I HAPTER XVIII 

 THE PI MPING A' TK >N I 'I THE HEART I ont'd 



THE CONTOUR OF THE INTRACARDIAC CURVES 



The Ventricular Curve 



rrom an analysis of tli utour of each curve, further ii 



points are broughl to light The ventricular cun e in the diagram allu 



li<>\\ ii as having a flal top or plateau. B 

 of the more modern, optically recording, instruments i1 

 thai this plateau becomes displaced by ;i peak if every ; ition is 



taken to prei ent dulling dov n of the pressure changes in tl ■ 

 as l.\ opening wide the stopcock in the instrument I 

 is, however, by do means a sharp one, bo thai we may fitlj ibe th<- 



contour "t' the ventricular curve during the Bphygmic peri( 

 ing of a rising portion, almosl continuous with the curve during 

 sphygmic period, ;i summit and then a declining po , which is usually 

 Blower than the ascending. The practical value arising from a stud] 

 curves li<'s in the insighl which they •_: i \ < ■ us into the nature 

 of the cardiac pump They Bhow ns thai tin- impulse which the ventr 

 gives tu the moving mass of l»l*»«»»l in the aorta is a sudden rather thi 



tained one The column "f l>h><».l in the aorta is a 1 1 1 i •_: 1 1 1 \ thing 

 i!iu\<\ and it would appear as it' a sustained broughl to 1 •■ 



it during the Bphygmic period would be far more efficienl in !»• 

 about an adequate movemenl of the blood than a Budden ,:• Ii 



a heav) L r at<' a bIon sustained pressure is 

 sudden bloM 



l • is further <>f inl 

 that there is \ erj little indication of an; 

 at the moment during which the semilunar 



erthcless, \<y close Bcrutinj ii <-.m usually 

 change in the direction of t h< 

 open and similarly thai the mom< 



i>> a Bharper bend in the cui v< is a matt 

 thai thi ontour of the cu iring I 



partly "D the de 

 •l\ on th' 



