24 



Record no. 17. 



The waves of the radial and oi the ven- 

 ous pulses are found in this tracing. The 

 radial pulse shows a very clear bigeminism. 

 At the right side of the tracing there are 

 regular waves of the dominant rhythm to 

 be seen. The bigeminism arises from the 

 succession of ventricular extrasystoles in 

 alternating cycles. The venous tracing con- 

 firms this interpretation, the auricular waves 

 fall rhythmically; at one time the ventricular 

 wave preceding the normal beat at, another 

 succeeding that of the premature one, fall- 

 ing in the final phase of the systole of the 

 latter. 



Observation no. 19. 



Bigeminism from nodal extrasystoles. In- 

 terpolated extrasystole. Atropine test with 

 change of condiictibility. 



J. Q. R.; white, 25 years, old, male, 

 tradesman, resident at Sant'Anna dos Alegres. 

 Previous history, merely different attacks of 

 colds and bronchitis a frigore. Denies hav- 

 ing h id venereal or malarial history. About 

 five years ago a bediming of ankylostomiasis 

 with pains in the legs and fatigue, which 

 was cured. He lias felt ill for about a year, 

 and lias had attacks of precordial strong 

 a'.d rapid beats. At first short and far be- 

 tween, these attacks have become more in- 

 tense, more frequent and of longer duration. 

 They are brought on by the slightest emo- 

 tion or effort or even come on without any 

 provocation. They are independent of meals. 

 Sometimes they come on at night and the 

 patient wakes up with a start. They are very 

 uncomfortable and bring on uneasiness, spots 

 before the eyes, sweating, trembling, labored 

 breathing and strong agony (avexame). The 

 patient does not mention giddiness. For 

 about two months he has had a feeling 

 of fatigue after any effort, even after the 

 slight exercise of walking, which brings on 

 tiredness, palpitation and pains in the legs. 

 He does not mention edema, nor has he 

 any. Heart enlarged, apex beat in the fifth 



intercostal space outside the mammillary line. 

 Right margin 2,5 cm. from the midsternal 

 line. Sounds without noticeable change. No 

 murmurs. Extrasystoles with bigeminal ap- 

 pearance. 72 to 80 pulsations- Tmx.=135. 

 Atropine test. Liver not enlarged. Thyroid 

 enlarged. Inguinal glands not enlarged. Ner- 

 vous system negative. 



Record no. 18. 



Tracing / was taken before the injection 

 of atropine. The tracing of heart and pulse 

 which are analogous shov,^ waves in bi- 

 geminal groups interpolated with regular 

 waves of the dominant rhythm between. 

 The second wave of the bigeminal group 

 is of extrasystolic appearance; the jugulir 

 tracing shows that they are "nodal extra- 

 systoles"; the auricular and ventricular con- 

 tractions are premature and synchronous. 

 The dominant rhythm is slow; the jugular 

 curve tracing is peculiar as it shows a bifid 

 V wave and very clear Hirschfeld C waves. 

 The a wave of the dominant rhythm which 

 follows the extrasystole is slightly anticipat- 

 ed. 



Summary: bigeminism caused by nodal 

 extrasystole. 



Record no. I8-A 



Taken fifteen minutes after the injection 

 of atropine. 



The pulse has become regular, but not 

 entirely so. The a waves do not succeed 

 each other in perfectly regular rhythm; an 

 extrnsystole corresponding to f' v' of the 

 venous curve is to be seen. 



Record no. 18B 



Taken one hour after atropine. The 

 beats are slightly accelerated and are becom- 

 ing rhythmic. 



Record no. 18-C 



Taken four hours after atropine. The 

 pulse has again become irregular though it 

 still is accelerated. The a waves succeed 

 each other irregularly. Some are blocked, 



