l6o CLINICAL VETERINARY MEDICINE AND SURGERY. 



Previous to the accident for which the horse was sent here no dis- 

 turbance or symptom suggesting cardiac irregularity had been remarked. 

 According to its driver's account the horse even seemed brighter and 

 more spirited than the animals with which it worked. 



In 1894 we discovered similar disturbance in a ten-year-old 

 carriage horse, sent here from the department of the Maine-et-Loire 

 on account of spavin lameness. This horse was very fast and powerful, 

 and had never shown symptoms of heart disease. The pupil who 

 attended it was instructed to keep me informed of the changes in the 

 pulse and heart. The intermittency lasted as long as two complete 

 heart cycles, and occurred after every three or six pulsations, long and 

 short series succeeding one another in an extremely irregular fashion. 



The aetiology of cardiac intermittency is complex, and its pathology 

 even more obscure. In certain cases where it has been observed apart 

 from any manifest organic change it has been attributed to overw^ork 

 or digestive trouble ; but, except when produced by excessive doses of 

 digitalis, it usually indicates some heart disturbance. 



Of the organic lesions it most frequently accompanies myocarditis, 

 at times endocarditis and pericarditis. Its final cause always appears 

 to be either primary or secondary disease of the cardiac muscle, or 

 some disturbance of the nervous apparatus of the heart. On account 

 of intermittency being usually due to myocarditis, it is often accom- 

 panied by other symptoms like dulness, rolling, and doubling of the 

 heart-sounds, which indicate or at least suggest disease of the heart 

 muscle. 



Temporary intermittency, true or false, regular or irregular, often 

 appears during various specific diseases in consequence of the heart 

 being attacked by infectious organisms or their toxins. I have often 

 observed intermittency during pneumonia, and those practitioners who 

 auscultate the heart during such attacks have certainly had similar 

 experience. In the Bulletin de la Societc Ccntrale dc Medecine Vete- 

 rinaire for 1894 I described a case. I may here mention a more 

 recent instance. 



At the commencement of last December I received into hospital a 

 six-year-old horse with acute pneumonia of three days' standing. The 

 disease was of moderate gravity, rather benign in character ; the tem- 

 perature did not exceed 40*5 ° C. (i04'9° F.), and the fever declined on 

 the sixth day. Every morning after having examined the state of the 

 lung I auscultated the heart. During resolution, the tenth day of the 

 attack, I noted intermittency ; a pause, equal in length to that of one 

 cardiac cycle, following series of six to ten contractions, normal in 



