hi let's talk about the pericardium
the pericardium is a sac which surrounds and encompasses the heart
it's formed of two layers an outer rough and tumble fibrous pericardium which we can see here
and an inner delicate mesothelial membrane called the serous
pericardium now the fibrous pericardium is going to serve as an anchor point for
the heart we're going to see that it encompasses much more than the heart
it comes superiorly to surround many of the great vessels in particular the ascending aorta
and the pulmonary trunk as we can see this is reflected away inferiorly the fibrous pericardium
is fused to the diaphragm so the heart within the pericardium is going to move with ventilation
the fibrous pericardium is inelastic and you should you should feel this and demonstrate it
for yourself in the laboratory it does not stretch it's going to represent the maximum amount of
space that the heart will be able to relax into during diastole and it's also a physical barrier
to infections entering the heart it's a triple layer of collagen protein each woven at about
120 degree angle to the other layers the serous pericardium is deep to the fibrous pericardium and
as a serous membrane you might think that it has two layers and you would be correct there is a
parietal layer the parietal layer lines the wall of the cavity where something is in and a visceral
layer the visceral layer is upon the heart itself so that parietal layer adheres directly to the
fibrous pericardium so in this image here with the pericardium and sized and reflected open
everything that we can see here is this shiny surface is going to be the parietal layer of the
serous pericardium sometimes just called the parietal pericardium now the visceral layer
of the serous pericardium is also known as the epicardium it is upon the heart
so if you encounter a heart such as this the most superficial layer is that of the epicardium
and it is actually a ciliated mesothelial membrane deep to the epicardium is going to be
the epicardial sometimes called subepicardial adipose or fat it tends to be directly
proportional to cardiometabolic risk factors so the more epicardial fat an individual has
the higher the risk of different diseases such as hypertension coronary artery disease insulin
resistance and diabetes etc and here we can see some of that epicardial fat we can also see
and we'll get into this in the next session
some of the vasculature which is moving through that epicardial fat to serve the heart wall
the space between the parietal and visceral layers of the serous pericardium
is the pericardial cavity and so we can see
this here there's not much room actually in life the only thing that we really find in that
pericardial cavity is about 10 maybe 15 milliliters of ultrafiltrate
which is secreted by the visceral layer of the serous pericardium materials can
accumulate within the pericardium so if there's inflammation so pericarditis um transientate can
fill if there's injury blood can fill and that can put pressure on the heart which would be
cardiac tamponade so this is the uh the pericardium fibrous in serous layers and the
cirrus has both a parietal and a visceral layer thank you very much for your time