112. Guidelines Series: Pulmonary Hypertension – Definitions, Screening, and Diagnosis

Today we’re kicking off another segment in our Guidelines Series, and doing a deep dive into the 2022 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. Over a series of episodes we’ll talk about the most recent updates … Continue reading →

Episode Transcript

(00:16):
Hey, everybody. Welcome back to poem peeps. We
are excited to be back again today with
another episode and joined by our two amazing
associate fellow editors at Rapala suit and, and
Tom D V Antonio. And, very excited to
be back with another episode on a topic
that is near and dear to my heart.
So
really looking forward to this. Monty, how are

(00:37):
you? Hey, Farf. I'm doing well. Very excited
to be back with this crew.
And I know I was actually pulling up
our infographic for the asthma guideline series that
Rupali and Tom made and was referencing it
the other day. I continue to use this,
so hopefully those listening today will find these
series very helpful and relevant to your day

(00:57):
to day practice.
Yeah, absolutely. And today we're gonna be going
forward with our guideline series. We're gonna be
moving on to a new topic, which is
pulmonary hypertension. My favorite topic,
pulmonary hypertension is super interesting and fascinating field
spans pulmonary and cardiology, depending on where you
are, but very important for all pulmonologists to
be extremely familiar with the guidelines.

(01:19):
And interestingly,
there are multiple organizations
that play a role in how we think
about pulmonary hypertension.
And so whoever has the most recent guidelines
usually becomes what we're functioning on. So for
a long time, the world symposium on pulmonary
hypertension had the most recent guidelines. We were
following, but more recently in 2022,

(01:40):
the European society of cardiology and the European
respiratory society released updated guidelines that had some
changes and have influenced how we think about
and practice our pulmonary hypertension diagnosis and treatment.
So we are gonna start today diving into
those guidelines with a foundational episode, where we're
gonna talk about symptoms, screening, and diagnostics.

(02:01):
Some of these things will be similar to
the old guidelines, but we're gonna review all
of it. And then we'll try to make
a good point of highlighting
what has changed and what has developed and
how we should rethink
about some of these topics. Awesome, Farfana. I
know you love pulmonary hypertension. I think that
more than anyone I know, it's just so
exciting and such a great topic to cover.

(02:21):
I think for a lot of trainees and
for fellows and even some attendings, pulmonary hypertension
can be a very scary topic, but, our
hope today is to walk through it, give
everyone a great foundation.
Obviously we can't cover everything in pH in
one episode, but give you a good framework
to start thinking about your patients where you
suspect it. Our roadmap today of what we're

(02:41):
gonna cover, we're gonna try to cover seven
broad topics within pH to give you this
great framework. The first one is gonna be
when to suspect pulmonary hypertension.
Right? This is going to be recognizing clues
and risk factors in patients that you're caring
for. The second part of our roadmap today
is going to be the world health organization
classifications.

(03:02):
So understanding the five groups of pH and
some of the baseline pathophysiology
associated with each group.
Our third part on the road map is
gonna be interpreting echocardiography,
and I know we'll go through how to
assess the probability of pH based on echo
findings.
Our fourth stop is gonna be noninvasive testing.

(03:22):
So which test to order, when to order
them, and what they're gonna be telling you.
The fifth stop is gonna be right heart
catheterization.
Then we'll go through a little bit in
this, and I'm sure we'll interpret some numbers
and give you some values to keep mind
of. And this is gonna be when is
a right heart cath indicated,
how it's performed, and how to interpret the
results.

(03:42):
The sixth part will be vasoreactivity
testing. Again, this is gonna be can be
part of a right heart cath diagnostic test.
We'll talk about who qualifies, how's it how
it's done, and what a positive result means.
And then the last stop of the road
map today is gonna be screening high risk
populations.
So this can be how to approach patients
with conditions such as connective tissue disease,

(04:02):
HIV, or portal hypertension that you should be
aware of.
So excited to go through all of this
together with this crew.
Yeah. Thanks, Monty, for the road map. And
I think that
looking forward, we will, after talking about these
conditions, talk some more specifically about other diagnostics.
We'll talk about condition specific conditions, and then
we'll really dive into treatment broken down by

(04:24):
the most common conditions and how to think
about that. So a lot of great episodes
coming in our future.
As I already said, we're thrilled to be
back with Roopali and Tom. Roopali, you were
just jet setting for multiple weeks. I'm glad
that you landed safely and are back on
Palm Beach today. Thanks, Dave. Happy to be
back. I lost my voice a little bit,
but excited to be here with this crew
and,
ready to get this started. And this episode

(04:45):
is such a great starting point for pulmonary
hypertension.
Pulmonary hypertension can be a very subtle diagnosis
at times, and recognizing it early can really
change outcomes for patients. So I'm really excited
for this specific episode today.
Awesome. And, Tom, Abe, it's always great to
have you joining us as well, even if
you've only been just stuck in Baltimore for
the past couple weeks. Yeah. I've been mostly

(05:06):
hanging out in Baltimore recently. I did not
I have not been, traveled around like RuPauli
has, but, like, excited to be back with
everyone. And from a fellow standpoint, I think
having a clear diagnostic
framework
for how to approach these patients, is a
really helpful thing to have in your back
pocket when you're seeing someone in clinic or
in the hospital with unexplained dyspnea.
Yeah, absolutely.

(05:27):
So just our standard disclosure, this episode is
not meant for specific medical advice, but for
medical education
and the opinions and that we reflect or
the opinions that we share may not reflect
those of our respective employees.
Great. So fantastic to get started and to
help ground this discussion. I know we always
think it's really important to
provide any teaching and pair that with a

(05:50):
actual patient case because we always have to
bring it back to the patient and bring
it back to the bedside. But we're probably
hoping you can start us off.
Definitely.
I'll tell you about a patient I saw
in clinic. This is a 58 year old
woman with limited systemic sclerosis that she'd had
for years who presented to clinic and was
referred for progressive dyspnea over the past ten
months. She used to be able to walk

(06:11):
several blocks without any problems at all, but
now she gets short of breath when she
just does basic tasks around the house,
including getting up to just cook in our
kitchen and putting her clothes on in the
morning.
She had no obvious Frenkel disease on CT,
including any evidence of ILD or any obstructive
lung disease. She had no symptoms of chest
pain, nor orthopnea,
no PND, but just some vague slow developing

(06:33):
shortness of breath.
This is a classic setup where pulmonary hypertension
might fly under the radar. So let's try
and keep her case in mind as we
go through the framework today.
Thanks, Rapala. That's a great example to kick
us off with. She, as we'll talk about,
is one of those patients who has a
risk factor for developing pulmonary hypertension in her
systemic sclerosis, and that slow insidious unexplained decline

(06:56):
is often how it presents.
Yeah. Thanks so much, Tom. And thanks, Repali,
for getting us started with that case. And
I think you write a very common presentation
that fellows may be seen
in their continuity clinic or residents taking care
of a patient. This may be someone who's
coming in their clinic as well or being
admitted. So very common presentation, and you mentioned

