Transcript
Speaker: Welcome to Critical Matters, a sound podcast covering a broad range of topics related to the practice of intensive care medicine.
Speaker: Sound provides comprehensive critical care programs to hospitals across the country.
Speaker: To learn more about our programs and career opportunities, visit www.soundphysicians.com.
Speaker: And now your host, Dr. Sergio Zanotti.
Speaker: In today's podcast episode, we will discuss the management of acute type B aortic dissection.
Speaker: Our guest is Dr. Firas Musa, a vascular surgeon and professor of vascular surgery at McGovern Medical School at UT Health Houston.
Speaker: Dr. Musa also holds a joint appointment with Imperial College in London.
Speaker: A renowned surgeon, investigator, and educator, his clinical interests include open and complex endovascular repair of thoracic and abdominal aortic aneurysms, type B aortic dissections,
Speaker: carotid stenosis, lower extremity, and mesenteric ischemia, among others.
Speaker: It is a great honor and a privilege to have him as our guest today.
Speaker: Firas, welcome to Critical Matters.
Speaker: Thank you so much, Sergio.
Speaker: It's a great honor to be with you today.
Speaker: I'd like to start with a question of perspective.
Speaker: Why should intensivists care about type B dissections?
Speaker: Yeah, I think if you asked me five years ago, I would have to scratch my head a little bit more.
Speaker: But now I'm more and more convinced that aortic dissection or aortic disease in general is a multidisciplinary team approach.
Speaker: And for aortic dissection in particular or any acute aortic event,
Speaker: intensivist is almost as important as a surgeon.
Speaker: In aortic dissection in particular, half the people are treated medically and this medical treatment is done in the ICU under the supervision and auspices of a team of an intensivist with his or her team.
Speaker: And that is really being aware of what the medications are
Speaker: But the goals of blood pressure and heart rate and how to adjust that and be up to date on what are the best agents to use.
Speaker: It's really within the realm of both surgeons and intensivists.
Speaker: And I would argue intensivists play a big role in making sure the patient do well.
Speaker: Perfect.
Speaker: And you talked about acute aortic disease.
Speaker: So a good follow-up would be maybe defining some of these acute events.
Speaker: Acute aortic dissection, intramural hematoma, penetrating aortic also seem to be all bundled in a cluster that we have to differentiate.
Speaker: Could you tell us a little bit more about that?
Speaker: Yeah, sure.
Speaker: So these are what you call what you just listed are what's called acute aortic syndromes.
Speaker: So the section intramural hematoma and penetrating aortic ulcer lumped up, summed up in one.
Speaker: However, they're distinctly different pathologically and even their risk factors, honestly.
Speaker: But
Speaker: For acute aortic section, it's commonly known, it's a tear in the innermost layer of the aorta, which is the intima, and then the blood goes into and separate between the intima and the media, and you have what's called a true and false lumen.
Speaker: That is the classic description and the most common of the three.
Speaker: Less common, equally important, and could be argued as a
Speaker: as a pre-pathology to dissection is intramural hematoma.
Speaker: And that usually gives me a pause because pathologically, it's a bleeding in the vasovasorum of the media.
Speaker: And that leads to a plot.
Speaker: It's like, you know, ecchymosis, if you will.
Speaker: If when you hit your skin, if you hit your head,
Speaker: or armed, let's say, against a pole or something or get hit or
Speaker: you end up with a bruise and ecchymosis, and that blood is in the subcutaneous tissue, and you can see it on the skin.
Speaker: Similarly here, intramural hematoma, blood is in the media and then spreads throughout the aorta and form an intramural hematoma.
Speaker: However, there is no distinct tear that you can see then flow into
Speaker: two lumens, so then they're distinctly different, and many of them disappear or go away or heal
Speaker: over time, just like an ecchymosis heal over time, and that time is variable.
Speaker: And some of them do convert to a frank aortic dissection and get treated just like an aortic dissection.
Speaker: So thankfully, it's less common, less headache to deal with.
Speaker: Same treatment strategy as aortic dissection.
Speaker: Distinctly different is penetrating aortic ulcer, which is atherosclerotic in nature.
Speaker: Most of the time, patients who have
Speaker: who has smoked all their life and so on.
Speaker: It looks like a peptic ulcer, if you will, but it's an atherosclerotic.
