520 HANDBOOK OF PHVSIOLOGV ^ CIRCULATION I 



LA 



cm 



A., 



mm 

 Hi 



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v».^ 







RasRc 



LVSW 58 

 PVR .033 



B 

 32 I 



■«5£» 



35 



30 



25 



10 



5 - 



LEFT VENTRICLE 



LA. MEAN cmH^jO 



t ^1 



RIGHT VENTRICLE 



R.A MEAN cmH^O 

 I I L_£_ 



20 



FIG. 25. CSP = carotid artery pressure 

 (generated by pump). LA = mean left atrial 

 pressure. LVSW = left \entricular stroke 

 work. PVR = calculated total peripheral 

 vascular resistance (mm Hg mean aortic pres- 

 sure divided by aortic flow in ml/min). 



Stroke work can be reflexly manipulated in a stepwise 

 manner by making graded changes in the carotid 

 perfusion pressure in much the same way that com- 

 parable changes can be induced by grading the 

 frequency of left stellate stimulation. 



By using the type of sequence shown at tlie right in 



figure 25.-1 and the same over-all approach used in 

 the pre\iously described experiments when examining 

 the effect of graded stellate stimulation (fig. 14), the 

 effect of carotid perfusion pressure on the position of 

 the ventricular function curve (\TCl.\) can be ob- 

 served. Figure 2^8 (left panel) shows that when the 