(07:18):
some great things already
to probably help us thinking. As we said,
this progressive decline
over the last eight to ten months, dyspnea
now on exertion,
fairly normal
parenchyma on CT images. But I know there's
so much more that we would wanna delve
into, getting a little bit more history as
well as exam and some further diagnostics.
But we're probably just thinking about pulmonary hypertension

(07:40):
in general. When should we actually suspect it?
That's a great question, Monty. And as we
mentioned, the most common presenting symptom is often
just dyspnea and especially
dyspnea on exertion specifically.
But it is a little bit nonspecific that
often pulmonary hypertension is not considered until later.
Other associated symptoms can include fatigue, lightheadedness,

(08:01):
exertional chest pain, or syncope,
particularly as right heart dysfunction develops.
These symptoms, specifically
the insidious onset of dizzy on exertion, had
me thinking about my patient.
As you mentioned, physical exam is important part
of what we do. In later stages of
the disease, you can also start to see
other signs of right heart failure, like peripheral
edema, elevated JVSP, specifically thinking about evidence of

(08:24):
tricuspid regurgitation
on exam. You can look for exaggerated V
waves on exam, hepatomegaly, and ascites. My patient
did have some lower extremity edema as well
as some V waves on exam of her
neck, which had me thinking about this particular
condition.
Yeah. Those are all great things and things
that I'm thinking about when I'm suspecting

(08:44):
pH. And we'll talk a little bit more
about the other conditions that really raise red
flags. A big red flag for me, and
a lot of times when people end up
at my clinic is that the symptoms that
they're having are just not aligning with our
classic objective data in in our pulmonary clinic.
So they might have a relatively normal CAT
scan or at least the parenchyma appears relatively

(09:05):
normal, but they're having the severe dyspnea on
exertion. They also might have normal spirometry
because we often don't see the defects of
pulmonary hypertension on just a basic spirometry FEV1
FVC, but their dyspnea is getting worse. And
we'll talk about some of the other features
that we can look for to give us
a hint about pulmonary hypertension.
So these disconnects always put pH on my

(09:26):
radar or at least someone I wanna think
about pulmonary vascular disease.
And I'll just add the importance to this.
So one is that we know there is
a persistent
delay in diagnosis for pulmonary hypertension.
So this has gone down over time, but
still, depending on the sources you look at,
somewhere between twelve to twenty four months from

(09:46):
the time that symptoms onset and the patient's
really experiencing it, and we get this diagnosis
of pulmonary vascular disease. And then there's often
a delay after that, between the diagnosis and
treatment. And this is profound impact for our
patients. Any delay that they have can increase
their mortality because this is a pretty morbid
condition overall, depending on where you look or
someone might say that a delay of two

(10:07):
years would increase your mortality by about ten
percent over the next five years, a delay
of five years increase mortality by twenty five
percent. These are real numbers that we care
about. And so some of the changes in
the guidelines and some of them emphasizing
this high clinical suspicion have really been focused
on trying to make these diagnoses earlier and
especially in patients with pulmonary arterial hypertension. So

(10:30):
we'll talk about the different subtypes, but this
is the group that can often go missed.
It might be a little bit younger patients.
They might not have classic other findings. And
if we can make this diagnosis early, we
can really improve their disease course over time.
But if we delay this diagnosis, it can
have profound impacts for them.
Yeah. They're so important to think about. And

(10:51):
thank you for mentioning that. And I think
one another important thing to think about when
we think about pulmonary hypertension as a possible
diagnosis,
there are really two important portions of the
diagnostic workup. And the first is really confirming
the diagnosis. And I know we're gonna go
through all of this, but I think a
teaching point for those listening today, right, I
know sometimes people will put in a one
liner or put, like, in an assessment and

(11:12):
plan a patient has pulmonary hypertension,
but they're writing that based off of the
patient potentially having an enlarged pulmonary artery on
CT finding, which is not a diagnostic
test and or suspecting on echo that the
patient might have pulmonary hypertension. And we're gonna
walk through all of this together, but, really,
what you need to confirm the diagnosis is

(11:33):
actually a right heart cath, which we'll we'll
also also talk a little bit later today.
But I think that's really important. When you're
saying someone has pulmonary hypertension, you're gonna want
the evidence behind it with that right heart
cath and the diagnostic and the numbers. I
think all four of us have the opportunity
to work with Paul Hassoun, and I remember
as a fellow
talking about a patient with pulmonary hypertension. He's,
yes. But what tell me why. What's the

(11:54):
mean arterial pressure? What are the WOODS units?
And he's, Christina, what is a cardiac index?
So all of these things are gonna be
needed that we can't get alone from just
looking at imaging and looking at echo. So
the first, how do we walk through confirming
the diagnosis?
And the second is to really think about
why the patient may have pulmonary hypertension.
And I think we'll have to focus a

(12:14):
bit on the etiologies,
and to help us think about why a
patient may have this and really determining pretest
probability of pH.
So, Tom, I know one of the stops
of the road map, I said, we're gonna
talk about the five etiologies
that are classified by the World Health Organization,
and I'm hoping that you can walk us
through those now.
Sure. I would love to. As Christina was

(12:35):
saying, we tend to group pulmonary hypertension
into five buckets,
group one through five. I feel like this
is where a lot of us get exposed
to this in medical school, and the prototypical
patient we learn about in medical school is
the person that falls into group one. That's
the young woman with exertional dyspnea who has
pulmonary hypertension, but there's a whole lot more

(12:56):
conditions that can lead to pulmonary hypertension and
a lot of different phenotypes and pathophysiologies.
So when you get to group one pulmonary
hypertension, this is where we're thinking about PAH,
pulmonary arterial hypertension.
And there's a lot of things that can
cause this. Your classic teaching is idiopathic,
IPAH.

(13:17):
But there's also many heritable forms of PAH.
And as our testing abilities and understanding of
molecular diagnostics gets better, we're uncovering more and
more mutations that can predispose someone to PAH.
This is also where you'll find folks with
drug induced pulmonary hypertension, things like dasatinib,

(13:37):
connective tissue disease associated
PAH, such as scleroderma, systemic sclerosis,
portal pulmonary hypertension, HIV,
HHT,
hereditary hemorrhagic telangiectasia.
This is also where you put patients who
have PAH secondary to congenital heart disease or
shunts. This this it'll lead to increased flow

(13:57):
through the pulmonary circulation
and pulmonary hypertension.
And then lastly, you get some much more
rare but really important things to consider,
such as PVOD
and pulmonary capillary hemangiomaticosis,
PCH.
Now moving on to group two, which is
where you actually find most causes of pulmonary

(14:19):
hypertension.
These are pulmonary hypertension cases related to left
sided heart disease.
So folks with left sided
heart failure,
particularly things like HFpEF, are really important.
Group three, this is where you find pulmonary
hypertension
related to chronic lung diseases,
hoxia,

(14:40):
things like COPD,
interstitial lung diseases,
and then obesity hypoventilation
syndromes in particular.
Group four, these are patients with chronic thromboembolic
pulmonary hypertension, also called CTEF.
And then lastly, group five,
these are
conditions that lead the pulmonary hypertension

(15:02):
through a multifactorial
pathophysiology
or some unclear mechanism.
This is where you find conditions such as
sarcoidosis,
myeloproliferative disorders,
chronic kidney disease,
and sickle cell disease.
This classification is really helpful in
thinking about how you're going to proceed with
your workup. In our patient, for example,

(15:24):
their systemic sclerosis
raises concern for group one PAH
or group three PAH, if they were to
have some ILD, which many patients do, but
we need data to confirm.
And, Tom, I'm just gonna hop in and
add for this. One of the thing reason
that these categories are so important is
or the way the categories are made is

(15:45):
one is based on path histopathologic
diagnosis. Like what changes do they have in
the pulmonary vascular system?
And that can get a little murky. People
with group two and group three disease can
start developing
some of the changes that we see
in patients with group one, intimal hyperplasia, plexiform
bleusias, things that we see on histopathology.

