Pulmonary Hypertension – Pathophysiology & Diagnosis (HTN)

By Adem Lewis / in , , , , , , , , , , , , , , , , , , , , , /

well welcome to another MedCram
lecture we’re going to talk about pulmonary hypertension treatment and
there’s actually several different types of treatments remember there are
different waho groups there’s Group 1 2 3 4 & 5
now group 1 we said was idiopathic pulmonary arterial or hypertension and
the other ones for instance the collagen vascular diseases the drugs the toxins
those sorts of things number one is where most of the work in terms of drugs
specifically for pulmonary hypertension have centered there’s also one that is
FDA approved for four which we’ll talk about
but remember why this is is because group two is almost exclusively is
exclusively due to left ventricular failure Group three has to do with lung
disease and group five is kind of a grab-bag so these already have their
treatments specifically for them one has a whole bunch which we’re going to talk
about and there is one that is indicated for for remember for is for venous
thromboembolism or chronic pulmonary hypertension or as it’s officially
called chronic thromboembolic pulmonary hypertension and that’s abbreviated c t
e p h okay so let’s talk about number one and the different types of
treatments okay so there’s some things that all
groups would do well to start and we’re going to make this as simple as possible
and explain it as clearly as possible as we normally do so because of the fact
that they get this lower extremity diuretics is something that you want to
do the other thing that you want to do if they need it is oxygen therapy and
they’ve noticed on autopsies that there are a lot of blood clots not just in
group chronic thromboembolic pulmonary but also in the other groups after many
studies anticoagulation was found to be definitely something that you want to do
in group 4 and maybe in group number one other medications that might be
beneficial is the Jaques in’ and exercise definitely beneficial so these
are ones that can go really to just about all classes let’s talk about group
one now and the different classes now before we start with the advanced
medications that some of you are familiar with we have to do something
called a vaso reactivity test and the reason why we do this is because those
who respond to the vaso reactivity test are more likely to respond to ordinary
medications like calcium channel blockers like the dihydropyridine and
diltiazem the calcium channel blockers so if they respond if that’s a positive
response calcium channel blockers if it’s negative then we go on down to the
more advanced medications so what is the base of reactivity test looking at well
there’s a number of ways you can do it you can use nitric oxide to see whether
or not the patient’s mean pulmonary artery pressure drops by 10 millimeters
of mercury the other thing that you can do is you can use equal process in all finally the other thing that you can use
is adenosine so all of these are medications that can be used to see
whether or not the patient is reactive and once again it’s considered positive
if the main pulmonary artery pressure decreases by at least 10 millimeters of
mercury and goes to less than 40 millimeters of mercury this is assuming
that the cardiac output actually gets better or it’s unchanged and as we
mentioned patients with a positive reactivity tests are ones that could
improve with calcium channel blockers those that are Nega
will not respond to calcium channel blockers so once we do this and I’ll
tell you it’s a very small percent are actually reactive most of these are
going to go into the negative category and so most of them are going to be
having to be put on advanced medications if we’re dealing with a group one so
let’s talk about those things but before we do the thing that’s going to
determine what medication they get is to determine how sick they really are and
that’s determined by a w-h-o again functional class and so there’s
functional class 1 which is the most mild and they typically don’t need
medications that can be monitored and then there’s class
– and there’s class 3 and these are where most of the medications are
actually started and then there’s class 4 which is the most severe and these are
usually given IV so the way I remember it is that class IV should be given IV
class 1 doesn’t need to be giving any medications orally and the ones in the
middle are given Pio meds and those Pio meds we’ll talk about very shortly most
of these medications haven’t been around for more than 15 years that’s how new
they are and if you’re lucky enough to have a patient who is responsive to a
Veysel reactive medication then you can just give a calcium channel blocker
which is dirt cheap and has been around for many years if on the other hand they
don’t respond and there are w-h-o class 2 or 3 then you’re going to be starting
them on some Pio meds which we’re gonna talk about right now the first category
is the prostacyclin agonists so this is like equal process and all IV which is
