Just like we have
done with aortic stenosis. Once again here
it is important that your physiology is solid.
A couple of things here I am going to point out
to you that without a doubt you should not
be able to miss. Let's continue here. Let us begin at the first point.
You see where it says diastolic blood pressure, so here
we are comparing once again, our left ventricular
pressure curve to
the aortic pressure curve. I want you to
notice right off the bat, is there any discrepancy
between the left ventricular pressure curve
and the aortic pressure curve on your left
graph? No there isn’t. Because that should
be in parallel meaning to say when the left
ventricle is ejecting blood into the aorta,
the pressure between the two chambers, left
ventricle and the aorta should be synonymous, should be
in parallel, should be in synchrony. And it is, even here. So
that's not my issue, it is not aortic stenosis.
You want to go back and take a look at aortic
stenosis. There is a huge discrepancy between
those two curves, here we don’t see that
and so we know it is not aortic stenosis.
Next, where is my issue, you tell me, when is the aortic
valve supposed to close? EC versus S2, right
underneath S2 is where that aortic valve is
supposed to close. That is the beginning of
diastole. Isn’t that? And that is when the
aortic valve closes but it can’t that is
my problem, aortic regurg. So right after
S2, there is an early diastolic murmur because
that is exactly at the point where the pathology
begins. Once you understand that, then we can
walk through some of the other important points
such as, well let's pay attention. You see where it says diastolic
blood pressure, on your left curve and I want
you to go to the pressure-volume loop on your right side. They are
also diastolic blood pressure. They are the same exact points
physiologically but the manner in which it
is presented is a bit different clinically
it is so important, it is so significant, not a point in which
you can just brush off. Is that clear? Why? Let
us begin. I want to walk you through the pressure-volume
loop first and then I will take you through
the left ventricle pressure curve. The pressure-volume
loop versus diastolic blood pressure, what
is that vertical line? Isovolumetric contraction.
The red dash line A, the loop A is the normal,
not the line but the red dash curve, that is normal.
That's isovolumetric contraction, that's normal. And you are building
enough pressure so that you can do what please?
So that you can then eject, open up that aortic
valve. Would you tell me what that pressure
should be? Take your time. What is that pressure that you
are going to develop so that you can open
up that aortic valve normally? Is it 120 or
80? It is 80. Now, take a look at the pressure
curve on the left. You see the top, the left
ventricular pressure curve, the top, the tip,
the pinnacle? That should be what pressure
please? In physio, you learn that as being 120.
What is the pressure in which the aortic valve
should open? That should be 80. Now you tell me, close your eyes,
120/80, what does 80 mean to you? Even though it is a systolic
pressure or a systolic process, that 80 represents
actual diastolic blood pressure. You see the
significance of that. Now you might have looked
at it in physio clinically how important is this. Really important.
In aortic regurg how easy is it for you to
open up that aortic valve? It is not easy,
that is why your patient has a bounding pulses.
Cannot be anymore dramatic. And so, therefore, you
don't have to reach 80 to open up that aortic valve.
Maybe drop down to 60, maybe even 50.
Now, you tell me what is the significance
of the diastolic blood pressure in both of these
curves? Dramatically decreased. I want you
to take a look at the pressure-volume loop
on your right and the B curve, EC versus diastolic
blood pressure, I want you to compare that point
to the normal which is the red curve and you
have your diastolic blood pressure which is
normally at 80 and you find that to be decreased.
Clinically how important is that? If you ask
any cardiologist aortic regurg, diastolic
blood pressure being dramatically decreased
is point number one as being the most important
diagnostic indicator. What is point number
number 2? When you decrease the diastolic blood
pressure so much then you tell me what pulse
pressure equals. Pulse pressure equals your
systolic blood pressure minus your diastolic
blood pressure, right? And what if it diastolic blood
pressure decreases like crazy? What happens
to pulse pressure? It increases like crazy. Now that I can't help you,
that's just simple math. When you decrease the diastolic blood pressure
like crazy and in the formula for pulse pressure,
your pulse pressure increases. The two most
important parameters for aortic regurg is
the dramatic decrease in diastolic blood pressure
and an increase in pulse pressure. So far so good, I hope.
One last little point that I need to bring
up. You see where that those green line in your pressure-volume
loop, A and B. Those green lines represent,
you see the beginning of B and A, and there
is where your aortic valve should close and
in aortic regurg it doesn’t close. If your aortic valve doesn't close,
then what happens to isovolumetric relaxation?
You see the red dash curve and it is moving
down, that is normal isovolumetric relaxation.
In aortic regurg, you don’t have it. On
your exam whatever it may be, understand all
that they have to give you is a lack or deficiency
of your isovolumetric relaxation and that
to you ladies and gentlemen is aortic regurg.
You understand this physio here, you understand
the pathogenesis that I have given you and
I have given you the presentation of the patient.
How could you miss a single question? How
could you never be embarrassed. In fact
whenever you are attending in a rotation
and a cardiologist is asking you question
you are not going to be hiding in the back,
you are going to be the individual moving
up in the front and confidently telling them what?
"This is aortic regurg doc, and this is why.
Here are my differentials. This is what is
going on with diastolic blood pressure, this
is what is going on with pulse pressure."