(16:06):
But they also can have foreign potential without
those driven by their other disease. So this
is where we get, like, a lot of
overlap between them. But in addition to the
histopathologic,
a lot of this has to do with
treatment. How
quickly do we have to treat and what
treatments are gonna be most beneficial. And so
these categorizations
really help us in both that prognostication,

(16:26):
diagnostics,
prognostication,
and then ultimately in treatment, which we'll talk
about in further episodes.
Thanks, Tom and Dave. That's such a great
framework and a way for us to think
about ILD. As you mentioned, as soon as
I started thinking about my patient and ILD,
I knew she had stethomatosis, so I was
thinking about group one versus group three pulmonary
hypertension

(16:47):
as a possibility. And like David mentioned, sometimes
it's difficult to parse out how to group
these patients because sometimes their conditions can help
them fall into various categories so they can
fall into multiple categories. Then it's important for
us to think about treatment as alliance with
that. For example, stenosis
can be group one, group three, and we
know sick something like sickle cell disease can
really span all other groups and that can

(17:07):
be difficult sometimes.
But once we are suspicious for pulmonary hypertension,
we really wanna further clarify our pretest probability
of this disease.
So this includes some of the things that
we have discussed, including a physical exam where
we look for signs of RV failure or
RV strain.
We talked about peripheral edema, validated JVP,
evidence of tricuspid regurgitation with exaggerated p waves,

(17:29):
pulsatile liver, pronounced p two and RB HEED.
However, sometimes these can be absent in early
disease, and so it's also important to to
think about other tests we might want when
this patient is presenting to us in the
clinical setting. So other things that we can
look for that could clue us into this
etiology
may be other findings on physical exams. As
Tom mentioned, there are a lot of systemic
conditions that can often be associated with pulmonary

(17:51):
hypertension.
For example, if the patient has hematologic tasias,
we can maybe think about one of the
connective tissue diseases, scleroderma,
natriures Tios mentioned. And if they have clavine,
we may worry about group
three related sort of hypoxemia
and other diseases.
But beyond the physical exam, there are some
initial tests that the guidelines recommend that we
should be ordering for our patients release have

(18:11):
a high pretest probability of pulmonary hypertension.
So the first is green natriuretic peptide or
NT proBNP,
and this is specifically to look for evidence
of RV strains. Just as the left ventricle
gets strained, the right ventricle can be strained
and stretched in the same way and ordering
this test. And if it's elevated, it can
be from baseline, it can be helpful
in helping

(18:32):
to increase the pretax probability of this disease
and make us more sure on our diagnosis.
Second thing that we should do with our
patients in clinic is arresting oxygen saturation.
But more importantly, as I mentioned, it's important
to pair this with ambulatory saturations
as pulmonary hypertension is much more evident on
exertion because exercise
increases
the demand on the cardiopulmonary

(18:53):
system, and it usually will unmask that abnormal
pulmonary vasculature response that could be hidden at
rest. So very important to get ambulatory SAS
and to even consider a six minute walk
test because that really helps to provide a
baseline on as to functional capacity for our
patients, which is important because a lot of
our treatment parameters actually,
focus around that as well. And last thing
I'll mention that can be easily done, especially

(19:16):
in the inpatient out sitting setting is a
chest x-ray and EKG. These are lower yield
generally, but sometimes you can see signs of
RV enlargement, right axis deviation.
And then most importantly,
number one, most important screening test to order
when we have a high pretest probability of
pulmonary hypertension
is a trans echogram because we get a
lot of rich information.

(19:36):
And I'm hoping, Dave, you can focus us
in on the transerotic
Jurassic echogram or the TTE
a little bit more.
Yeah. Absolutely. Before I dive into echocardiogram,
which is certainly one of the my favorite
topics, I just can't stress enough how much
NT proBNP
is valuable in our clinic, pulmonary hyperdenture clinic.
The one I'll say, NT proBNP is better

(19:58):
than BNP, if you can get it. It
has a little bit better sensitivity in mild
to moderate heart failure.
But for our patients with RV remodeling and
RV strain and then sometimes fluid overload,
Nd ProEMT is just an enormously helpful biomarker.
We even trust it I feel like you
I won't say more than in left heart
disease because they also use it a lot.
But I feel like a lot of times

(20:19):
we're qualifying Nd ProEMT is the patient's obese,
maybe it's lower. For our patients, we are
aiming to have this normalized over time and
it has enormous prognostic value and it's helpful
in somewhat in the diagnosis as well. Someone
has a normal one, a much more reassured
about their RB remodeling.
So just a really helpful test.
But let's go back and focus on the
echocardiogram for a moment.

(20:40):
This is the number one way that patients
get referred to a pulmonary hypertension clinic or
get pulmonary hypertension shoved into their one liner
is that they have an echocardiogram.
It's a good screening test. And we see
evidence of pulmonary hypertension,
but what is that when people are looking
at evidence of pulmonary hypertension on echocardiogram,
what are they looking at? And this, these

(21:01):
guidelines, the ESC ERS guidelines have one of
the best figures that I've ever seen in
this, in looking at how we should think
about reading echocardiogram and the echocardiographic
features
of RV dysfunction or pulmonary hypertension. And we'll
share those images along with this episode.
So the guidelines to find pH probability
on echo with the first step, looking at

(21:23):
the peak tricuspid regurgitant velocity,
and then looking at presence of other signs
of pulmonary hypertension.
So when we're looking at the peak tricuspid
regurgitant velocity,
the first thing to know is that
the presence and severity of TR
while linked to the peak velocity
is not synonymous.
So just because a patient has severe TR

(21:45):
or moderate TR doesn't mean they have a
high peak tricuspid regurgitated velocity.
They often go hand in hand, but a
patient could have a primary valvular disease and
not have have pulmonary hypertension, but have raging
tricuspid regurgitation.
You could also have a patient who they
just can't really get a tricuspid jet. They
don't see a lot of tricuspid regurgitation.