Speaker: It's an outpouching.
Speaker: It could be also described at some point as a secular aneurysm.
Speaker: The pathology is atherosclerosis, and then the treatment would be variable,
Speaker: depending on size, symptoms, presence of symptoms, and definitely size and depth, how far into the, how big into outside the lumen of the aorta, and how wide is the mouth, if you will, of that penetrating aortic ulcer.
Speaker: So these are three different symptoms.
Speaker: and presentation of an acute aortic syndrome.
Speaker: By far, the most common and most studied is acute aortic section.
Speaker: In terms of the epidemiology of acute auric dissection, could you comment on the incidence and main risk factors?
Speaker: Right.
Speaker: So, incidence classically described as anywhere from 2 to 6.
Speaker: And as I'm finding out more and more in the trial, to be honest, it's more around 2 to 3 per 100,000 patients.
Speaker: Or, you know, you can argue three to four depend on the season per 100,000.
Speaker: So in a country like the United States would be with, let's say, 300 million, you'll find like three to 4,000 cases per year of acute aortic dissection.
Speaker: And that includes both type A and B. Slightly more A, probably, if you...
Speaker: count, if you try to be slightly generous, we'll end up around that number to 5,000 new cases per year for a country like the United States.
Speaker: That's in terms of men and women tend to be
Speaker: This tend to be, like most aortic diseases, underdiagnosed in women, but the incidents tend to be similar, slight predominance in men.
Speaker: But as they age, probably they're both similar incidents in men and women.
Speaker: Less known in other minorities, like African Americans and Asians, it's definitely, it's a,
Speaker: well-known described entity in Japan and China and Korea and treated the aorta dissected at different diameters.
Speaker: Now, risk factors are universal around the world.
Speaker: I like to tell patients and tell even providers that it's
Speaker: Aortic dissection is not a disease of technology or, you know, which devices and whatnot.
Speaker: It's primarily a disease related to hypertension in 9 out of 10 cases.
Speaker: It is uncontrolled hypertension is the number one cause or risk factor.
Speaker: The one that's less common but also important is connective tissue disorders like Marf and Louise Dietz, Vazcarina Helios-Enlows, that is, and many other genetic aortic erotopathy.
Speaker: And then important, and there are pockets in the country that,
Speaker: That's more than others, but it's everywhere, prevalent everywhere, is the use of illicit drugs, most importantly, cocaine and meth.
Speaker: Wherever you see cocaine and meth use, especially in younger folks, this spikes blood pressure at a very high level, and this spikes lead to an aortic section.
Speaker: We've seen that.
Speaker: throughout the country.
Speaker: And these are the three most common risk factors, but by far it is hypertension, just like smoking and peripheral disease.
Speaker: Classification of aortic dissections has important implications for therapy and understanding the disease and making sense of the anatomy.
Speaker: Could you tell us what are the current systems that are relevant and how they should be viewed by non-surgeons?
Speaker: Right.
Speaker: So that's, I agree.
Speaker: It's an important topic.
Speaker: So just to give you a little bit of a historic background, King George II died in 1760 of presumed type A aortic dissection.
Speaker: Okay.
Speaker: So that's 1760.
Speaker: Nothing happened till 1760.
Speaker: till the year of 1954 when DeBakey and the Dream Team here in Houston actually described the disease as type 1 and 2 and 3 and 3 was divided in 3A and 3B according to DeBakey classification.
Speaker: And then 20 years later, in 1970, Shumway and Daly came up with the Stanford classification.
Speaker: So today,
Speaker: DeBakey and more commonly Stanford classification is probably still the most commonly used is Stanford.
Speaker: You hear people talking about Stanford A and B. And that's really refers to Stanford A, refers to a dissection or a tear that involves the ascending aorta.
Speaker: And the ascending aorta definition, if you read it in the
Speaker: in our paper in the New England Journal, it is really delineated by the medial border or around the medial border of the innominate artery.
Speaker: So anything below that between the valve and the innominate artery is considered type A.
Speaker: Anything between the middle or kind of the lateral border of the nominate or is considered after that to be type B aortic section.
