DIP Episode 353 - The Clutch Pulmonary HTN Podcast (for Step 1-3)

Okay, welcome. My name is Divine. This is episode 353 of the Divine Intervention Podcast. And in this podcast, I'm going to be talking about Poeminary Hepatension. If I'm going to call this the Clutch Poeminary Hepatension Podcast. One thing that you're going to find really useful with this podcast is I'm going to integrate so many things here. You're going to find this to be pretty useful. And again, if you're taking step 2, see case step 3 or complex level tour 3 within the next two months. In December or January, I would encourage you to sign up for the MD Me Testic and Strategy Score. So I have on the 6th of December from 2 to 4 30 pm, Mountain Standard Time. And then I have a 24-hour review course that's taking place from the 7th to the 10th of December. Again, we'll review a lot of medicine, surgery, IAAPIDS, OBGYN, psych, Neuro, Ethics, Biostatistics, Multisistemic Processes, and Disorders, Professionalism, Communication, Review all those things. So again, if you're interested, shoot me an email and I'll guide you in the right, I'll give you some more details on registration and reserving your spot. The course is going to be health through Zoom. And the review course is going to be from 10 pm to 4 pm, Mountain Standard Time on each of those days. Again, tons of people have taken these courses and they've done extremely well on their exams. I've had people have some very strong score increases as a result of the course. Okay, so let's just jump right into it.

What's pulmonary hypertension? Well, pulmonary hypertension basically is just pulmonary miniaturial pressure is over the magic number 25. That's pretty much it. And maybe the vine well, why is that a problem? Well, the reason is your right ventricle is normally a low pressure system. So if you start subjecting your right ventricle to crazy high pressures, it may not be able to handle that and over time it will ultimately fail. Now, what are some of the key areas our friends at the MB means love to test pulmonary hypertension? Well, they love to test it in terms of the causes, right? So I'm going to go through many of the causes and talk about the mechanisms behind that, right? So if they give you like a young female with pulmonary hypertension, right? I would really hope you're saying, oh, divine. You know, this person likely has pulmonary arterial hypertension from a BMPR2 mutation, right? Bon morphogenic protein receptor too, right? The BMPR2 mutation, when you have that mutation, you're going to have very strong fibrosis and viso-constriction of your pulmonary arteries. Remember, your right-itrum drains into your right ventricle and then your right ventricle drains into your pulmonary arteries. And then your pulmonary arteries drains into your pulmonary capillaries and then your pulmonary capillaries into your pulmonary veins. And the pulmonary veins into the left-itrum, right? And left ventricle and like that.

So if the pulmonary arteries are messed up, that's everything proximal to it is going to have increased pressures like the right ventricle, right? Or they can give you a question about a person that has really bad hypertension and they're an IV drug user or whatever. And you're asking, oh, what's causing this pulmonary hypertension? Well, I really hope you're saying, oh, divine, it can be methamphetamine is a very big cause, believe it or not. Especially people that use methamachronic bases can cause pulmonary hypertension. People that use cocaine on a chronic basis, it can cause pulmonary hypertension. Because again, those are very powerful visual active agents, right? Or they can give you a question about a person that is 60 years old and they've smoked two packs of cigarettes every day for 40 years. Well, those people likely have COPD. Well, if you have COPD, right? Again, you're going to be chronically hypoxic because remember, you need a surface area for oxygen to diffuse in the lungs, right? So if because of all those proteins, you've chewed up a lot of your lung pyrexamac. You're not going to have surface area for gas, oxygen diffusion, right? So you're going to be hypoxic. But when you're hypoxic, you begin to have hypoxic pulmonary visual constriction. And when you have that visual constriction, right, that's going to again constrict your pulmonary arteries. That's going to cause pulmonary hypertension, right?

Or they give you a question about a person that has like, you know, when they go out in the cold, like a female, she's actually going to be a female, she goes out in the cold, her hands turn like purple or white or whatever, right? And then they tell you that she has a hitch of dysphysia, right? Obviously, this is going to be scleroderma. It's going to be crescleroderma, right? People that have crescleroderma, they have like actual pulmonary arterial hypertension. There's nothing wrong with their lungs, but the actual pulmonary arteries are fibroast, so they get pulmonary hypertension from that. Now, contrast this with people that have like systemic sclerosis, right? Because remember, cresclerosis is the anti-central mirror. And then the anti-SEL70 antibodies, you know, for the systemic scleroderma, those people, they actually have like, interstitial lung disease, right? So the lungs are bad, unlike the cresclerosis people. They both have cresclerosis, they have interstitial lung disease itself. And in that interstitial lung disease, then causes them to have pulmonary arterial hypertension, right? It's a subtle difference, but it's very high you to know for, for your exams, right? So scleroderma can cause pulmonary arterial hypertension, right? Or they can give you a question about a person that has a thochmia, paroxysmone, an optional dyspnea, and all those things. And they ask you, why does this person have like right heart failure?

