THE CONTROL OF THE FUNCTION OF THE HEART 



L.V.D. 

 cm 



b^ 



P. A. 

 cm 



0"- 

 40 r 



L.A. 

 cm 



250 



Ao. 

 mm 



Hg 





 40 



L.V.D. 



I 5:51^ 



H,0 



1- 



t 



M.S.L. 



u i-zfTtr 



FIG. ig. LA = left atrial pressure, PA = pulmonary artery pressure. 



Stellate ganglion stimulation is the right panel. An 

 increased amplitude of the atrial "a" wave contour is 

 observed during stellate stimulation. It is also ob- 

 served that the duration of atrial systole is shortened 

 suggesting that atrial as well as ventricular power is 



augmented by sympathetic stimulation. The same 

 results are obtained after the intravenous administra- 

 tion of norepinephrine (fig. 19, middle). The left 

 tracing is the control study, and the right tracing 

 during the intravenous administration of norepi- 



