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DISCUSSION 
Chairman La Farge: Thank you Dr. Mali- 
now. The floor is open to discussion. I'd like to 
question Dr. Malinow a little more about the 
clinical applicability of the model in question. 
This is a very neat model. It uses aortic, sys- 
tolic, diastolic and mean pressures, but unfor- 
tunately, from a clinical standpoint, calls upon 
aortic flow which is very difficult, if not impos- 
sible to measure in the post-operative surgical 
patient, unless one uses, for example, cardiac 
green dye curves. Can you do without the flow 
term? Have you tried to apply this clinically? 
Dr. Malinow : Yes Dr. LaFarge. I tried here 
to show our best prediction which was 100% 
for the cardiogenic shock but we also did the 
same study without using flow and we obtained 
almost the same result. We were able to predict 
almost 80% of the outcome in cases of cardi- 
ogenic shock just by using pressure. 
Sidney Cassin, University of Florida: I 
think you indicated that you used 50,000 
spheres for injection and somewhere 100 to 
150,000. Is this correct? Did you notice any ef- 
fect of the spheres on the myocardium per se? 
Was there any plugging that was obvious in 
terms of ECG or pathology post-injection — 
since you initially produced an ischemia and 
then injected the spheres? Is this correct? 
Dr. Malinow: Microspheres did not change 
the hemodynamics of the preparation. As you 
know the method for the detection of the spheres 
is by calcination of the whole tissues ; obviously, 
we could not do a histological study. So we have 
not done histological studies in the animals that 
were injected with the microspheres, and we 
were not able to detect any obvious hemody- 
namic differences as compared to those which 
have not been injected with microspheres. 
Chairman: I'd like to add a comment: most 
people who have used single or multiple isotopes 
for coronary flow distribution studies, use them 
in such small quantities that in our hands and 
in the hands of Julian Hoffman on the West 
Coast, we have certainly not seen any changes 
in myocardial performance. The question is : is 
this a double insult? In order of magnitude, the 
insult of the snare is at least greater, I suspect, 
than the insult of the beads. 