Speaker: And that's, I think, is slowly giving way to the newer classification that came up by the site of astral surgery, site of thoracic surgery, which is so the SVS STS zone one to 12, which I think,
Speaker: To their credit, I think it's more descriptive because if you're on the other end, like you're the intensivist, you're on the phone, and you're talking to the surgeon on the other end, if I tell you there's a type B, this could be anywhere.
Speaker: It doesn't tell you the, maybe tells you where the tear is, but doesn't tell you the extent.
Speaker: Here it tells you the tear and the extent goes from zone one to zone six or zone five or six or eight or nine.
Speaker: So if you have the table in front of you, it makes it easier for the person on the receiving end.
Speaker: Imagine it's two in the morning and I'm describing this to you.
Speaker: It wouldn't make sense unless you have really a visual.
Speaker: but zone 1 to 6.
Speaker: Now, this, in terms of making communication easier, and also has implications on therapy because, obviously, type A is treated differently than type B. And if you have a zone 1 or zone 2, zone 0, 1, 2, the treatment is different than what it is in zone 3, 4, and 5, and 6, 7 would involve 5, 6, and 7 would involve the viscera.
Speaker: So you're kind of...
Speaker: thought process would differ in terms of what you need in terms of stingraft or hybrid repair and so on.
Speaker: So these are the implications on
Speaker: There are new classifications that is less commonly used, especially in this country, but most parts, Stanford and the new SVS-SCS probably are more commonly used these days.
Speaker: Don't say that to the group at the Baytee Heart Center.
Speaker: For sure.
Speaker: But like you mentioned, we're both in Houston, so the historical context is always very important, right?
Speaker: Of course.
Speaker: We're pioneers in understanding history.
Speaker: and creating interventions for acute aortic disease.
Speaker: So Stanford, like you mentioned, is also what I believe most intensivists are familiar with.
Speaker: And from a very simplistic perspective, type A, you think, okay, we need surgery immediately.
Speaker: Type B, I need to talk with surgery, but we have a time to figure out what to do.
Speaker: Now, the SVS, STS that you mentioned in your wonderful review paper recently published in the journal that we will link in the show notes is probably something we should be aware of in terms of providing more precision in our communication.
Speaker: Right.
Speaker: Right.
Speaker: So like you mentioned, if I call you with a consult in the middle of the night or whatever, and I can tell you what SVS, STS zone model is affected, it gives you a much better perspective of what's going on and what are probably the next steps to take.
Speaker: So I would equate it for our intensivist listeners to talking with a neurointerventional person and giving them an NIH stroke scale.
Speaker: Yeah.
Speaker: It adds precision.
Speaker: And we can all speak the same language of what's really, really happening.
Speaker: Now, that would be amazing.
Speaker: Yeah, correct.
Speaker: So that would be phenomenal.
Speaker: We will work on that.
Speaker: I'm sure that it's still not the common pattern.
Speaker: But have you experienced a pickup in radiologist reporting SVS, STS, or they don't really go into that?
Speaker: No, not really.
Speaker: I mean, and it does pick up among trainees in surgery.
Speaker: So now is a resident calling me and telling me this is on one to five or something like that, which is,
Speaker: Which is helpful.
Speaker: But as you said, I think it's exactly like the NIH score.
Speaker: If you could, it would be incredible.
Speaker: As I said, I think the intensivists play a key role in understanding the anatomy for the intensivists, which I think their role is just as important as the surgeon.
Speaker: in a multidisciplinary team, we all should be speaking the same language and be on the same page.
Speaker: That would be ideal.
Speaker: Yeah, I agree.
Speaker: And the last classification, which I want you to comment on briefly, we're going to dive in in more detail to talk about management.
Speaker: But I also believe extremely important for type B, specifically dissection, is complicated versus uncomplicated.
Speaker: Right.
Speaker: So, um, the, the, um, in specific in type B, um, so type actually before the type A would be, would be the most of the time it's a fatal disease or, or, you know, it needs this urgent therapy because of either severe AI or a cardiology of fusion or secondary rupture or, um, you know, or malperfusion.
Speaker: Most of the time it's associated with type A or a coronary event, which is a malperfusion.
Speaker: In type B, luckily most of the time it is, there is none of that.
Speaker: There is no rupture and there is no malperfusion and that is called uncomplicated.
Speaker: So,
Speaker: In other words, uncomplicated type B aortic section is any dissection without evidence of rupture or malperfusion.