(22:07):
But, and that can be a little bit
reassuring, but it does not rule out pulmonary
hypertension because what we're really using this peak
speed as is an estimate of our pulmonary
artery systolic pressure. So just important to know
that they're linked, but not synonymous.
So when they're doing this, they're trying to
get a good envelope of the tricuspid regurgitation
and then use some of their echo assessment

(22:28):
tools to look at
peak tricuspid regurgitant.
So when we think about the risk factors
for pH and screening and deciding based on
our echocardiogram
who should go on to have a right
heart cath, We think of this in really
three categories.
So the first is low probability. Someone whose
tricuspid regurgitant velocity is less than 2.8
meters per second, who has no other signs

(22:50):
of RV dysfunction and who had a relatively
low pretest probability for pH. We can be
really reassured. This is pretty low probability that
they have pulmonary hypertension.
For patients whose peak tricuspid regurgitant velocity is
between two point nine and three point four
meters per second,
we start to get a little bit more
concerned. This is intermediate risk of pulmonary hypertension.

(23:11):
So the things that will then move me
from seeing this on a cath to doing
seeing this on an echo to doing a
right heart cath is one, how high was
my pretax probability? Is this a scleroderma
patient where I'm really concerned? Is there NT
proBNP
1,500 where I'm really concerned that they might
have this? If if that's the case, just
that 2.9 to 3.4 will be enough alone

(23:32):
to move me towards a catheterization.
Well, if my pretense probability is low, but
I see this value. And then I see
some other suggested signs on echocardiogram
that they might have RV dysfunction or pulmonary
hypertension, that will also move me down the
algorithm to thinking about right heart catheterization.
And then finally we have the high risk
someone whose peak tricuspid regurgitant velocity is 3.4

(23:54):
meters per second. For this, there are my
antenna are up. I'm likely gonna do further
investigation. If I think it's gonna impact their
treatment
over time, I will also still look for
additional signs of RV dysfunction or pulmonary hypertension,
but this makes me a lot more concerned.
So what does that velocity
translate into? Because most of the time people

(24:15):
don't reference that. What they reference is an
estimated pressure that they get.
So it's important to know how your echo
lab is doing this. So are they estimating
RV systolic pressure or PA systolic pressure? And
what are they using to calculate that? So
the standard is that we're estimating our pulmonary
artery systolic pressure, which is that TR velocity

(24:36):
squared
times four. And so that is giving us
a number that's either in that 29 to
70 range, depending on severity, right. Getting us
for a millimeters of mercury, trying to have
an assessment of this. And then it's important
to know if your echo lab is adding
right atrial pressure to that or not. And
so the echo labs might use different techniques

(24:56):
to estimate right atrial pressure. It's usually based
on IVC dilation and collapsibility.
And they're usually very broad buckets. Like the
IVC is less than two, less than two
centimeters and collapsible. So RA pressure is zero
to five. It's dilated, but collapsible. So it's
five to 10. Or it's dilated and not
collapsible. RA pressure is 10 to 15 or

(25:17):
greater.
And so you when you're reading those reports,
just helpful to know what they report. But
the standard is they're saying estimated PSP,
TR velocity squared times four.
And then it is also helpful to know
what they categorize as mild, moderate, or severe
elevation. And so this varies based on the
literature that you look at. Generally,

(25:38):
normal is less than a predicted PSP of
29 millimeters
of mercury. And that corresponds with that 2.8
meter per septum. So if we're less than
that, we have a low probability of pulmonary
hypertension.
Mild might be 30 to 40, moderate 40
to 50, and severe 50 and above. Some
people are a little bit less conservative. They

(25:58):
might say my or moderate is 45 to
60 and severe is greater than 60. But
the important thing is not what they say
it is. It's not mild, moderate, severe. It
is looking at that peak tricuspid regurgitant velocity,
that estimated PASP, and then using that for
this algorithm that these guidelines defined.
So I referenced that once we have this

(26:20):
TR velocity, we're in our low intermediate or
high probability group. This is of course influenced
by our pretest probability by some of the
conditions we already mentioned and some of the
other tests that you talked about, Roopali.
But then we wanna look at the echo
and for other signs of pulmonary hypertension.
And again, I think that the guidelines give
us a really good image to summarize these.

(26:40):
And so we'll share that. But the in
general, what we're looking for
is RV enlargement or dysfunction. So this can
either be a qualitative assessment. The echo reader
says, hey, this RV is a little dilated
or the free wall has some moderate mild
or moderate dysfunction.
And then we also have some metrics that
can help us with this. The TAPSI method
the metric was the tricuspid

(27:02):
annular pulmonary systolic excursion.
Basically, how much longitudinal
movement does the RV have measured by how
the where the tricuspid valve annulus moves up
and down as it squeezes
can help us with the dysfunction.
The RVS prime, which is a similar metric,
but looking at the speed of that movement
can be helpful. And then the RV basal

(27:24):
diameter, which is giving us a metric of
dilation. So what we really care about and
the one I follow in the pulmonary hypertension
clinic is RV size and dysfunction. And so
I'm trying to get metrics to measure both
of those.
Other signs that someone might have RV right
sided overload or pulmonary hypertension, atrial enlargement. We
usually looked at it on a four chamber
view.

(27:44):
Septal flattening. So we go to the parasternal
short and we try to see when the
RV fills and squeezes. Does it flatten
and impinge into the LV? And we get
a different based on when this occurs in
the cardiac cycle, we get some different understanding
of their RV. So if the RV the
septum is only flattening when the RV squeezes

(28:05):
in systole,
this is really pressure overload. We worry that
the patient has pulmonary hypertension.
The RV has had to become a little
bit of hypertrophied and dysfunctional.
When it squeezes, it generates high pressures and
impinges into the LV.
If the RV, if that septum is shifted
also in diastole,
we think of that more as a volume

(28:25):
problem. So when the RV is getting filled,
we have elevated RV filling pressures and that's
also squeezing into the LV. And so that
might be volume pressure overload. So we look
for those metrics.
We look for a dilated pulmonary artery, and
then we look for pericardial fusion, very bad
sign in our patients because it may indicate
that they have elevated chronically elevated filling pressures.

(28:47):
And so if we see one of those
signs of RV dysfunction or pulmonary hypertension, there
are some others as well, along with an
intermediate risk estimation of their pulmonary artery pressure
on echo. We get much more concerned. We're
gonna say we probably need further testing in
this patient.
Thanks, Dave. That was extremely helpful. And, again,
just as you mentioned, a TTE is a

(29:09):
good initial screening test. It's not diagnostic of
PH, but it does highly suggest it, and
it really helps us refine our pretest probability
for pulmonary hypertension
based on all the parameters you mentioned. And
I also like to think about it as
a helpful tool to use to follow patients
with pulmonary hypertension because right as you mentioned,
it's a helpful first reading tool for us
to get an assessment of where in that

(29:29):
mild intermediate high probability category does our patient
fall. But then if we do start treatments
over time, we can follow some of these
parameters.
One other thing I wanted to mention is
that the TTE
specifically,
we get all of these different parameters from
it, and then we are looking for pulmonary
hypertension based on that TR jet velocity.
But, also, we're looking not just for that

(29:49):
pulmonary hypertension piece, but for how the RV
is functioning.
So those things, I like to separate them
a little bit because I also wanna know
how much the RV is compensated
in certain patient and how aggressive we may
need to be as we start different treatments
and how aggressive we need to be in
treating that patient based on some of these
screening parameters. So with that framework in mind,
I just wanna share what my patient's TTE
revealed. Her TTE showed a TR velocity. They

(30:12):
were able to get a good JET at
3.1
meters per second. She had some mild right
atrial enlargement, which puts her, based on that
reference image that Dave mentioned in the guidelines,
in the intermediate
probability group,
based on those guidelines. So other echo signs
that she had on her TTE included a
PSP, which again, as we mentioned, is a
back calculated value using that jet velocity,

(30:35):
as well as the RA size around 45.
She had moderate RV enlargement, just qualitatively
called on the echo. And then she had
a TAPC or tricuspid annular planar systolic excursion,
as David explained to us, at 1.6, which
is below a cutoff of sort of 1.7
that we often think about in in what
patients how their RV is functioning.

