blood poisoning or of 

 some infectious febrile disease. 



Symptoms. — The chief symptoms are those of heart weakness. 

 The heart beat is fast, weak, and often irregular. Kespiration is 

 difficult and rapid. There is great general wealmess and depression. 

 Death comes suddenly. 



Treatmejnt. — Treatment consists in supporting the animal by the 

 use of stimulants, such as ammonia, coffee, digitalis, camphor, etc. 

 Complete quiet must be provided, and the general care should be as 

 in pericarditis. 



ENDOCARDITIS. 



When the membrane which lines the cavities of the heart — ^the 

 endocardium — suffers inflammation, the disease is called endocarditis. 

 The cause is another disease, during which substances that irritate 

 the lining of the heart are produced and admitted into the circula- 

 tion. These substances are usually living organisms, or it is possible 

 that in some cases they are chemical irritants. Endocarditis occurs 

 as a complication of or sequel to pneumonia, blood poisoning, inflam- 

 mation of the womb, rheumatism, or severe wounds or abscesses. 

 The symptoms are much the same as those of pericarditis, and it is 

 difficult to discriminate between the two affections. There is a 

 jugular pulse, the legs may become dropsical, and there is a tendency 

 to faint if the head is elevated suddenly. The bellowslike sound 

 is more distinct than it is in pericarditis. It is the most fatal of 

 heart diseases, because of the liability of the formation of clots, 

 which may adhere to the valves, change in the structure of the valves, 

 and often a complication with an abnormal condition of the blood. 

 .54793°— 23 6 



