6 QUATERCENTENARY STUDIES IN PATHOLOGY 



Of the four tracings, those taken at 1*45, 3*45 and 4*45 p.m., indicate 

 marked and continuous irregularity, while the intervening one at 2*45 

 presents a quite satisfactory, regular pulse of about 88 per minute. This 

 rate is considerably above the average for the age of the patient, but is 

 not to be regarded as abnormal.* The slight variations in the intervals 

 between the pulsations are not greater than those observed in normal 

 persons. Auscultation at this time indicated no abnormality in the heart 

 sounds, and, in short, the heart and circulation at this time appeared 

 perfectly normal. 



The tracings taken before and after this period of regularity offer a 

 marked contrast, the pulse showing great arhythmia and great variations 

 in the strength of the beats. The general character of the tracings shows 

 a number of large pulsations occurring at irregular intervals, and having 

 interspersed among them smaller pulsations sometimes singly, at other 

 times in twos or threes or in groups of larger numbers. Examination 

 shows that the large excursions of the lever are not so simple as they 

 appear at first sight. For example, in Fig. i, the descent following the 

 second and third rise of the lever is interrupted by oscillations which are 

 obviously due to a beat of the pulse in each case too weak to make a 

 more definite record. This is perhaps better shown in Fig. 3, in which at 

 a and b the large excursion of the lever is followed by a weaker contrac- 

 tion, while at d the descent of the lever only shows a slight oscillation, 

 yet there can be no question that there was here a secondary contraction, 

 similar in character to those at a and b, but so weak that it failed to 

 cause even such a beat as is recorded in ^. In the interval c, on the 

 other hand, there was probably no interposed systole of the ventricle. 

 When the stethoscope was applied over the heart there was found a 

 duplication of the first sound in such intervals as have been recorded at 

 a^ b and d, while there was no such duplication at c. At ^, Fig. 3, two 

 small elevations follow each other, and at /, a third one occurred which 

 was too feeble to do more than arrest the fall of the lever for a moment. 

 A little later, in Fig. 3, a succession of eleven rapid weak contractions are 

 seen. Counting these weak and almost unrecorded contractions, the 

 pulse is found to be beating in the irregular periods at 140-150 a minute. 

 On auscultation the heart sounds were found to be very much more 



* Mackenzie. The study of the pulse, p. 53. 

 (100) 