Again, it's going to be from the left heart, right? They have left heart failure that is causing right heart failure. Actually, this is very high you to know, the most common cause of right heart failure is left heart failure, okay? It's very high you. The most common cause of right heart failure is left heart failure, right? And a good way to differentiate right heart failure from left heart failure is that people that have left heart failure as the cause of the opponent hypertension, they will have a thochmia and paroxysmone, an optional dyspnea. But people that have pulmonary hypertension, not from left heart failure, will typically not have a thochmia or paroxysmone, an optional dyspnea, right? Again, it's very high you to understand those differences. Now, maybe bring in some more integrations as we go along, right? So again, if they give you a question about some guy, some old guy over the last six months to a year, you know, he's been having exercise intolerance, and then they tell you that again, you hear fine crackles when you listen to his lungs, right? He has IPF, he has a diopathetic pulmonary fibrosis. Again, that's going to cause chronic hypoxia, that's going to cause pulmonary viso constriction, you're going to fibrosis, your pulmonary arteries, you're going to get pulmonary hypertension, right?

Or he can give you a question about a person, he tell you that this person, you know, has not had very good childcare, and at birth, a whole lot of systolic murmur at the left-low external border was heard, right? And now this person has like signs of right heart failure. Again, the key thing to realize is that this person has eyes and fingers, right? Because they essentially had a VSD, blood kept flowing from left ventricle to right ventricle. But the right ventricle is not normally able to deal with those large amounts of blood. So over time, you have pulmonary arterial hypertension, and then what was previously left to right is anodic shunt, becomes a right to left cyanotic shunt, right? Because again, you've built up so much pressure in the pulmonary arteries, right? That's going to cause a reversal of flow from the right ventricle to the left ventricle, right? And obviously taking deoxygenated blood from the right ventricle to the left ventricle, right? That's going to cause the person to be hypoxic, right? Again, those people have eyes and fingers can certainly cause a pulmonary arterial hypertension, right? Or they give you a question about a person and they tell you that this person has pulmonary hypertension, and they have a history of like rheumatic fever, right? It's going to be again some kind of left heart failure that's causing the problem. In this case, mitro stenosis, right? So they have mitro stenosis.

Now mitro stenosis raised the person's left-eatural pressure, raised the person's pulmonary venous pressure, raised the person's pulmonary arterial pressure, and then they go to right heart failure, right? They got pulmonary hypertension. Now, if they give you a question about a person that is obese and snores, right? And then again, the person is having like, again, lower extremity, a dima, and all those signs of red heart failure. Then I really want you to think about OSA, right? Obstructive sleep apnea, or even obesity, hypogen, deletion syndrome. Again, these things can absolutely cause chronic hypoxia. And again, that chronic hypoxia, you remember your pulmonary vessels respond differently to hypoxia compared to the other vessels in the body. They respond with viso-constriction. When your viso-constrict, that's going to make it really hard for blood to drain from the right side of the heart. That's going to cause right heart failure, right? Again, that's going to cause pulmonary hypertension. Or if you even have chronic P Es, right? You see people with fat P Es, and they just seem to have never gotten better from that PE, right? You want to think about, in fact, this is something they call CTEPH, right? Chronic thrombone, volic pulmonary hypertension, right? Where they've had like P Es that the body just never really takes care of, right? So those chronic obstructions, right, again, cause pulmonary hypertension and the right heart failure, right?

So again, you know, I kind of made this big deal about orthopnea and paroxysmonectional dyspnea, telling you that, oh, you have right heart failure because of a left heart problem. Let me tell you this. You can get pulmonary hypertension from problems just with your pulmonary arteries. That's it. In that case, you will not have orthopnea or paroxysmonectional dyspnea. But if you go more distal in that pathway, you can have pulmonary hypertension from a pulmonary venous problem, pulmonary venous hypertension, right? Venous hypertension. Because if you think about it, right, right, right, atrium to right ventricle, right ventricle to pulmonary artery, pulmonary artery to pulmonary capillary, pulmonary capillary to pulmonary vein, pulmonary vein to left atrium, left atrium to left ventricle, right? So the thing is whenever you have a problem before the capillaries, before the pulmonary capillaries, right, like a problem in the pulmonary arteries, for example, then you're not going to have orthopnea or paroxysmonectional dyspnea because those are usually problems you have when your lungs are wet. People that have pulmonary arterial hypertension, the problem is prior to the pulmonary capillaries. So they are lungs because remember, capillaries tend to be more permeable, right, because they have simple, simple epithelium, right? So the thing is when people have a pulmonary arterial problem, blood is not really getting to the pulmonary capillaries that much, right?

