see this dilatation of the left ventricle.
Now, again, we talked about the different
kinds of heart failure - systolic and diastolic,
but sometimes there are definitions based
upon which ventricle is in the most trouble.
Most common is left sided heart failure. That’s
because the left ventricle has been injured,
but in some conditions such as severe lung
disease with high pressures in the lung, you
may just see isolated right sided heart failure.
So, let’s think about this for a moment.
With left sided heart failure, the backup
is going to be into the lungs. Patients get
fluid in the lungs and they’re short of
breath. So, the edema is in the lungs with
left sided heart failure.
With right sided heart failure, the backup
is into the veins. So, you often see patients
with fluid in the abdomen, fluid in the legs,
so called peripheral edema and the left ventricle
may be working just fine, but it’s not getting
any blood from the right ventricle because
the right ventricle is failing. And of course,
it’s obvious, what the left ventricle puts
out depends on what the right ventricle puts
out. They have to balance out. If they don’t
balance out, all the blood is going to end
up on one side of the circulation or the other.
And then we’ve talked about before, systolic
heart failure - failure of contraction; diastolic
heart failure - failure of relaxation.
Here’s just a little diagram to remind you
how the whole body is a co-ordinated system.
You see the brain is connected to the heart,
the brain is connected to the kidneys, they're
all connected to the peripheral blood
vessels, and as we’ve talked about, when
there’s heart failure or when there’s
dehydration or when there’s hemorrhage,
all of these factors become activated in an
attempt to - A. Restore the blood volume and
B. Restore the pumping ability of the heart.
And here they are all listed again, just as
we’ve talked about before, the central nervous
system is critical. Sympathetic nervous system
is activated. The kidney through the renin-angiotensin
system is activated and the ventricle is…
gets increased volume and therefore, uses
the Starling mechanism. All of these things
work together. They work great if the patient’s
blood volume is down because of dehydration
and hemorrhage; they work against you when
the problem is that the heart is not pumping
And again, here you see a diagram that just
shows you how all of these interact, how decreased
cardiac output can lead to lung congestion
and how increased peripheral pressure can
lead to peripheral edema. The neurohormonal
activations through the kidney that go on,
all of these things are working in a complete
circus motion like the horse riding around
the track in the circus. Around and around,
they keep reinforcing each other and unfortunately,
in heart failure lead to marked retention
of water and salt that leads to the various
symptoms that the heart failure patient has.
The American Heart Association guidelines
talk about various levels of heart failure.
Level A is somebody who’s really predisposed
to heart failure, but has not developed it
yet. So, that’s somebody with high blood
pressure, diabetes, hypercholesterolemia -
hyperlipidemia, as we’ve talked about, that
leads to atherosclerosis. Heart failure hasn’t
developed yet, but the substrate, if you will,
is ready to go on and cause a heart condition
that will lead to heart failure.
Grade B is when you’re starting to have
some very early signs of heart failure by
some of our fancy test such as from the echocardiogram,
but the patient is still asymptomatic.
Stage C is when the patient is already having
symptoms. They’re tired, they’re short
of breath, they have peripheral edema. And
stage D is when they’re really incapacitated
with heart failure, marked severe symptoms
of heart failure.