(30:56):
And given her exam and some mild evidence
of volume overload, I wanted to start addressing
some of these initial
issues that she was having, specifically thinking about,
did she need some volume optimization with diuretics?
But, David, looks like you might have something
to add. No. I just wanted to say
thank you for correcting my acronym. You think
you could appropriately said tricuspid annulus plain or
plainer

(31:16):
insertion. I think I misspoke. It said pulmonary.
I always have lungs on the mind. Just
pointing that out for our listeners.
We all always have lungs on our minds,
which is good in our field. But for
my patient specifically, I told her that I
think that you may have this condition we
call pulmonary hypertension. I see some evidence that
the right side of your heart may be

(31:36):
struggling to keep up with some of the
demands and that some of that fluid is
backing up. And so let's start you on
this these drugs to try and get some
of that fluid off and optimize the right
side of your heart. But, Monty, what other
things should I be thinking about in terms
of workup? And maybe just more broadly thinking
maybe in this patient specific context, but for
other patients that may or may not have
the risk factors that she had, how should

(31:57):
we be thinking about other tests and grouping
those patients appropriately?
Thanks so much, Your Poly. Yeah. Right? So
think about a patient who you have a
high pretest probability for. In addition to pursuing
the right heart cath, as we mentioned, you're
gonna wanna understand the why. We need to
pursue a targeted noninvasive
testing in parallel.
Right? So thinking about potentially patients with connective

(32:19):
tissue disease, you're gonna wanna send off serologies,
AMA, rheumatoid factor,
potentially ANCA based off history and physical exam.
Things that you should be having on your
differential are gonna include lupus, vasculitis,
scleroderma,
mixed connective tissue disease,
and potentially rheumatoid arthritis.
And other noninvasive

(32:39):
diagnostics to consider are gonna be pulmonary function
test.
Specifically,
I would get a full set, so including
spirometry,
lung volumes, as well as DLCO,
diffusing capacity.
These are gonna be helpful in almost every
patient.
Like, teaching Pearl, I know some of you
have may have heard about, you know, if
you do have an isolated low DLCO,
but normal spirometry and normal lung volumes, that

(33:02):
could be a window into underlying pulmonary vascular
disease.
Other imaging diagnostics are gonna be a b
h scan.
This is gonna be best screening test for
CTEP.
High resolution CT chest. This is gonna help
us look for any underlying parenchymal disease,
specifically if we have a high suspicion for
interstitial lung disease. And then we can't forget

(33:24):
about, our overnight oximetry, especially if OSA
or nocturnal hypoxemia
is suspected.
Right. So this is really our chance to
figure out the likely
WHO group.
However, right heart cath is the gold standard
as we've talked about today, and we'll continue
to talk about throughout this episode for confirming
pulmonary hypertension.
It'll help us determine if it's pre versus

(33:45):
post capillary
and really guide treatment.
So when do we need to do that?
If the echo shows intermediate or high probability
of pulmonary hypertension,
the noninvasive workup supports pulmonary hypertension,
and if you're considering PAH specific therapies.
For for any other thoughts that you have?
I think one question that comes up in
pH clinic a lot, especially from fellows is

(34:07):
when are we ordering all of these other
tests to look for etiology of pulmonary hypertension?
And I think it depends
when I have a patient who I'm really
not sure if they have it, or if
I'm like really a 190%
sure that this is gonna be chronic ILD
or ho ho ho ho hypertension from heart
failure.
That's causing it. I'll wait on some of

(34:28):
these tests and get the right heart cath
and then decide what I need to screen
for. But a patient like this, who I
have a really high probability
of pulmonary arterial hypertension,
I really wanna do the full workup right
away. At some point, we're gonna have to
call this group one PH, which is likely
is gonna be if it if she does
end up having it with SIRoderma. And so
I just want all these tests to make

(34:49):
sure there's nothing else I'm missing, that they
don't have a group four component, that they
don't have some other component that I really
gonna need to optimize.
So some of it has depends on your
pretest probability. But for this patient, I would
plan on the right heart path and then
start gathering this battery of tests right away.
And then, Dave, I'll just add that in

(35:09):
my patient's case, we did pursue a lot
of the work that Monty mentioned. When we
did her PFTs, her FEC was preserved, but
her DLCO was only 42% predicted, which really
started to raise my suspicion
for group one PAH in this patient and
had me thinking specifically about pursuing a right
heart catheterization.
Tom, can you tell us a little bit
more about the right heart catheterization?

(35:32):
Yeah. Absolutely.
So as we've alluded to throughout this episode,
while echocardiogram,
physical exam, history, all of these things are
really critical pieces of our workup for pulmonary
hypertension.
The gold standard is a right heart catheterization,
and we truly can't make the diagnosis of
pH

(35:52):
without that procedure.
I'm sure most of our listeners are familiar,
but a right heart catheterization
is a procedure where the catheter is placed
usually into the veins of the neck and
floated
through the chambers of the right heart,
measuring
pressures at different locations, including the right atrium,
the right ventricle,
the pulmonary

(36:13):
vasculature,
and we're getting those pressure and sac oxygen
saturation
readings at different locations.
And this is critically important because the definition
of pulmonary hypertension is based on this.
I do want to note that
as we've also been discussing,
it's important to think about your pretest probability

(36:35):
for what type of pH the patient has
because that can
inform what tests you may or may not
do during the right heart catheterization.
It I'm sure it happens, but it would
be unfortunate to have to do a right
heart catheterization
and then realize you need vasoreactivity
testing and then have to go back and
do it. Something.