So the hydrostatic pressures in the pulmonary capillaries are low. So they're not having a lot of fluid extraversation from the pulmonary capillaries. So they don't have orthopnea or paroxysmonectional dyspnea. However, if a person has a problem with a pulmonary vein, right, if the pulmonary hypertension is caused by pulmonary venous hypertension, right? Say for example, from a problem with the left e-trium or microstenosis or whatever, then the pulmonary vein is going to have increased pressures. And remember, your pulmonary vein is distal to your pulmonary capillaries, right? So because your pulmonary vein has increased pressures, then there's going to be a backup of fluid in the pulmonary capillaries. That's going to raise the hydrostatic pressures of those pulmonary capillaries. You're going to have fluid extraversation and you're going to get problems, right? You're going to get a thopnea and paroxysmonell paroxysmonell, nocturnal dyspnea. Again, so it's very important. Pulmonary arterial hypertension is a problem proximal to the pulmonary capillaries. So you're not going to have a thopnea or paroxysmonell nocturnal dyspnea. Now pulmonary venous hypertension is a problem that is distal to the pulmonary capillaries. So you're going to have increased hydrostatic pressures and the pulmonary capillaries, you're going to have fluid extraversation into the pulmonary pyroenchema. You're going to get a thopnea and paroxysmonell nocturnal dyspnea.

Then some other thing I guess I would mention here, whenever a person has pulmonary hyper-right heart failure because of something that's in their lungs, because of a pulmonary problem like COPD or whatever, we call it corpomunali, right? Corpomunali. But if you have right heart failure from a left heart problem, we do not call it corpomunali because the problem is from the left heart, not from the lungs. And don't forget cystic fibrosis, right? It can also be one of those things that causes pulmonary hypertension, right? Because again, those people are chronically hypoxic, they have chronic lung disease. That's going to cause hypoxic visual constriction. That's going to cause right heart failure, right? That's why cystic fibrosis again, you know, can cause just many problems along term, right? And then usually if you're listening to a person's heart that has pulmonary hypertension, you'll tell you that they have like a loud S2-heart sound, right? A loud pulmonica heart sound, right? And again, if you have pulmonary arterial hypertension many times, because your right ventricle is having to generate so much force to force blood through the pulmonary artery, you're going to get a concentric hypertrophy of the right ventricle. That's very high you to know. You're going to get a concentric hypertrophy of the right ventricle, concentric hypertrophy of the right ventricle, right? So essentially what's happening there is you're stacking your sacramirs in parallel. Right?

You're stacking your sacramirs in parallel. Right? Again, one other thing I think that may be helpful here. Again, I'm telling you the reason I'm making this podcast. Once someone requested it and two I was like, ah, there's some really high-year things that the immune system could test here. They could actually try to see if you can, if you have an understanding of the physiology in differentiating pulmonary hypertension, like pulmonary hypertension, secondary to like pulmonary arterial hypertension, versus pulmonary hypertension secondary to left heart failure. So think about it. If you have pulmonary arterial hypertension that is causing, ah, right heart failure, then your right heart pressures are going to be increased, like your CVP, your central venous pressure is going to be really, really high. But since you have pulmonary arterial hypertension, not even sending blood to the left side of the heart. So your left side heart pressures will be normal or decreased, right? So in people that have pulmonary arterial hypertension as their cause of right heart failure, their CVP is going to be up, but their PCWP, which is a surrogate for left-itre pressure will be normal or decreased because blood is literally not getting to the left side of the heart.

