As you can see if I pull the heart
up out of this you can truly see it is sitting in an amazing sac.
Again, that we call the pericardium. Welcome to the lab everyone! Today we're going to talk
about why hearts are in a sac! And not really this sack — really just the sac
that's inside your chest called the pericardium. And we're gonna open the pericardium, pull the heart up, and look at this
sac and the heart in all of its glory. It'll be like an anatomical opening of a Christmas present — even though we're
nowhere near Christmas time... We need to talk about why this
pericardial sac is so important and what happens if something goes wrong with it. So, as always — let's jump right
into this anatomical awesomeness! So I may or may not have been accused of being
a little long-winded with my introductions... So let's not waste any time and go straight
into this thoracic dissection that we have here. You can see a lung on either side here and
then this tissue that I'm running my finger on. And this is what we're talking about
— this is the fibrous pericardium. Spoiler alert! There's going to be a heart inside of this, so we might as well open up this little
"Anatomical Gift" to take a look. And as you can see... [dun, dun, dun...] Sorry — that was a shameless sound effect. I'm acting like I've never done this
before, but I do it all the time, and I make sound effects for the
students because it is awesome! As you can see if I pull the heart up out of this,
you can truly see it is sitting in an amazing sac. Again, that we call the pericardium. Now we need to talk about a
couple of details that helps us understand the function of this pericardium. Now one of the first things we need to address
before we can fully understand and appreciate the pericardium or the pericardial sac is that
this thing is actually two layers fused together. So if I fold it back over the heart, this outer portion is one layer and
this inner portion is another layer. And again, they're fused together. This outer portion or outer layer
is known as the fibrous pericardium, because it's made of a dense
irregular connective tissue. This is a tough tissue that
helps protect the heart and even anchor and hold it in place
because you don't want this thing just bouncing or wiggling around while
it's beating all over the place, right? Now the inner layer is obviously going to have a
different name and as we reflect that back again you can see this is a more glossy tissue. If I pull this away as well — this is called
the serous pericardium because it's made out of a serous membrane that secretes
something important called serous fluid. I said serous a lot there... But this serous fluid is an oily fluid
that gets in this space here that helps reduce friction between the outer portion of
the sac and the actual lining of the heart. So when the heart's beating, when
you're running around exercising getting your heart rate up, you
can have this reduction in friction and not cause a problem between the
heart and the surrounding tissue. Now before we go into the problems
that can occur with the pericardium, we need to talk a little bit more about the serous
pericardium because anatomists love naming things. And this actually makes a lot
of sense because they need to make some distinctions between some layers here. Now remember, the serous pericardium is
fused to the fibrous pericardium here. But the serous pericardium actually blends on and
attaches to the outer layer of the heart as well. It's continuous from here onto the heart tissue. So of course the anatomists are like,
"we gotta name the part that's on the heart versus the part that's attached
to the fibrous pericardium out here..." Now the part that's on the inside lining
of the fibrous pericardium here is called the parietal pericardium. Now that's a subset of the serous pericardium. And parietal just means wall. The part that blends on and literally attaches to
the outside of the heart is called the visceral pericardium, because visceral
just means internal organs. So really what you're reducing friction
between is the parietal pericardium here and the visceral pericardium here with
a little bit of fluid in between there. So I know — that's pure anatomical awesomeness! So what happens when there's a
problem where the sac is inflamed? What causes it? Is it serious, and can we treat it? Well a lot of you've probably heard of this
disorder before, and it's called pericarditis. -itis just refers to inflammation. And if the sac gets inflamed — you might guess
it — somebody might experience chest pain. Now that can be really scary for people, because a lot of times when we think of chest
pain we think of things like a heart attack. But there are some things that we
can use to distinguish the type of pain that pericarditis causes compared to
say something like myocardial infarction, which is a fancy-pants name for a heart attack. So how the chest pain is typically described
in pericarditis is sharp, with a quick onset. Meaning it comes on fast and
has this sharp nature to it. And because of the inflammation
of this pericardial tissue, it also contributes to another unique
feature of the type of chest pain people experience which is it tends to improve
when people sit up and lean forward. It's also described as pleuritic. Now what in the world does pleuritic mean? Pleuritic chest pain is chest pain that's worsened with coughing or
deep breathing — specifically breathing in. And that is one way to kind of distinguish
it from other types of chest pain. Another thing that will happen if you go to
the doctor — which we typically recommend with chest pain — is they'll auscultate
your heart or listen with a stethoscope, and often hear what's called
a pericardial friction rub, which is because the inflammation on the
pericardial sac is now not reducing friction like it's supposed to, and you get this rubbing or this
specific type of heart sound with pericarditis. Now something else that'll likely happen
in this situation is a patient would get something called an EKG or an ECG,
which stands for electrocardiogram. And certain heart conditions can have
certain features that will show up on an ECG, and pericarditis is one of
those conditions that can have unique features that a clinician can possibly
recognize on that electrocardiogram. Now on top of everything else
that can occur with pericarditis there's one other thing we need to
mention that's pretty important. Some people can develop what's
called a pericardial effusion. Now remember, inside this space
there was a little bit of serous fluid to help reduce friction between
the heart and the surrounding tissue. But a pericardial effusion is when too much
fluid starts to build up in this space. You can have mild amounts, all the way up to large amounts ,which can obviously be
more serious and more severe. So how serious is pericarditis? Well luckily, most patients do just
fine and can be treated at home with time, rest, and supportive therapies. Because most of the time pericarditis is
caused by a virus or what they say is an idiopathic cause, which is a fancy way of
saying they don't really know the cause, but as long as the patient's stable and not
getting worse, they can be safely treated at home. What may cause a patient to need to
be hospitalized for this might be other conditions that are being exacerbated
by this a large pericardial effusion. So a lot of fluid buildup around the heart,
or maybe even something like a high fever. So as I teased earlier, treatment was
essentially rest with supportive therapies. Now specifically those supportive
therapies would typically be anti-inflammatories like NSAIDs, or
nonsteroidal anti-inflammatory drugs, which ibuprofen and something like Aleve — or also
known as naproxen — those fall into that category. Now some patients can't tolerate
NSAIDs, so in that case they might give them something like prednisone,
which is a steroidal anti-inflammatory. But typically one of those two drugs is going to
get paired with another drug called colchicine. Colchicine is typically used for gout —
for those of you who unfortunately get to deal with that — but colchicine
can be also used for pericarditis. And the patient will be on these
for an extended period of time. They rest, and they typically get
better with that supportive therapy. And now that we've gone over pericarditis, let's
do one more thing again just for good measure. [Jonathan makes strange noise...] Look how cool this is! It's awesome! Thank you for going on the tour of the
pericardial sac with us today everybody! Also want to thank those who donate
their bodies to science and education. This type of education would not be possible
without their amazing anatomical gift. It has helped pave the way for multiple different people to go into multiple healthcare
professions that then help the living. So thank you to all of them! Please like, subscribe, and ring the bell
so you know when our next videos will drop. We love your guys support and your comments below. So please do that because we love your
ideas and love to interact with you guys. So until next time — take care
of those pericardial sacs... I think that's all I have to say — goodbye!