(36:55):
Tom, that is a great point. Like, another
great reason sometimes to do that workup first
is that we're not just blindly throwing this
catheter in, and there are different maneuvers and
procedures we can do. So that yeah. That's
a really great point to have. Yeah. Absolutely.
So turning back to the physiology,
we've talked about how pulmonary hypertension
is defined

(37:16):
by elevated pressures that the right side of
the heart is seeing. But this could either
be due to increased resistance,
so occurring in the the pulmonary vasculature,
at the level of the lungs, at the
level of the pulmonary artery,
or it might be high pressure and volume
coming from the left side of the heart,
leading to backflow, like a system of pipes

(37:36):
backing up.
Roopali, can you tell us a little bit
about the different parameters
that we look at and how that helps
us?
Definitely, Tom. Thank you so much. And like
you mentioned, I think a lot of us
like to think about this as this plumbing
system, which will be helpful as we go
through some of the ways when we think
about the ways that we think about right
heart catheterizations. And I'm gonna go through some
of the important numbers that you should be

(37:58):
looking for in a right heart catheterization, and
I'll ask Dave to layer on some of
the important numbers as well that we should
be mindful of when we're interpreting these right
heart caths. So one thing to note is
that we have some values, as you mentioned,
Tom, in a right heart cath that we
measure directly. So those pressures that we're measuring
in the right atrium
as we go through the system or ventricle,
right, and then we wedge the catheter and

(38:20):
we get a backflow measurement, which is really
measuring the left ventricular end diastolic pressure. Right?
It's back reading that measurement. And then there's
some parameters that we actually calculate on the
right heart catheterization that are not directly measured.
So from some of these numbers that we
get and oxygen saturation numbers that we get
as we move throughout the heart, we actually
back calculate cardiac output using different metrics, other

(38:41):
stick measurement and thermal dilution measurement depending on
your institution and the NCME
report or different ones differently.
And then we use the pressures in the
cardiac output to back calculate the resistance. So
just important for us to remember what we're
actually measuring and to look at those waveforms,
and we're actually interpreting a right heart catheterization
and what we're actually deriving from those measurements.

(39:01):
So I just wanna talk about a few
key parameters that we get from a right
heart catheterization.
The first important one, because the diagnosis of
pulmonary hypertension is based on this number, is
the mean pulmonary arterial pressure or the MPAP.
So this is the average pressure in the
pulmonary arteries. And this is calculated similarly to
how we measure just normal
blood pressure based on the systolic and the

(39:23):
diastolic pressures that we measure. Remember, right, that
two third, one third? So it's the average
pressure in the pulmonary arteries. What this measurement
tells us is if the right side of
the heart is just in general seeing high
pressure for some reason. So that could be
because of high resistance in the lungs, as
you mentioned, Tom, or the most common reason
that the right heart sees high pressures because
the left heart is backing up those high

(39:45):
pressures into the right side of the heart.
So first important parameter to remember is
mean pulmonary arterial pressure. And if it's high,
it means the patient has pulmonary hypertension
because the right side of the heart is
seeing high pressures.
And the number to remember here that the
newer guidelines have supported is the number of
20. So it's greater than equal to 20,
then it's high, and that means the right

(40:06):
side of the heart is seeing high pressures.
The second number to look for on the
right heart path is the pulmonary
artery wedge pressure or the PAWP.
So what this reflects, as mentioned before, is
that left ventricle
end diastolic pressure. So this tells us again
if the right side of the heart is
seeing a high pressure, but it specifically tells

(40:26):
us is that high pressure that the right
side of the heart is seeing because there's
high pressure in the left side of the
heart that is backing up and causing the
right height side of the heart to see
that high pressure. So the number to remember
here is 15.
And then the third is the
third parameter to think about is the pulmonary
vascular resistance. That's the third number I generally
look at when I look at the right

(40:46):
heart cath. And this tells us how much
resistance the RV has to pump against in
the pulmonary circulation.
And as I mentioned, this is back calculated
with the cardiac output, some of the other
pressures that we get in this pump system,
and very important to remember the numbers and
cutoff for this as well. Dave will talk
a little bit about how we derive this.
We'll use something called Woods units, and two

(41:07):
now is the new number to remember for
this. So three parameters, very important. First, mean
pulmonary artery pressure. Second, pulmonary artery wedge pressure.
And third, the pulmonary vascular resistance. And using
those numbers, we can first say, one, does
this patient have pulmonary hypertension that's solely based
on that mean pulmonary artery pressure being greater
than or equal to 20? Two, is it

(41:28):
because do they is the right side of
the heart seeing high pressures because the left
side is backing up? And that we can
tell based on that wedge pressure. And then
three, is there high resistance intrinsically in the
pulmonary vasculature? And that we can tell based
on the pulmonary vascular resistance or PVR. And
this can be really helpful as we start
to think of those causes and groupings of
pulmonary hypertension.

(41:49):
But dates, you mentioned the guidelines have changed
a lot. The numbers are important. So walk
us a little bit through some of the
numbers and parameters and some of the more
recent changes that have come.
Yeah. Absolutely. Thanks, Rubali, for that overview. And
for anyone who is more interested in this,
doing performing right heart catheterizations,
interpreting them, what numbers you get, and certain,
some specifics, like how do you determine if

(42:10):
you're gonna use a FICC? What's the difference
between indirect and direct and thermal dilution beyond
the scope of this episode? But we have
done a prior episode on right heart catheterization.
We'll share a link in the show nights
here where we talk about those things a
little bit more specifically
of how we're
calculating the cardiac outputs, how we're using that
cardiac output to generate a pulmonary vascular resistance.
The one thing I'll mention is that of

(42:31):
the relationships you mentioned is that when you
have a mean pulmonary artery pressure
that minus your pulmonary artery occlusion pressure, your
pulmonary capillary wedge pressure is the pressure difference
in the lungs. And then that over the
cardiac output, the raw cardiac output, not the
cardiac index, however you calculated it. My preference
is for thermal dilution, but we'll, that's a
whole other episode. We'll then give you your

(42:53):
pulmonary vascular assistance in woods units. And if
you wanna
get that into dimes, you multiply by 80,
but that's how we're getting sort of these
values and those core things to remember mean
pulmonary pressure of 20, wedge of 15, and
then woods units of two.
So let's talk about the major update in
this guidelines on the definition of pulmonary hypertension
and a few things changed in this guidelines,

(43:14):
but I would say that this is a
biggest paradigm shift.
This was really in changing the woods units
classification
that we're using to identify precapillary
pulmonary hypertension.
So it's important to have a little bit
of historical perspective on this.
Previously, it used to be historically that mean
pulmonary artery pressure was defined as greater or

(43:34):
equal to 25 millimeters of mercury.
That changed with the world or the last
world pH symposium
guidelines that lowered that definition to 20
mercury.
So why did they do that? This is
all part of this effort to recognize pulmonary
hypertension
earlier and be able to bend the curve
of a patient's ongoing course.