Speaker: And malperfusion can happen to the cerebral, but more commonly into the mesenteric, so SMA, celiac, or the renal, or the leg.
Speaker: Okay, so the iliac goes out, one of the kidney arteries go out, or both.
Speaker: Celiac or the SMA, most importantly, will go out.
Speaker: These, in the absence of rupture or malperfusion, this would be considered uncomplicated.
Speaker: If they present with any of those signs of malperfusion,
Speaker: then it is complicated type B dissection.
Speaker: And this is really what the FDA defines, complicated aortic dissection.
Speaker: This was what led to the approval of Stengraft.
Speaker: It is that showed that Stengraft work, and we'll touch base on that.
Speaker: Maybe what showed that Stengraft work is because in the incidence of, or in the presence of rupture and malperfusion, Stengraft will probably be life-saving.
Speaker: So because it will redirect flow or patch, patch a rupture or redirect flow and resolve malperfusion.
Speaker: And again, we're emphasizing the classification and the vocabulary so that communication can be efficient and effective.
Speaker: Right.
Speaker: I always tell people when you call a colleague from another specialty, if you know the right words to use, you will always get their attention.
Speaker: Right.
Speaker: Right.
Speaker: Yeah, so I mean, if you call me for an aortic section and say, hey, Moosa, this is a type B aortic section zone 1 to 5 or type B aortic section with evidence the guy is hypotensive and blood pressure is 80 over 60, which is obviously in type A, B aortic section, the cause of their blood.
Speaker: of their dissection is usually hypertension.
Speaker: So if they are hypotensive, that means they are in a shock, and that is really what would be a complicated type B. Similarly, hey, Musa, this is a type B aortic section came in just now, and his leg is cold, and it cannot move it, and has no pulse in it.
Speaker: So that is malperfusion.
Speaker: And that is really get me out of bed right away and start driving towards you.
Speaker: Excellent.
Speaker: I actually, when you mentioned that second case, I recall a case that came through the ED with a cold leg after taking cocaine and everybody was focused on the cold leg and it was a type B dissection.
Speaker: Once you do the proper workup, it's much more extensive.
Speaker: Yeah.
Speaker: Yeah.
Speaker: It could be missed anywhere in the world, to be honest.
Speaker: It's crazy.
Speaker: So in terms of initial clinical management of acute type B dissection, could we start with diagnosis, clinical presentation, and from your perspective, what's the gold standard for imaging?
Speaker: And are there any other tests that we should be considering initially?
Speaker: Right.
Speaker: I think this is a very important topic because, as we mentioned in the paper, it gets missed many times, and that led to a huge worldwide Think Aorta campaign in this country and Europe and everywhere.
Speaker: that you think of aortic section or an aortic event, acute aortic syndrome, when patient presents.
Speaker: So initially, the classic presentation of a tearing chest pain, it is real.
Speaker: It does happen.
Speaker: Especially, you know, it happens suddenly.
Speaker: It's not like it's been going on.
Speaker: So a patient comes in with really a few hours, not a few days history of severe
Speaker: chest pain.
Speaker: This pain will bring you in that same day, okay?
Speaker: That's first hint.
Speaker: And the second hint, so mostly is the pain, you know, and then the second thing or the sign is the hypertension.
Speaker: So pain and severe hypertension, we're talking anywhere from 160 to 180, 200 diastolic over
Speaker: So, you know, 110 diastolic in a person may or may not be taking their blood pressure pills or not known to be hypertensive.
Speaker: This should alert you to an aortic dissection.
Speaker: So pain and hypertension should equal.
Speaker: section to the top of the differential in anyone's mind, in the ED, in the ICU, and so on.
Speaker: So the gold standard nowadays in 2025 is CTA of the chest, abdomen, and pelvis.
Speaker: Chest, abdomen, pelvis, not enough.
Speaker: Even if the patient has renal insufficiency and so on, CT scan without contrast is useless for this diagnosis.
Speaker: Cannot tell me anything, as you can imagine.
Speaker: It can't tell if there's malperfusion, if there's a rupture.
Speaker: So it becomes, I would be...
Speaker: I can't remember how many times I've told this to the intensivist or the, actually, it's usually the ED when it's like, you can't tell me it's patient has an aortic section on a non-con CT scan.