indicated for stage 4 IV as we talked about there’s tree procced Annelle which
can come IV sub-q or inhaled there’s Isla Pross which is comes inhaled and
then there’s these prostacyclin agonists which are not really prostacyclin x’
like celexa peg which all of these things stimulate the prostacyclin
receptor and in effect caused an increase in cyclic AM P and therefore
vaso dilation okay so those are the prostacyclin
agonists the next group are the endo feelin receptor antagonists so endo
feelin one is a hormone that basically circulates around and is extremely
potent vasoconstrictor so if we could possibly block these receptors
potentially we could get some basal dilation that’s exactly what we see
there’s two types of receptors is the a and B and so both senton and massive
Tenten is basically a drug that blocks these receptors it’s non-selective and
it seems to reduce the PA pressures it also like a lot of the other medications
improves the quality of life extends the length of time before decompensation and
increases exercise capacity one of the selective ones is amber senton so these
are the receptor field and receptor antagonists these are a list of
medications that are fda-approved for pulmonary hypertension specifically
sildenafil and Tel dalla fill the purpose of these things is to inhibit
the breakdown of these medications which basically increase the amount of nitric
oxide so there is cyclic GMP and that cyclic quantity monophosphate is broken
down by phosphodiesterase well these medications inhibit the ability of this
phosphodiesterase to break down the cmp and so these are why they’re called pde5
inhibitors and so what happens is cyclic GMP goes up which stimulates an increase
in nitric oxide and it’s nitric oxide which is a vasodilator okay so there’s a
couple of other things that also increase vasodilation and that would be
like an alpha blocker or a nitrate so you should not be on these medications
at the same time these pb5 inhibitors cause vasodilation in the pulmonary
vasculature by increasing nitric oxide and they do it specifically by
inhibiting the breakdown of cyclic GMP the last mechanism that we’re going to
look at is the guanylate cyclase direct stimulants and this riociguat is one of
the medications that is fda-approved is the medication that is FDA approved to
do this and it’s a direct stimulator of the nitric oxide receptor so it
increases nitric oxide just like the phosphodiesterase inhibitors do but they
do it in a different way and they have a dual mode of action not only do they
increase the nitric oxide receptor they also increase the sensitivity of the SGC
to endogenous nitric oxide which is a pulmonary vasodilator and so they also
directly stimulate the receptor to mimic the action of nitric oxide so this is a
little different and not only is it approved in a pH group w-h-o group
number one but it’s also approved for w-h-o group number four which remember
is the chronic thromboembolic disease so just be aware of that now all of the
medications that we’ve just talked about can be used in combination but you’ve
got to be careful make sure again that you are using these in combination after
you have done a right heart cath and made sure that they are not reactive so
you could add for instance tadalafil and amber senton you could use sildenafil
and both senton you could use both senton added to either Ypres process and
all or triple process Annelle or you could do triple process Annelle added to
either both sent in or sildenafil so there’s different ways of doing this and
this is very similar to how we increase blood pressure medication for systemic
hypertension we can also do this for pulmonary hypertension so the key points
again are that if you suspect somebody of having pulmonary hypertension make
sure that you classify them in a w-h-o group if they are group 1 or 4 there may
be medication specifically designed for these types of diseases if it is group 2
you need to get the underlying cause of the left
heart disease and treat that if it is three you have to look at the underlying
cause for the hypoxemia and treat that whether it’s lung disease or sleep apnea
for you need to anticoagulate them generally and they may need to go to
surgery where they actually have the clot removed or if that’s not feasible
they may have to consider a medication like we just talked about here and then
five is kind of the grab bag it should be looked at in terms of the other
causes so that is a very brief primer in pulmonary hypertension how it is
diagnosed how it is looked at how it is treated and and what are the medications
that are involved so thanks for joining us

4 thoughts on “Pulmonary Hypertension – Pathophysiology & Diagnosis (HTN)

  1. Thanks for watching. See part 2 of this video free: https://www.medcram.com/courses/pulmonary-hypertension-explained-clearly

  2. It may be worth mentioning that regular consuming of inorganic nitrate such as beetroot juice which is a good source of production of NO!, would play an important role in decreasing that blood pressure elevation

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