hi let's talk about the pericardium external heart features in great vessels
the pericardium is the sac which covers the heart it consists of two major layers one of which
is a bilayer so the external most part of the pericardium is the fibrous pericardium which we
can see cut and reflected laterally here deep to the fibrous pericardium is the serous pericardium
which has both a parietal and a visceral layer the parietal layer of the serous pericardium
adheres directly to the fibrous pericardium so everything that we can see as this deep
surface of the fibrous pericardium is in fact the parietal layer of the serous pericardium
the visceral layer of the serous pericardium adheres directly to the heart such that it becomes
the most superficial layer of the heart wall we can see that the visceral layer of the
serous pericardium completely covers the heart both the atria and the ventricles and deep to
this visceral layer aka the epicardium there's a variable amount of epicardial adipose tissue
this epicardial adipose tissue can be directly proportional to one's risk of cardiometabolic
disease so things like hypertension atherosclerosis diabetes insulin resistance etc
that risk increases with increasing amounts of epicardial adipose tissue now the heart itself has
sulci that serve as superficial reminders of deeper structures below one of the largest of the
sulci is the coronary sulcus which i'll outline part of here the coronary sulcus is going to
separate the atria from the ventricles so everything above the coronary sulcus
will be an atrium everything below will be a ventricle so this is going to be in line with
the the the fibroskeleton of the heart so the atrioventricular valves and the semilunar valves
in the interstitial connective tissue that holds those valves together there's also an
anterior interventricular sulcus that anterior interventricular sulcus is going to divide the
right ventricle from the left ventricle so that's where the interventricular septum is located
now with respect to this view of the heart we can see several borders so we have a right border
of the heart this right border of the heart corresponds to the right atrium we also have a
left border of the heart the left border of the heart corresponds somewhat to the left atrium
but mostly to the left ventricle there's also a superior border the superior border is going
to correspond to both the right and the left atria there's an inferior border also known as the acute
margin which is in association with both the right ventricle predominantly and a little bit of the
left ventricle and where this inferior border or acute margin meets the left border or obtuse
margin we have the apex of the heart and the apex of the heart is going to point antero
left laterally now when we think about the heart if we were to go directly down the midline
recall that about one third of the heart mass is going to be to the right of midline whereas
two thirds will be to the left of the midline now let's turn the heart around the apex is here
so that we can identify it the posterior aspect or the base of the heart which we've yet to see
very well is there this is the inferior vena cava we can see a continuation of that coronary sulcus
across there and then there's also a posterior interventricular sulcus
that's going to be superficial to the interventricular septum so here we're going to
have predominantly the left ventricle and here will be the right ventricle now there are also
several surfaces of the heart that you're going to want to know about in the anterior
view most of what we can see is going to be the anterior or sternocostal surface so that is
that structure we also have a right surface so think about this a little three-dimensionally so
here will be the right surface there is a left surface that would be
that surface there there is also a diaphragmatic surface
this is the surface which is just um above the pericardium which is fused to the diaphragm
and then finally it's rather trapezoidally shaped we have the base of the heart the
base of the heart is pointing posteriorly towards the towards the vertebral column
now there are also several great vessels that are associated with the heart great vessels are
any vessels which directly deliver blood to the heart or directly port blood away from the heart
so the great vessels that are in association with the right atrium are the superior vena cava
in the inferior vena cava so these are the vena cavae and all of the blood that they return to
the heart is part of what we would call the caval system now in terms of major arteries
we have the aorta and when it leaves the heart it's the ascending aorta and then
it's the arch of the aorta and then it's the descending aorta with both
thoracic and abdominal parts depending on whether you're in the thorax or the abdominopelvic cavity
and then there is also the pulmonary trunk and that pulmonary trunk divides into
the pulmonary arteries both right and left although those pulmonary arteries are not part
of the great vessels because they don't leave the heart directly and then finally flanking the base
of the heart we have the four pulmonary veins and this one is a little collapsed so from this
angle we could also see the inferior vena cava the superior vena cava the pulmonary trunk and
the ascending aorta going into the aortic arch thank you very much for your time