Heart Failure Explained Clearly – Remastered
24
September

By Adem Lewis / in , , , , , , , , , , , , , , , , , , /


welcome to another MedCram
lecture we’re gonna talk about heart failure today now sometimes this can be
a little confusing because there’s a lot of different definitions this was known
as congestive heart failure and there’s been some new definitions that have been
introduced that have been a little bit confusing as well and we’re gonna go
over the basics first here in the first lecture and tell you a little bit about
the definitions and also the path of physiology behind heart failure now
generally speaking if you look at the heart and we will symbolize that here
with actual heart remember the heart is just a pump and you’ve got blood going
into it and by definition all blood that goes to the heart must go to the heart
via veins and then you have blood coming out of the heart and by definition those
are arteries now of course in the pulmonic circulation the arteries have
deoxygenated blood and the vein has oxygenated blood and in the systemic
circulation all of the arteries have oxygenated blood and all of the veins
have deoxygenated blood and we’ll talk about that a little bit later but as you
can see the heart is meant to pump blood and have it flowing in the correct
direction generally speaking if you have heart
failure you’re not going to get as much blood going forward and you’re not going
to get as much blood going in and so as a result the two major types of symptoms
that you’re gonna see in heart failure is not enough forward flow and because
there’s not enough forward flow blood stays in the heart and as a result of
that blood which should be entering the heart is not entering the heart and as a
result of that you’re going to see congestion before it okay this is like
an accident on the freeway there is no traffic in front of the accident because
there’s not enough forward flow but we certainly know that there’s plenty of
traffic before the accident and there’s quite a bit of
congestion now things would be pretty simple in this situation if this is all
that we had and so we’re gonna get into a little bit more detail but let’s look
at how these symptoms manifest themselves not enough forward flow could
mean number one kidney function decreases just think about all of the
organs which are all of them that rely on blood perfusion and if the kidneys
are not getting enough blood you’re gonna have kidney function decreasing
that of course is going to activate the reno angiotensin system or the Rast
system it will also activate the anti diuretic hormone system of course this
is going to increase the amount of fluid retention that you have and that could
exacerbate your congestive heart failure number two think about your pulmonary
system and think of chain Stokes respirations okay so not enough carbon
dioxide is circulating and therefore you get chained Stokes ventilation where you
breathe fast and then you breathe slow a lot of the symptoms that you see are on
the congestion side and so certainly when you have congestion the first organ
that it goes to is the lung so think of pulmonary edema but if it keeps backing
up you know that the next organ it’s gonna go to is the liver so liver
congestion so you could see the ast and alt go up this is also known as nutmeg
liver because if you do a cross-sectional of the liver it would
look like there is nutmeg you would also get elevated pulmonary artery pressures
and also think of pedal edema so these constellation of symptoms can
be divided in problems associated with poor output and problems associated with
poor input or congestion and in any heart failure you could see
both of these types of symptoms now I want to talk about the heart itself now
the heart we set as a pump but it’s not your typical swimming pool pump which
you just turn on and just runs continuously it actually has two very
distinct actions it has an action of active contraction and it also has an
action of active relaxation and it’s this active relaxation that is the most
misunderstood and so there are two phases of this pump if you will a two
stroke pump where there is one phase called systole and there is another
phase called diastole now systole is where there is active contraction
diastole is when there is active relaxation if you have a problem with
either of these two functions you could get congestive heart failure systole is
when the heart is pumping blood actively into the aorta and to the systemic
circulation and pulmonic circulation when it relaxes however blood enters
from the veins into the heart both the pulmonic vein and also the inferior vena
cava and allows the heart to fill if the heart can’t contract you have something
called systolic dysfunction if the heart can’t relax you have something called
diastolic dysfunction there is something that is known as the ejection fraction
otherwise known as the e F the ejection fraction is simply the size of the
