12 QtJAtERCENTENAkV STUDIES IN PATHOLOGY 



And it was soon noted that when this change occurred, the tendency to 

 cardiac irregularity was much greater than in those experiments in which 

 more profound anaesthesia had been induced. Attempts were made to 

 record the changes in the pulse during the operation, but in the experi- 

 ments in which this was done, the irregularity was not developed. In 

 several cases, however, it was noted that the heart rhythm was normal 

 before and during the first part of the operation, but, that when respiratory 

 movements were induced by cutting through the sternum, the pulse, 

 which had previously been of the usual slow vagus type seen in the dog, 

 suddenly became accelerated and irregular. On examination of the 

 heart in those cases, before the apparatus was applied to it, the ventricles 

 were found in rapid, irregular movement ; the relaxation was often very 

 imperfect between three or four successive contractions, and then more 

 complete for one or two beats. The impression was given that the 

 ventricles were responding to a very rapid series of impulses which 

 prevented their diastole, and that they could only relax when their 

 irritability was reduced by fatigue, and then the more complete diastole 

 followed. The auricles were widely dilated, and no systole occurred in 

 them ; they were not wholly paralysed and inactive however, for, on 

 close inspection, the fibres proved to be in a state of continual inco- 

 ordinated contraction, each part of the auricle undergoing continuous 

 fibrillary contraction independent of all the other parts. The heart was, 

 in fact, in the condition known to physiologists as auricular delirium or 

 fibrillary contraction in the auricle. 



Auricular delirium is not infrequently produced by poisonous doses 

 of bodies of the digitalis series,* and is very readily induced by rapid 

 induction shocks passed through the auricular walls in animals. Several 

 papers -|- have appeared recently dealing with the subject from the 

 laboratories of Berne and Brussels, and we also have devoted some 

 attention to it. In this condition, the ventricle beats much more rapidly 

 than normally, and the beats are irregular in rhythm, and vary in the 

 degree of systole and diastole. Stimulation of the vagus, in our experi- 

 ence, which coincides with that of Kronecker and Spallitta, has no effect 



* Cushny, Journal of Exp. Med.^ ii., p. 233. 



t Kronecker and Spallitta. Arch. Internat. de Physiologies ii., p. 223. 

 Philips. Ibid., ii., p. 271. 

 Fredericq. Ibid.^ ii., p. 281. 



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