(43:55):
Now that changed from 25 to 20 was
extremely
well evidence based I would argue. And there
are two major drivers that led to that
change.
The first is that if you look at
right heart catheterization in quote unquote normal people
or patients who do not have pulmonary hypertension,
do not have cardiopulmonary vascular disease,
19

(44:15):
millimeters from mercury is right at two standard
deviations above the mean. And so it's pretty
reasonable to say that ninety five percent of
people or the vast majority of normal people
will have the mean pulmonary artery pressure less
than 19 millimeters of mercury.
There was a big gap there between nineteen
and twenty five. And so it was reasonable
to lower the diagnosis of pulmonary hypertension to

(44:38):
20 to right above that, the upper limit
of normal.
The second is that studies of patients who
had connective tissue disease, specifically scleroderma, which are
like well known to have pulmonary hypertension and
have poor outcomes from it, showed that there
was a difference in mortality
starting at that mean pulmonary artery pressure of
20 to 25. Patients who had mean pulmonary

(44:58):
artery pressure less than 20
did better than patients that were 20 to
25, who did better than patients who were
above. So our prognostic
influence was already happening there. So they lowered
it to 20.
Now when they lowered that diagnosis to twenty
milliliters of mercury, they did not change the
pulmonary vascular resistance cutoff, which was three woods

(45:18):
units historically,
which is interesting
because those numbers are will end up being
related. Right? So pulmonary vascular resistance is calculated
for mean pulmonary artery pressure minus
pulmonary capillary wedge pressure over cardiac cardiac output.
So if you lower one of them, how
do you not lower the other one? But
it made sense in as they were recommending

(45:39):
it based on studies that we've had of
pulmonary vascular resistance. The curve is a little
bit different. And then also based on all
our trials of treatments in the past.
However, there's a new updated guidelines essentially aimed
to re inform or correct that. And so
they said, look, we're using a lower number
to diagnose pulmonary hypertension.
We should be using a lower number to

(46:00):
diagnose precapillary
disease
and recognize precapillary disease
earlier in a patient's diagnosis. So that was
the main driver for them making this change.
So I've referenced this precapillary
post capillary things a few times, and this
is what we should really take away from
our right heart catheterization
from this section is that once we have
these values and assuming the right heart catheterization

(46:22):
was well done and everything is accurate, we
can classify the patient into no pulmonary hypertension.
Pre capillary pulmonary hypertension,
isolated postcapillary pulmonary hypertension,
or mixed pre and postcapillary pulmonary hypertension. So
what are those categories?
No pulmonary hypertension. The patient's mean pulmonary artery
pressure is less than 20. Right? They do

(46:43):
not have pulmonary hypertension.
Even if the patient has a slightly elevated
pulmonary vascular resistance, they do not meet criteria
for pulmonary hypertension.
Now I, as a specialist provider, might pay
more attention to that person, but they do
not have pH.
Pulmonary mean pulmonary artery pressure above 20. They
have pulmonary hypertension.
If their pulmonary capillary wedge pressure

(47:05):
is greater than 15
and their pulmonary vascular resistance is less than
two WOODS units,
that is isolated postcapillary
pulmonary hypertension.
This is right heart overload from left heart
disease, most common
reason worldwide why you have pulmonary hypertension.
And so we do not have to think
about any of our pulmonary vasodilator

(47:25):
therapies. These patients need optimization of their left
heart function and filling pressures.
If they have,
pulmonary artery, mean pulmonary pressure above 20,
a pulmonary capillary pressure wedge pressure less than
15, and a pulmonary vascular resistance above two
woods units, they have precapillary
pulmonary hypertension.

(47:45):
They have pulmonary hypertension due to intrinsic remodeling
or process in the pulmonary vascular
vasculature.
We need to think of these patients as
having a primary pulmonary vascular disease, and that
will dictate how we monitor and end up
treating them. Now that could be seen in
patients with group one,
group three, group four, even group five disease.

(48:07):
They it doesn't tell you the mechanism
underlying of why that vascular resistance is up.
So that could be because they have hypoxemia
that's sort of just leading to hypoxia vasoconstriction
or pulmonary arterial hypertension,
but we know they have a precapillary process.
And then there are those people who have
a little bit of everything, right? So their
mean pulmonary artery pressure is greater than 20.

(48:28):
Their wedge is greater than 15, but their
pulmonary vascular resistance is also up above two.
And so these patients have combined pre and
post capillary disease, and we're gonna have to
think about optimizing multiple factors at once.
Thanks, Dave. That's extremely helpful. I was wondering
if you could just take another minute, maybe
because sometimes in clinic, we've looked at those
three parameters that we've talked about, the mean

(48:50):
pulmonary artery pressure, the wedge pressure, and then
the pulmonary vascular resistance.
But oftentimes, some patients can, especially in this
patient, my situation, say that they had developed
ILD can come in with mixed disease categories
and from group and we could have developed
group two disease as well over time. And
sometimes I ask myself in clinic, how should
I think about how much of their disease

(49:10):
is related to their group two disease or
their heart overload from the left side of
the heart versus how much is this precapular
component, so when they have mixed. But I
know there are some ways that we can
think about. Can you just touch on that
for a minute?
Yeah. This is where things get a little
bit tricky. Right? There are some metrics that
people have used. We can talk some about
the transpulmonary
gradient, right, that we this is the mean

(49:32):
pulmonary pressure over the wedge, which is above
12 would be abnormal. We could talk about
the diastolic
pulmonary gradient, which is a diastolic pulmonary pressure
minus the wedge. And seven would be the
number to remember there. Sometimes we start looking
at pulmonary artery compliance.
We're actually looking at how much stiffness is
there in the pulmonary artery by each stroke

(49:53):
volume. And these can give us some hints.
There are also other metrics in general that
we can use outside of the calf. Right?
So if we have a patient who has
group three disease specifically, like they have some
ILD, we can start looking a little bit
at the ratio of their
FVC to their DLCO. Right? So if their
FVC is only mildly reduced, but the DLCO

(50:13):
is severely reduced, Maybe a little bit less
of this is the parenchymal lung disease and
more of it is the pulmonary vascular disease.
I will say overall, none of these metrics
is perfect. It's somewhat a gestalt,
but it it's a little bit like when
you see it, you know it for part
of the times. Right? And so especially with
the pre and post combined disease, like sometimes

(50:34):
I have a patient whose pulmonary capillary wedge
is 29
and their pulmonary vascular resistance is 2.8.
And I'm like, yeah, sure. You have combined
pre and post, but this is lack heart
disease. Right? Sometimes I have a Brashear whose
wedge is 16
and their PDR is 14. And I'm like,
I don't really even care that your wedge
is elevated. This is precapular disease. Can be

(50:56):
difficult to distinguish. We can use some of
these metrics For that circumstance that you mentioned,
there's some data on trying someone on more
oxygen and seeing how much their pulmonary vascular
resistance goes down to distinguish group three versus
group one. That's a very imperfect test. So
this is where we get into some of
the art of the this practice.
Farf, that was awesome. Thanks so much for
walking us through that.

