J. ROSENWEIG AND S. CHATTERJEE 
137 
HEMODYNAMIC EFFECTS Of COUmPPULSATION 
Aortic Diastolic Pressure 
[legated 
Reduced Coronary 
I/3SC. Rests. 
CoronaryFlow 
Increesfd 
Increased 
Cardiac Output 
Coronary Collateral CircuL 
Increased 
Myocardial Ischemia 
CSae of Infarct) 
Decreased 
Myocardial Oi Tension 
Increased 
Myocardial Aerobic Metabolism 
Restored 
Ventricular Irritability 
Depressed 
Myocardial Contractility 
Improved 
Figure 17. — (b) elevating aortic diastolic pressure. 
Dr. Chatterjee: I agree with you that dogs 
have potential collateral channels, as I have 
shown in my experiment. As for your question 
about humans: I do not want to go into the 
human experiences of counterpulsation. Today 
we have shown by angiogram that there is im- 
provement in collateral circulation. 
Dr. Somani: I was trying to find out if the 
same mechanism is operative in humans. The 
question is: If counterpulsation does increase 
collateral flow in humans, is this due to the 
opening of preexisting channels or to some 
other mechanism? 
Dr. Chatterjee: Counterpulsation probably 
helps in two ways: First, by increasing dia- 
stolic pressure, it improves the coronary artery 
flow and secondly, at the same time it reduces 
systolic pressure and the afterload of the heart. 
Lloyd G. Phillips, University of Minnesota, 
Minneapolis, Minn. : Did you have an opportun- 
ity to dissect the main trunk of the left coronary 
artery and thus obviate the effects of the septa 
branch and also of the left diagonal branch? 
Dr. Chatterjee : Well, we dissected the ori- 
gins of the anterior descending and the sinistra 
coronary artery. We did not dissect the left 
main coronary artery purposely. 
Dr. M. R. Malinow, Beaverton, Oregon: I 
was much impressed by the acute results of 
counterpulsation. How long did you counter- 
pulsate your dogs in the first study? 
Dr. Chatterjee : In our first study, we coun- 
terpulsated for one hour, but in balloon coun- 
terpulsation we counterpulsated four hours. 
Dr. Malinow : It is a little intriguing to spec- 
ulate on how one or four hours of counterpulsa- 
tion can modify the results twenty or thirty 
days later. Are these studies done under anes- 
thesia? How long does anesthesia last and are 
the control dogs also anesthetized for the same 
period of time? 
Dr. Chatterjee: Yes, the experiments are 
carried out under general anesthesia and the 
experimental environments for both the control 
and the treated dogs were more or less the same. 
Questioner : Were the dogs anesthetized for 
the same period of time? 
Dr. Chatterjee: Yes. 
E. L. Stanley, Cox Heart Institute, Ketter- 
ing, Ohio: Concerning the first study, were 
aortic pressures measured in the root of the 
aorta during that short period of time prior 
to pulsation? I can understand that there is a 
drop in the pressure with shock, but was there a 
real drop in aortic pressure in the first study 
prior to pulsation? 
Dr. Chatterjee: The catheters were passed 
through the brachial artery to the aortic root in 
the first study. 
Dr. Stanley : My question is : Did you meas- 
ure the diastolic pressure? Did a decrease in- 
deed occur shortly after placing the ameroid 
constrictors around the vessels? Was there a 
drop in aortic root pressure in the first study? 
Dr. Chatterjee: In the first study we did 
not measure the aortic root pressure in the 
control dogs. In the counterpulsated dogs we 
did measure the aortic route pressure. 
Dr. Stanley : During pulsation or before pul- 
sation? 
Dr. Chatterjee: Before, after, and during 
counterpulsation. 
