00:00
Let us take a look at diastolic dysfunction.
Now there is a lot there with systolic dysfunction.
00:04
We did a lot of integration. It is imperative
that you know all of this. Spend a little
bit of time with what I have told you. Review
how to integrate everything and you will be
in great shape. It can’t shake you ever.
So with diastolic dysfunction, what
is going on here? It is the fact the left
ventricle is becoming thickened, why? Well,
maybe there is increased pressure. Why?
Maybe there is hypertension, either primary
or secondary, usually it is primary, much more
common, 95 percent of the time. And maybe aortic
stenosis. And now at this point, the left ventricle
is undergoing what is known as concentric
hypertrophy, and so therefore cannot properly
fill up the left ventricle. We have diastolic
dysfunction. And could you have preservation of your
ejection fraction? Sure you can. Diastolic
dysfunction well. We have more and more understanding
and hence why it's so important for you to make
sure you distinguish between systolic and
diastolic dysfunction.
01:01
Now, couple of things here that become important
once again to bring in a little bit of physio.
01:07
Let us begin. So here let me set this up for
you. On these graphs that you are seeing, couple
of important curves that you are paying attention
to. We are strictly dealing with diastole.
01:20
Now, this first curve that you are seeing
on top represents the aortic pressure and
the left ventricular pressure and you'll
noticed that we are now moving down. The only
thing that this is showing is the relevance
of diastolic interval or diastole with your cardiac
cycle along with left ventricular volume.
This is really important for you to understand
because well, any exam or any attending might
then ask you what is going on with diastole?
Why is this true? Well, first and foremost,
once we begin isovolumetric relaxation, here you
come down and where it says your AVC
at the bottom of that graph, that's your aortic valve
closure. Welcome to what heart sound? Second
heart sound. Are you now clear about where
we are? You have just closed your aortic valve.
What are you going to begin? You tell me.
02:13
Isovolumetric relaxation. So isovolumetric
relaxation and you are moving down this hill
very very quickly. And as you do so, what is
going to happen when your left ventricular
pressure is below your left atrial pressure?
MVO is mitral valve opening, and as soon as
that mitral valve opens, the blood from the
left atrium is going to gush into left ventricle.
02:36
It cannot be any more dramatic. So now what
happens? You are going to find a rise in
left ventricular pressure as you do there. And
right now everything that you are seeing is
in red, everything you seeing in red
represents diastole. The bottom picture represents
left ventricular volume. So as the blood quickly
comes into left ventricle as soon as the mitral
valve opens, guess what happens to left ventricular
volume? Obviously increased. And in the mean
time the atria is just completely emptying,
and as you move
all the way to the right and you are just
about to start your systole and just about
to start your isovolumetric contraction, you
will have your a-wave, which kicks in the
last bit of blood, right. Your a-wave and
then you have your mitral valve here closure,
at the beginning of your isovolumetric contraction.
Please make sure that you are completely comfortable
of integrating the different curves of your
cardiac cycle. It is imperative that you do
that please. Otherwise, you might be asked questions,
you might be put into situations from the
graph while you are spending time perhaps
even wasting it where every second is so incredibly
precious.