( 83 ) 



proved. Where under influence of digitalis dyalisata the tendency 

 of tlic cardiac muscle to dissociation, as we saw above, is accen- 

 tuated, there we could expect that it' we combine this influence 

 with the equally dissociating' vagus influence, the evidence of dis- 

 sociation also in the ventricle might come out. Indeed, during the 

 influence of the vagus nerve on such an intoxicated heart, I found 

 a curve which is apt to illustrate this dissociation. We have here 

 to deal with the transition of an alternating' pulse into a normal one, 

 after a direct vagus stimulation and shortly after the inundation of 

 the entire heart by a physiological salt solution (In the ventricular 

 curve this is visible). 



In my mind there is no doubt, that the small elevation after the 

 reduced ventricular contraction cannot he interpreted, either as an 

 auricular contraction because nowhere in this or other tracings an 

 A s of this considerable height was observed) nor as an ordinary 

 extra-systole of the ventricle. In the latter case it could not be 

 explained not only why here an extra systole arose, nor why the 

 preceding ventricular contraction coming at the right time, was so 

 exceedingly diminished in size. We have here undoubtedly to do with 

 a dissociation in time of two parts of the ventricular musculature 

 (eventually also of the "Reizleilungssystem") and only when after 

 ///r pulsus altemans a not completely synchronic contraction of these 

 parts has taken place, and the entire musculature comes again at the 

 same time in the refractory period, normal contractions can follow. 

 According to this interpretation the difference between the great and 

 the small contractions of the preceding 1'. A. is to be ascribed to 

 the fad, that only in the ureal contractions a particular pari of the 

 muscular mass is reached by the contraction wave; whereas this 

 part of the muscle is excluded from the contraction in the small V~ s . 



Fourth ['arm of P. A. with retarded great contraction. 



Of this type of I'. A. I ca t adduce any curve met with in 



lower animals. The only specimen I have come across, is registered 

 from a case of Basedow, who suffered from an exceedingly rapid 

 and at the same time irregular heartbeat. Il appears to me that here 

 we have to deal with an automatically beating ventricle or better 

 with a ventricle, in whom two divisions are beating independently, 

 only every other V s (the greater one) causing an antiperistaltic con- 

 traction reaching the auricle. Comparable curves have been published 

 by Mackensie *) and Wenckebach*), so that its occurrence in men can 



') Mackenzie, British medical Journal, 1905, 111. Com p. tig. 12 perhaps also fig. 5. 

 ~) Wenckebach, Arhythmie. 1903. P. 107. 