But if a person has left heart failure as the cause of their pulmonary hypertension, which is leading to right heart failure, since the left heart is messed up, then the left-itre pressures are going to be up, and the right-itre pressures are going to be up as well. So these people's PCWP, the pulmonary capillary wedge pressure, which is a surrogate for left-itre pressure, and the CVP, which is central venous pressure, which is a surrogate for right-itre pressure will both be increased, right? Another way they can even test pulmonary hypertension is they can give you a question about a newborn that has completely, you know, that is hypoxic, right? And you notice that, huh, this newborn is totally fine. Like you get an echocardiogram, you notice that there's nothing wrong, like the cardiachanadomy is completely normal. But you just notice that blood is still flowing from the right-itreum to the left-itre, right? Like the person seems to have like that fetal circulation that is just remaining persistent. Well, that is something that's called persistent pulmonary hypertension of the newborn, right? Persistent pulmonary hypertension of the newborn. Sometimes they call this persistent fetal circulation on MDME exams. Basically, you just notice that one. This newborn is hypoxic. So you're like, huh, is it that this newborn has like some cyanotic, congenital heart defect, like, you know, tetralogy of flow or transposition of the great vessels.

But they will tell you in the queue, that echocardiography shows normal cardiachanadomy with a persistent right to left shot. Whenever you see stuff like this, I want you to think about persistent pulmonary hypertension in the newborn. Sometimes they call this again persistent fetal circulation, right? Now, what are the key chemical agents that can appear rolling in pulmonary hypertension? Well, actually, you know, it's kind of fascinating in a science. But if you really think, if you understand this, it will make the treatments make a ton of sense to you, right? So the pathophase, right, in general, people with a half pulmonary hypertension usually have like decreased production of vasodiliders, right? Things that dilute the pulmonary arteries, right? So things like prostaglandins or nitric oxide, right? So you may say, oh, why does how does nitric oxide help with this vasodilation? Well, if you think about it, remember, nitric oxide is made many times in endothelial cells. And many times is made from the amino acid arginine, right? So arginine, right? Nitric oxide synthase will convert it to nitric oxide. And then that nitric oxide is a very powerful activator of guanilit cyclase, right? You activate guanilit cyclase, that will convert GTP, so guanosine triphosphate to cyclic GMP, right? And then that cyclic GMP activates protein kinase G, which then causes you to have smooth muscle relaxation and that will cause viso dilation.

And the thing is that cyclic GMP is actually broken down by an enzyme in the lungs known as phosphodistory is 5. PDE5 breaks down cyclic GMP and you also find PDE5 in many other tissues of the body, right? But PDE5 breaks down cyclic GMP. So, but we know that, oh, if cyclic GMP is around, you'll activate protein kinase G more, you get viso dilation. So, in general, right, phosphodistory is 5 activity. If it's working really well, it's reducing your amount of cyclic GMP and that's ultimately causing a viso constriction, right? If you understand all these things, then you'll understand how the how pulmonary hypertension is treated. And I guess another thing I should also mention is endothelene is an agent that is, I mean, look at the name endothelene. So, that means he's meeting endothelial cells, right? It's meeting endothelial cells, right? It's a very powerful viso constrictor, right? It's a very powerful viso constrictor. So, how do we treat pulmonary hypertension on NBM Es? Well, you can give a phosphodistory is 5 inhibitor, right? So, if you inhibit phosphodistory is 5, your cyclic GMP is going to build up and that's going to help, right? That because you're going to have more viso dilation, right? So, these are going to be drugs like Vardena-Fel or Seldena-Fel, right? Or you can even give something that blocks these endothelian receptors, right? So, it's going to be something like Ambricentan or Bocentan, right?

You block those endothelian receptors, you get a net viso dilation, right? And again, remember I said that decreased synthesis of things like prostaglandins and nitric oxide is what causes a person to have this net viso constriction that causes pulmonary hypertension. So, if you give a prostaglandin analog, right? So, something like ILO-prost, so that's spelled ILOPROST, right? Or Ipo-prostinol, right? Ipo-prostinol, like Ipo-PRO-ST-ENOL, right? Ipo-prostinol, that's a PGI2 analog. Do you remember PGI2? It's a Plytlet-Gatherin inhibitor, right? If something's inhibiting Plytlet-Gatherin, it'll make sense that it's also a very good viso dilator, right? So, ILO-prost, Ipo-prostinol, you can even see TREPR-ST-ENIL on your exam, T-R-E-P-R-O-F-T-I-N-I-L, TREPR-ST-ENIL, right? TREPR-ST-ENIL, TREPR-ST-ENIL, right? So, those are always your TREPR-POMENERI hypertension. If you don't see any of these drugs for some reason, you can actually give a calcium channel blocker, right? High doses of a calcium channel blocker, although it works in only about 5 or so percent of people that have pulmonary hypertension, it's like, there's this kind of pulmonary hypertension called visor reactive pulmonary hypertension. Again, there's some challenge testing you do for that, but that is well beyond the scope of our discussion right now. It's kind of the kind of thing you talk about like, I am a resident or pulmonary fellow, so we're gonna skip that for now, right?

