39 



The block is consequently in 2:1 rhythm . 

 In some cycles, for example in F, the rhythm 

 returns to 1:1 with the a c interval much 

 lengthened. 



The beats of cycle P are probably ex- 

 trasystolic and of ventricular origin. 



Record no. 40-A (II). 



The injection of 1 milligram of atropine 

 did not improve the conductibîlity; the block 

 persists in 2: 1 rhythm. 



Record no. 40 B (III). 



The auricular rate has become slower - 

 84 instead of 107 beats; conductibility im- 

 proved, cycles of I ; 1 rhythm with a c in- 

 terval much lengthened. At some points the 

 block reappears in 2: 1 rhythm. Some beats, 

 such as those of cycle XIII, are frankly 

 extrasystolic and of nodal origin, both the 

 auricular and ventricular beats being pre- 

 mature. On the heart tracing the auricular 

 waves are seen very clearly. 



Observation no. 42. 



Partial block 2 

 Sudden aeaih. 



1. Cardiac insufficiency. 



M. D. 1V\., white, male, 52 years, married, 

 resident at Porto Manga. 



Examined October 14, 1912. Previous 

 history. The patient mentioned attacks of 

 malaria and venereal chancres, but not 

 rheumatism. He has been ill for about 12 

 years with fatigue, edema and sensation of 

 gastric distension. He has had no attacks, 

 or palpitation, either now or before, and is 

 a well-grown man of robust constitution. 

 Very marked paleness; general edema, more 

 marked in face and lower limbs. Coughs 

 and has dyspnea on exertion. Feels no dis- 

 comfort when lying down. Frequent giddi- 

 ness. Heart enlarged, apex beat in the fifth 

 space 11,5 cm. from the midsternal line. 

 Right margin 3,5 cm. from the midsternal 

 line. Base: 15 cm. ; height 8 cm. First sound 

 preceded by a sound and substituted by a 

 prolonged murmur during the whole systole, 

 propagated towards the axillary line and not 



audible at the back. Second sound clear. 

 In the middle of the ventricular diastole is 

 heard a tone accompanied by a slight shock 

 with venous wave in the veins of the neck. 

 These and those of the arms and thorax 

 are turgid. Pulse 36, not varying or only 

 very slightly in different positions. 37. 

 Tmx.=160. The atropine test produced a 

 slight modifcation of pulse, as can be seen 

 in tracings. Liver and spleen very much 

 enlarged with moderate goiter. 



This patient stayed three days in Las- 

 sance and returned afterwards to his home, 

 three leagues away. On arriving he died 

 suddenly. 



Record no. 41. 



October 14, 1912. 



This is a tracing of partial block. There 

 are three very clear waves to be seen in 

 the jugular tracing; 2 of them form an a c 

 group which is repeated in regular periods 

 of 17 tenths; the a c interval is variable; 

 sometimesthere are 2 tenths, sometimes slight- 

 Iv more or even 3. In the midst of each in- 

 terval between 2 a c groups appears an a' 

 wave which is not transmitted to the ventri- 

 cle so that the ventricle beats just twice less 

 often than the auricles. The V wave is 

 slightly marked and in some places does not 

 even show. At some points the wave V is 

 however clear so that it can be marked 

 precisely. The seventh and eighth beats of 

 the tracing show rather anomalous intervals. 

 The seventh is shorter and the ninth longer; 

 one might suggest an extrasystole followed 

 by a compensating period of rest. The anal- 

 ysis of the jugular pulse shows, however, 

 that it is really a variation in the time of 

 production of the stimulus. The auricular 

 waves appear clearly in regular succession; 

 they are slightlv accelerated in group 7 and 

 retarded in group 8. Tracing 3a taken 20' 

 after injection of l,g001 of atropine shows 

 nothing noteworthy except that the atropine 

 has had no influence either on the auricular 

 or ventricular beats. This has also been 

 noticed by some authors without a satisfac- 

 tory explanation. In tracing IV taken 80 



