7b CLINICAL DIAGNOSTICS. 



(pulsus rcgularis). In the dog and. according to Cadeac, 

 frequently in mules and asses, the pulse is often irregular and 

 intermittent. 



Fig, 23. 



Normal Pulse— Horse. 

 Marey's Sphygmograph — Art. trans, faciei. 



The rhythm of the irrc'^^ular and of the intermittent pulse 

 is abnormal, i. e., arhyihuiic. 



When the pulse is irregular tlie intervals between the 

 individual pulse beats are of unequal duration. 



This is due to lack of innervation of the heart, as well 

 as to exhaustion of the organ. If the pulse of the horse 

 exceeds SO it is usually irregular. Irregularity is also ob- 

 served in valvular diseases of the heart, and in myocarditis. 



The pulse is intermittent when a beat fails now and 

 then. When regularly intermittent, a certain beat can not 

 be felt, as for instance, every fourth or fifth pulse wave ; when 

 irregularly intermittent there is a lapse which does not occur 

 between any certain beats. Sometimes the heart's beat is 

 synchronous with the intermittency of the pulse ; at other 

 times the heart's beat is normal, the intermittency occurring 

 only in the peripheral vessels. To determine this the radial 

 pulse and heart's beat can be compared. 



The intermittent pulse is commonly physiological, and 

 seen in perfectly healthy horses and dogs, where it disappears 

 after exercise and, therefore, probably due to lacking innerva- 

 tion. Pathologically it appears in chronic hydrocephalus 

 (dummies), severe gastric troubles, and during convales- 

 cence from infectious diseases which have occasioned high 

 pulse (contagious pleuropneumonia of the horse). 



