Ventricular septal defect | Circulatory System and Disease | NCLEX-RN | Khan Academy

November 18, 2019 0 By Kody Olson


Voiceover: Oh, I could remember
it as it was yesterday. My son was brought into the world. And we were all excited
and there were a lot of things going on, a lot of
emotions all over the place. But one of the things that
I noticed, is that the nurse took him, she started to
clean him off, of course, but then she did something
that was extremely important. She took this little device
that we call a stethoscope. One end was in her ears, and the other one went towards the chest of my little son. And she started to
listen to the heartbeat. And I can imagine that
she was expecting to hear something like this: (healthy heartbeat). Now because we’re dealing with
a newborn baby, of course the heart rate is going to be
significantly faster than that. But the main thing that
she’s listening to is to hear that ‘lub-do, lub-do,
lub-do’, because that tells us something about the
functioning of the heart. Now, what if she were to hear something that sounded like this:
(off-beat heartbeat). Oh, that doesn’t sound as good
as I would like it to sound. It sounds like blood is squirting into a place that it’s not supposed to be going. And that’s exactly what we
see in babies that are born with what is called a
ventricular septal defect. Ventricular septal defect. Septal defect. And what that basically
is, if you break it down, a ventricular reverse to our ventricles. We have a left ventricle,
and a right ventricle. Septul refers to this
structure, this wall. The word septum means wall. And we have a wall between
the left and right ventricle. And a defect is where we have some kind of structural abnormality. And in this case we’re
dealing with a hole in the wall between the
left and right ventricle. And that is called a
ventricular septal defect. Now, what’s going to
happen if an individual is born with a ventricular septal defect? Well, we’re going to have
blood that’s going to be squirting from the
left side into the right. There’s not supposed to be this opening. But if there’s this
opening, once the ventricles contract, the blood is not
only going to go to the rest of the body via this
great vessel that we see here that’s called the
aorta, it’s also going to go in through this opening
to go into the right side. So we’re going to get what we
call a left to right shunt. In other words, blood is
shunting from the left to right, where it’s just squeezing
through that opening. And as it’s squeezing
through that opening, you can imagine, okay,
the blood is flowing, and it’s encountering
turbulence as it’s going through this opening that’s
not supposed to be there. And that is what you hear in that when you listen with a stethoscope. And that is called a holosystolic murmur. Holosystolic murmur. Now, in terms of the
location of this ventricular septal defect, it can be
anywhere along this septum. And the place that we’re
most likely to see it, is higher up where you
can see it’s significantly thinner here than it is down there. And that is called my
membranous… membranous septum. And the reason it’s called
that, when you think about a membrane, you think about
something very thin, right? And this part at the top here,
closer to the atria, we’re going to have a thinner wall
that’s more membrane-like. And that’s called the membranous septum. This is where we’re going
to see it in most cases. And then, lower down, we have the part that we call the, and you probably can guess this, muscular… muscular septum. It’s much thicker. It’s more muscular. And that’s why we call
it the muscular septum. Now, what’s going to happen
when we have this situation? Okay, so we mentioned that blood is going to flow from the left to the right. And of course if it flows from the left to the right, it’s going
to continue on with the rest of the blood to go to our lungs. And although that is a
more inefficient system because we have that
blood just recirculating here, as opposed to going
directly to the rest of the body, it is usually
going to be asymptomatic. So let’s… what color
should I use for that one? Let’s see… I’m running out of colors. So I’m going to go back with my green and just say that it’s usually asymptomatic. So we don’t usually see
significant problems as a result of a small
ventricular septal defect. However, if it’s larger, it can cause some significant problems. So in terms of treatment
then, in most cases, we leave it alone, since it’s going to be asymptomatic and you can live with it. The oxygen levels are adequate. So I’ll put that here with asymptomatic. Oxygen levels adequate. It’s not going to cause a
significant loss of function. But if it’s larger, so
if we have a large hole in the wall, then it can
be treated with surgery. And of course with
surgery, the main goal is to repair that hole so
that the blood no longer moves from the left
side to the right side. So a ventricular septal defect is where we have a defect in the wall. A congenital, meaning the
individual is born with it, hole in the wall between the
left and right ventricle, causing blood to shunt from left to right. Resulting in a holosystolic murmur when you listen to it with a stethoscope. Usually in the membranous septum, but sometimes also in the muscular septum. Normally asymptomatic
because the oxygen levels are adequate, and if it
gets really large, then surgery might be necessary
to repair that hole.