hearts at end diastole in other words the size of the heart when it’s the
largest – the size of the heart at and systole
in other words the size of the heart after it contracts so in other words
what we’re looking at here is how much blood was pumped out of the heart and we
divide it by the size of the heart at the end of diastole so what we’re saying
here is that the ejection fraction is the proportion of blood that the heart
can pump out in one contraction the thing I want you to notice is that if
the heart has a hard time contracting this number up here is going to get
smaller but this number is going to stay the same let’s review that again if
there’s a problem with systole if the heart is too weak to contract then these
numbers are going to be very similar and therefore the difference between them is
going to be very low this number will not change however
and so the ejection fraction will go down in systolic dysfunction
however in diastolic dysfunction remember what the problem is the problem
is is that the heart can’t relax and as a result of the heart not being able to
relax this number will go down and as a result when you have a small heart that
can’t relax there’s not a lot of blood that you can pump out of a small heart
and so therefore what happens in this situation is this will stay about the
same or if it goes down this also goes down and so as a result the ejection
fraction in diastolic dysfunction is about the same it doesn’t change and
this distinction has been made with the new classification let’s talk about that
officially speaking this is the new terminology there’s something called
heart failure due to reduced ejection fraction and then there is heart failure
with normal ejection fraction now if you notice here is the reduced here is the
normal that’s all you really need to look at you know that if you have a
reduced ejection fraction then you have systolic dysfunction and the problem
here is that blood cannot be ejected out of the heart blood can’t get out as a
result of the fact that blood can’t get out then blood can’t get in to the heart
okay now with a normal ejection fraction what’s the problem here the problem is
is that blood can’t get into the hearts because the muscles won’t relax when the
muscles don’t relax they can’t relax enough to allow the
blood to come into the heart during diastole and so here the problem is is
the blood can’t get in and as a result of the fact that the blood can’t get
into the heart the blood can’t come out of the heart the heart can’t pump that
blood out if it’s not getting in blood can’t get out notice you have the same
problems in both types of heart failure but the key is is the why the reason why
you have heart failure due to a normal ejection fraction is because blood can’t
get in the reason why you have heart failure in a reduced ejection fraction
is because blood can’t get out now what are some of the causes of these things
let’s talk about reduced ejection fraction so things that can cause
reduced ejection fraction would be ischemic heart disease so you haven’t
had enough oxygen going to the heart and as a result of that tissue has died and
it’s no longer functional it’s weak if parts of the whole muscle die you can
even have aneurysms of the heart muscle so ischemic heart disease is classic
think of this in coronary artery disease people that have had cabbage people with
diabetes okay so what’s the problem in normal each action fraction well
remember here is that blood can’t get into the heart and the reason why blood
can’t get into the heart is because they’ve had hypertension for so long
that their muscles are so thick that they can’t relax anymore so the big one
here is hypertension almost certainly so think of these in patients with a normal
ejection fraction and they’ve got thickened myocardium left ventricular
hypertrophy these people still benefit from lasix
because remember blood can’t get in therefore blood can’t get out and if
blood can’t get in it’s going to congest into the pulmonary circulation so the
key that I want you to remember here is if you suspect somebody has congestive
heart failure and you get an echocardiogram and the ejection fraction
is greater than 40% you really can’t say that this patient doesn’t have
congestive heart failure because they very well certainly can
they would have heart failure with a normal age ection fraction we’ll talk
later about some of the other aspects of heart failure please join us for our
next video thanks for joining us


13 thoughts on “Heart Failure Explained Clearly – Remastered

  1. I just want to thank u Dr. for that video. My name is Francine P. and i was diagnosed with Chronic Congested Heart Failure this year. And my Heart is pumping only 15%. I've got rush to Stanford Hospital and they saved my life. Now i'm doing good and living with my condition. The main KEY is STICKING to my NO SODIUM DIET and TAKING my MEDS. EVERY DAY and ON TIME. Thanks again i learn alot.

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