13 



forms of alterations of rhythm. Can sudden 

 death in the disease depend upon the extra- 

 systoles and upon these exclusively? We 

 must remember that the compensatory 

 pauses of the extrasystolic contractions and 

 their inefficiency in the propulsion of the 

 blood certainly cause profound circulatory 

 embarrassment that frequently determines 

 the occurrence of faintness, vertigo, loss of 

 consciousness and syncopal attacks, etc. In 

 this disease, as our accumulated mass of ob- 

 servations on lhe heart amply demonstrate, 

 the alterations of excitability of the myo- 

 cardium are profound, and as a result ex- 

 trasystoles occur sometimes very frequently, 

 repeated two or three times in the same 

 cardiac cycle. Hence in many cases pro- 

 found circulatory alterations inter»'ene inthe 

 nervous centers of the myocardium itself, 

 and these may explain the sudden death. 

 This is an hypothesis. 



There at once occurs to us another hy- 

 pothesis, also based on fact and perhaps 

 more in accordance with cardiac physio- 

 pathology. Auricular fibrillation has been 

 found in this disease and we believe it is 

 not a rare process although relatively less 

 frequent. While limited to the auricle this al- 

 teration does not impede the circulatory 

 efficiency ; but propagated to the ventricle, 

 as it may be, there soon occurs a failure of 

 the circulation and as a direct consequence 

 rapid death. Is this true in the cardiac 

 form ? 



Let us discuss it briefly. The frequence 

 of ventricular extrasystoles and their repet- 

 ition two or three times in the same cycle 

 express an irritability of the ventricular 

 myocardium, a condition very near to that 

 produced experimentally and indicated by a 

 fibrillar state of the muscle. One degree 

 further in the pathologic process and the ex- 

 citability of the ventricle will perhaps reach 

 a condition similar to that of the auricle, 

 with the terminal failure of the rhythm. 

 Moreover, we have the opportunity to ex- 

 hibit tracings in which the ventricular ex- 

 trasystoles, up to seven in number and all 



abortive, are repeated in the same cardiac 

 cycle. The extrasystolic contractions here 

 are so weak that they look like simple tre- 

 mors of the muscle and are completely use- 

 less in the circulatory mechanism. 



We must at once refer to MacWilliam's 

 hypothesis which has formed the basis for 

 our argument and in which sudden death 

 in intense disorders of rhythm would be 

 explicable by fibrillation of the ventricle. 



DEATH IN AGONY (MORTE AGÓNICA) 



Here with greater frequence the essen- 

 tial fact is the progressive insufficiency of 

 the myocardium from which asystole results. 

 This insufficiency is principally of cardiac ori- 

 gin, and the renal apparatus, whose functions 

 are little if any affected in this disease, does 

 not particate in its occurrence. In this way 

 the greater number of patients of the car- 

 diac form die, in acute or chronic asystole, 

 from rapid dilatation of the ventricles, and 

 others die from progressive exhaustion of 

 the muscle. 



Another aspect of death in agony is 

 observed by the diminution of the idio-ven- 

 tricular beats, with long diastolic pauses. 

 We have observed one case of this kind in 

 which the ventricular rhythm fell slowly to 

 the minimum of five pulsations per minute 

 or with diastolic pauses of twelve seconds. 



These are the commonest conditions of 

 death in the cardiac form. 



We have only considered the facts of 

 greatest frequence and have left aside other 

 occurrences such as fatal accidents in chil- 

 dren with symptomatic tachycardia, _ defic- 

 iencies of conductibility with partial block, 

 profound alterations of contractibility, etc. 

 Death may here result from various condi- 

 tions aside from those most frequent ones, 

 as is not difficult to understand when we 

 know the intense lesions that attack the 

 muscle. 



Influence of atropine on the alterations 

 of cardiac rhythm in the disease. 



The results of the experiments perform- 

 ed by one of us relative to the action of 



