welcome to the second video in this
series on disorders of the
cardiovascular system where we're
looking at it from the perspective of
the various blood vessels or the various
aspects of the circulation so we've
looked at the pulmonary arteries here
taking blood from the right ventricle
through to the lung or to the lungs and
we've noticed when you might get raised
pulmonary arterial pressure in this clip
we want to consider the systemic
arteries so what disease is effect
systemic arteries well we noticed the
normal blood pressure in the systemic
arterial system is 120 over 80
millimeters of mercury 120 systolic 80
diastolic well that might be a blood
pressure that you typically find if
you're young and fit your blood pressure
may be quite a bit lower than that
that's that's acceptable right is good
so we're thinking about systemic
arteries these are the arteries that
break down and take blood to all of the
body apart from the lungs all the
systems of the body receive their blood
supply via the aorta the first two
vessels right down here that actually
leave the air your tour of the coronary
arteries the right and left coronary
artery taking blood to the myocardium
itself so we noticed the normal blood
pressure there and there's a common
condition called hypertension
hypo of course is high tension means
pressure so blood pressure can be too
high now this can be a primary also
called essential hypertension or it can
be secondary now this is the same with
quite a few diseases a secondary
condition is one which is caused by
something else whereas a primary
condition is one was just arises without
apparent cause so for example secondary
hypertension is often caused by renal
problems the kidney is very closely
involved in control of blood pressure
problems in the kidney can give rise to
hypertension but other times you get
your blood pressure checked and it's a
bit high and that can maintain firm
forever if you if you develop it primary
hypertension doesn't seem to be caused
by any underlying pathology it seems to
start with the blood pressure itself so
it's also called essential hypertension
both of these can be dangerous because
high blood pressure ism is not a good
thing to have this one's probably most
cases probably because because the
kidney produces too much of renin and as
you might know from other learning that
affects the renin-angiotensin system
which we do deal with in in other videos
so it's very important for you to detect
hypertension by checking the blood
pressure it's important to remember that
the main clinical feature of
hypertension is that there are no
clinical features of hypertension the
most important clinical feature of
hypertension is that there isn't any we
detect it by taking the blood pressure
and that's because blood pressure is
also regulated through
a wide variety of pressures so with a
blood pressure of 90 or a blood pressure
on 160 the amount of blood going to your
brain for example should be auto and
regulated so very often people are
hypertensive but don't feel any don't
feel any adverse effects from that we
have to check it so taking blood
pressure is an essential part of every
physical assessment it has to be now if
the blood pressure is raised
we've got effective medications that can
treat it we've got a range of
medications that can treat it
angiotensin converting enzyme inhibitors
calcium channel blockers even beta
blockers even diuretics we've got a wide
range of medication and we've got
well-established protocols for treating
hypertension and we can usually manage
to bring the blood pressure down to
highly acceptable levels but if we don't
if we don't the problem is the
hypertension causes complications there
are complications associated with
hypertension and these can develop
silently because the patient may not be
aware there's anything wrong with them
now the hypertension can occur on its
own or it can occur with obesity or it
can occur with the metabolic syndrome
where it can be associated with dis
lipedema hyperglycemia particularly in
patients with abdominal obesity but it
can they can just present on its own
there's ejection etic component
sometimes but but again not necessarily
and there are complications one of the
complications is atheroma develops in
the blood vessels the disease process of
atherosclerosis
there can be a thorough sclerosis now
if the blood pressure here is high
what's that going to do to the right the
left ventricular workload if the
pressure in the systemic arteries is
high you can see that means it's going
to be harder for the left ventricle to
contract to pump the blood out against
the increased outflow resistance
there'll be an increased after load it
was the same with the pulmonary arteries
when there was pulmonary arterial
hypertension that increased right
ventricular workload when this systemic
arterial hypertension the left ventricle
has to pump harder to pump the blood
into the systemic arteries now for a
while it can do that there can be
enlargement of the left ventricular
myocardium left ventricular hypertrophy
now this conditions are hypertrophy
because when you exercise a muscle the
muscle will get bigger like if you go to
the gym and start working out your
muscles will get bigger but that's
because the individual cells get larger
it's a hypertrophy there's not an
increase in the number of cells and
overtime but to begin with the left
ventricular hypertrophy or compensate
but then over time the left ventricular
hypertrophy will lead to left
ventricular failure so we'll get heart
failure starter's left ventricular
failure
so that will lead to heart failure and
if the left ventricle fails if the left
ventricle is not pumping the blood out
properly then that will mean that the
some blood left in the left ventricle at
the end of systole that's going to make
it harder for the blood to get from the
left atrium into the left ventricle that
means the blood is going to find it
harder to get from the pulmonary veins
into the left atrium there's going to be
a damming bag so because the blood is
not effectively pumped out of here
because the left ventricle is failing
the blood will down back to here or down
back to here so you're going to get a
pulmonary venous hypertension and that
can result in pulmonary edema so the
left ventricular failure can result in
pulmonary edema just the same way as the
right ventricular failure means the
blood is going to down back and that can
cause pulmonary edema if you follow the
circulation back this time you follow
the path of the congestion and left
ventricular failure does not have a good
prognosis is a very serious condition
the Khitan is like a constant blood
pressure so there can be renal
complications as a result of
hypertension and another big risk is is
stroke cerebral vascular
cerebral vascular accident one of the
primary causes of that is is
hypertension so very important that the
pressure in the systemic arteries does
not become too high so the person does
not become hypertensive and therefore
will not suffer the complications of
which we've just sketched out a few here
now if you recognize the hypertension
and treat it you can prevent these
complications and other complications
there's many more complications dementia
for example is more common so you can
prevent this as long as you detect it so
that is one condition affecting the
systemic arteries the next condition on
the next video clip we want to look at
also affecting the systemic arteries is
this disease process of atherosclerosis
which is still one of the major causes
of premature death and suffering in the
Western world and unfortunately is
becoming more and more common in
developed countries as well