(51:17):
Once you start talking about numbers and how
to multiply and get dines,
you kinda lose me sometimes, but I love
the passion that you have for
these right heart cath numbers.
And again, in all seriousness, though, a great
job of reviewing it for us. I do
wanna go back, though, to Tom's earlier point
when he talked about potentially,

(51:37):
having a patient undergo vasoreactivity
test. Right. So now let's assume our patient's
in the cath lab,
and you have to decide whether or not
to consider vasoreactivity
testing.
I think an important point that we hope
that you get today from listening is that
this test is only indicated for patients with
idiopathic,
heritable, or drug induced pulmonary arterial hypertension, or

(51:58):
PAH.
It's performed during the right heart catheterization itself
using either inhaled nitric oxide or another short
acting vasodilator. I know that it can be
institution specific.
But what are we gonna be looking for
to see, if someone has a positive test,
and what does this actually mean if they
do?
So why we wanna do this, in in
this specific cohort of patients

(52:20):
is to see if they may benefit from
long term treatment with high dose calcium
channel blockers.
And although this is rare, this can happen,
and for these patients, it can be very
beneficial.
But a positive vasoreactivity
test is defined as a decrease in mean
pulmonary arterial pressure of greater than or equal
to 10 millimeters of mercury
to an absolute value of greater than or

(52:41):
less than 40 millimeters
of mercury
with no reduction in cardiac output.
So, again, greater than or equal to 10
through the spectrum of less than or equal
to 40 and no reduction in cardiac output.
Importantly, vasoreactivity
testing,
as I mentioned, is useful in this subset
of patients for prognostication

(53:02):
because patients tend to have a better long
term outlook and for identifying those who may
respond to calcium channel blockers, as I mentioned.
However, it's important to note that this should
not be used to predict response to other
classes of pulmonary vasodilators
despite common misconceptions.
Farf, I'm sure we can have a whole
other episode on vasoreactivity
testing, but just wanted to bring it in

(53:23):
at this point, as we're thinking about things
before we transition to other topics. Okay. Thanks
so much, Christina, for covering vasoreactivity
testing. Such an important part of thinking about
both during the diagnosis
of pulmonary hypertension and then for treatment as
well and being mindful of our treatment parameters
with those calcium channel blockers as you mentioned.
But now I'd like to shift a little

(53:44):
bit to cover screening in high risk populations,
specifically thinking about which patient population should be
screened for pulmonary hypertension.
One of these patient populations is actually the
patient population that my patient comes from, which
is the systemic fluorosis
population.
The current guidelines are coming annual screening if
the patient meets these parameters. So first, if

(54:04):
they've had disease duration greater than or equal
to three years, which my patient had,
if FVC on pulmonary function testing was greater
than or equal to forty percent, which my
patient also met, and the DLCO
was less than sixty percent as well.
So this fit my patient's profile. And so
the screening tool that the guidelines refers to
is something called the detect algorithm.

(54:26):
It's a two step process that is able
to catch
early PAH, so group one PAH in these
patients. It involves gathering some other information, including
the FEC to the LCR ratio that Dave
had previously mentioned, the NTP ProBNP that we've
talked about, and some other screening tests including
anticentromere antibodies,
looking for red axis deviation on EKG, and

(54:48):
then looking for other physical exam signs like
telangiectages.
Then once we calculate the score, if it
is high,
that's the first step of the algorithm, then
we can move to step two, which incorporates
echo findings
into this algorithm.
Specifically, we use some of those things that
we mentioned, including the TR velocity and the
right atrial size. If those are both abnormal
as well, then the recommendation is to refer

(55:11):
the patient for right heart catheterization. Because as
we mentioned, that is the definitive way to
look for pulmonary hypertension.
This two step detect algorithm has a very
high sensitivity.
So it is ideal for screening, especially before
symptoms develop. If I had been able to
follow this patient earlier before my pretest probability
was so high and she had met these

(55:31):
parameters, it would be important to think about
using this algorithm firsthand in clinic, potentially even
sending her for right car authorization
before symptoms developed in order to catch it
early.
Tom, what are some other high risk populations
we should be screening for pulmonary hypertension in?
Yep. Absolutely. As you were alluding to connective
tissue diseases, particularly

(55:52):
systemic sclerosis,
those are patients that we really need to
think about their risk of developing PAH.
But there's a lot of other conditions that
our guidelines call out that are particularly high
risk groups.
These include particularly
those with known genetic mutations
that are associated with the development of PAH.

(56:12):
The classic one that we learn about here
is BMPR two. That is probably
the most high yield one to screen patients
for. But then there's also other things that
patients will have people with cirrhosis
who develop pulmonary or I'm sorry, who develop
portal hypertension.
Those patients are at risk for developing pulmonary
hypertension.
Patients with HIV,

(56:34):
these are all pretty high risk groups.
In these high risk groups, the guidelines do
recommend annual screening.
This can occur through echocardiogram,
NT proBNP,
pulmonary function testing.
And just for a few
pearls to take away
patients with heritable PAH

(56:54):
or a known BMPR two mutation
annual echo screening is recommended. This should occur
even if patients are asymptomatic,
and this also holds true for patients with
portal hypertension.
This is particularly important if you're thinking about
someone with
portal hypertension due to their cirrhosis,
and you're gonna
think about sending them for transplant evaluation, or

(57:16):
maybe they need a tips for refractory ascites.
This often is an important part of their
evaluation process, and you should screen them, usually
with an echocardiogram.
Yeah. Great point. In the portal, pulmonary hypertension
is a super interesting topic. We've done an
episode about that, but I think maybe as
part of this series, we'll do a more
specific one because liver transplant is just such

(57:37):
a big field now. Right? And so well
tolerated.
And so they've been pushing the boundaries of
who's an acceptable candidate. And so we've been
doing more and more of these patients with
porta pulmonary hypertension
and trying to get them to goal to
get their liver transplant. Really evolving an interesting
topic. Great. Thanks so much, Verfin, Tom, for
walking us through that.
Wanna end today with a few takeaways. You've

(57:58):
had such a great discussion so far, and,
only our first
of a series in our pulmonary hypertension guidelines
that I think are gonna be really high
yield and hopefully,
very instrumental in in giving you a framework
to think about pulmonary hypertension
in your patients.
But the ESE ERS guidelines lay out a
three step diagnostic pathway for us. First, we

(58:21):
need to have suspicion of pulmonary hypertension based
on symptoms.
Second, detection with echo,
PFTs,
and labs.
And third, confirmation with a right heart cath.
I think that we demonstrated this nicely with
the case that Roopali grounded us in to
start with and that we walked through throughout,
our time together.
So thinking about pulmonary hypertension

(58:42):
early in patients with unexplained dyspnea,
especially when symptoms seem out of proportion to
PFTs or imaging.
Use the WHO classification
to guide your differential and workup.
Remember that echo helps you estimate probability, but
right heart cath is essential for our diagnosis
and classification.
And don't forget the high risk populations where
we should think about screening

(59:03):
early.
Alright. That's a wrap for today. This was
awesome. Thank you, Tom and Rapali, for guiding
us through this. I know we're just getting
started, though. In our next episode, we'll move
beyond this diagnosis, and we'll talk about risk
stratification.
We are never using just one of these
parameters. We use these combined risk scores, so
we'll cover that, talk about functional class biomarkers,
exercise testing, RV function, and hemodynamics, and go

(59:26):
through some of these common risk scores.
And then we'll start introducing our treatment categories
and go into treatment by these specific diagnoses
or groups. So really looking forward to it,
Tom Rubali, looking forward to having you guys
back very shortly. Always a pleasure, Dave. See
you guys next time. See everyone soon. Yeah.
And thank you all for listening. This episode
was written by Rupali and Tom edited by

(59:49):
myself and Christina, all recorded together. And, the
music is original music by Eric Rogers and
we'll see you next
time.