So, I guess to wrap up today, how do we diagnose pulmonary hypertension? Well, this is easy. All you need to do is first, get an echocardiogram, right? Get an echocardiogram, right? Because the echocardiogram is sure you, if the person has like right ventricular problems or right ventricular wall thickness or things like that. But to confirm the diagnosis, right? So, the echocardiogram is like the screening test. The diagnostic test is actually a right-hot cuff, right? So, right heart catheterization, right? Basically, you pass a swan-gans catheter that will give you like very good accurate measurements of your pulmonary pressures and your PCWP and all those things, right? So, that's how you diagnose pulmonary hypertension. So, I think I'm gonna go ahead and stop here. Again, as I do at the end of every podcast, I do offer one or one tutor for all the USMEL exams. Step one, step 2 CK, step three, complex level one, two, and three, except OMM, pre-clean, comets, school exams, 30-ish-off exams. I offer again review courses for the USMEL exams, especially step 2 CK and step three and complex level two and three. Again, I have one coming up between the 6th and 10th of December. That's the one you want to attend if you're taking your test in December or January. I'm almost certain I'm not gonna be hooting a course in January. And then, I have these podcasts on Apple Podcasts, Google Podcasts, and Spotify, at least the most recent 150.

If you want everything from episode one, all the way to 353, then you need to go on the website, and then I have a You Tube channel, right? Divine Intervention, USMEL podcasts and videos. That's where I post the videos that I make. Please subscribe, again, any little bit of support certainly helps. And then, I have a new website called Divine Intervention, Life Lessons.com. So, I make podcasts like Life, podcasts that just deal with life lessons. Again, many people have found this, we really hope for. I won't have the podcast on Apple Podcasts. It's called the Divine Intervention, which is a very good idea. On Apple Podcasts, it's called the Divine Intervention, Life Lessons. So, again, if you're interested, feel free to subscribe to that. And then, I help with ERA's applications with, you know, like mock interviews, personal statements, and all those things. I do a lot of application consulting, again, I've been on an admissions committee, and I've worked with tons and tons and tons of people that are residents all over the country. In fact, some of the people I've worked with are gonna be graduating, I think, next year or something like that. Or, if even we'd be graduating this year, anyway, right? So, if you're interested in any of those things, just shoot me an email through the website. Or you can send me an email at Divine Intervention Podcasts with an SAD end at gmail.com. So, thank you for listening to me. Have a wonderful rest of your day. God bless you. Thank you.

Pulmonary arterial pressure exceeding 25 mm Hg.

Left heart failure (e.g., due to mitral stenosis or cardiomyopathy).

Orthopnea and paroxysmal nocturnal dyspnea (PND), because the problem is distal to the capillaries (pulmonary venous hypertension).

In isolated PAH, PCWP (surrogate for left atrial pressure) will be normal or decreased, while CVP (right atrial pressure) will be high.

PDE5 inhibitors (e.g., Sildenafil/Vardenafil).

CREST involves primary PAH due to vascular fibrosis; Systemic Sclerosis often causes PH secondary to Interstitial Lung Disease (ILD).

BMPR2 mutation.

Vasodilators; Iloprost ($\text{PGI}_2$ analog).

Initially Left-to-Right (L $\rightarrow$ R); high PA pressure causes reversal to Right-to-Left (R $\rightarrow$ L) cyanotic shunt.

Hypoxia triggers hypoxic pulmonary vasoconstriction, constricting the pulmonary arteries and raising resistance.

No, because the problem is proximal to the pulmonary capillaries, meaning hydrostatic pressures in the capillaries are low.

Chronic Thromboembolic Pulmonary Hypertension; caused by chronic thromboembolism (P Es that the body fails to clear).

BMPR2 mutation.

Vasodilators; Iloprost ($\text{PGI}_2$ analog).

Initially Left-to-Right (L $\rightarrow$ R); high PA pressure causes reversal to Right-to-Left (R $\rightarrow$ L) cyanotic shunt.

Hypoxia triggers hypoxic pulmonary vasoconstriction, constricting the pulmonary arteries and raising resistance.

No, because the problem is proximal to the pulmonary capillaries, meaning hydrostatic pressures in the capillaries are low.

Chronic Thromboembolic Pulmonary Hypertension; caused by chronic thromboembolism (P Es that the body fails to clear).