Speaker: So CTA, chest, abdomen, pelvis, should be the first immediate procedure.
Speaker: test for, obviously, at the same time, you would have done cardiac enzymes and EKG by the time they come and get the patient to do the CTA.
Speaker: It's 10
Speaker: Usually if it's positive, just like PE, it is more indicative of an acute aortic event.
Speaker: If it's negative, it does not rule it out.
Speaker: But definitely, this is a presentation and CTA from the initial presentation.
Speaker: Is there a role for echocardiography emergently or that's more for… Right.
Speaker: So, ECHO used to be, when I was growing up, ECHO used to be the gold standard, if you will, before the 64 slice, and it tells you how old I am, before the 64 slice and now 128 and God knows 230, or the presence of CT scan in the emergency department, ECHO.
Speaker: Now, ECHO could miss some areas in the heart.
Speaker: ECHO's still key in type A more than type B.
Speaker: aortic section.
Speaker: But I think for the general immediate diagnosis, it is kind of taking a back seat.
Speaker: I think it's important in the operating room to have an echo for many reasons for diagnosis and also to treat to guide therapy as well, just like an intravascular ultrasound.
Speaker: But definitely taking a back seat to CTA.
Speaker: Any other tests that you would recommend?
Speaker: I guess these days we get a bunch of tests in the ED anyways, but obviously creatinine would be helpful as a potential sign of hyperperfusion.
Speaker: Anything else?
Speaker: No, I think you hit it right.
Speaker: I mean, I think kidney function and full cell labs, I mean, the usual tests that come in, it depends on the scenario of patients hypotensive and anemic.
Speaker: And you have, that will explain the CT scan with a bloody pleural fusion, if you will.
Speaker: So there is nothing particular if you're asking.
Speaker: There is nothing except that, as I said, the markers of D-dimer.
Speaker: There are a bunch of other tests, other markers have been tested, but it's really hasn't been that widely used.
Speaker: But only probably D-dimer has been circulated as potentially, you know.
Speaker: But as I said, if it's negative, that does not rule it out.
Speaker: That's it.
Speaker: Just full set of CBC and chemistry should be helpful to guide therapy and also guide diagnosis and therapy.
Speaker: In terms of, and usually these patients, it comes through the ED, they're diagnosed in the ED, and immediately, obviously, vascular surgery and CT surgery, depending on the type of dissection, will be alerted.
Speaker: They usually are, I mean, they should be admitted to the ICU, as we mentioned earlier.
Speaker: What are the initial considerations for medical management of a type B aortic dissection?
Speaker: So I think this is the initial management is so important for type B. And that is where I think intensivist, I mean, you could, you can slice, it's like vascular surgeons.
Speaker: There are general vascular surgeons, there are aortic vascular surgeons, and there are carotid vascular surgeons and so on.
Speaker: There's dialysis and peripheral vascular disease.
Speaker: Here you could, same thing with it.
Speaker: There's
Speaker: CV anesthesia and so on.
Speaker: Here you can have a similarly dedicated ICU team led by an intensivist who is well-versed in aortic disease.
Speaker: So let's, let's, I'm going to spend a minute here on ICU management because I think
Speaker: if I learned anything so far from the trial that currently I'm running, is the ICU management could definitely change the course of the patient in the hospital and therefore even post-discharge.
Speaker: And here's how.
Speaker: We usually treat those patients with, still is, we still do, with a drip of what's called anti-impulse.
Speaker: meaning you treat the blood pressure to guideline therapy, blood pressure of a game of aim of a systolic of 120 and a heart rate below 120 and below and a heart rate below 80.
Speaker: And the same time, strict eyes and nose, make sure they're not really over hydrated, concentrate drips, make sure their urine output is monitored.
Speaker: You put a
Speaker: A-line and a Foley and, you know, make sure they use their incentives parameter and so on.
Speaker: And however, the drips, we used to use Esmolol, which is still in most, even in probably in our place, we use Esmolol.
Speaker: And I'm finding more and more that probably non-selective blockers like Levitolol,
Speaker: and we're investigating labetalol instead of esmolol, for instance, as an initial therapy, and also add oral medication at the time of presentation, would probably be worth switching to, if you will.
Speaker: Now, this is not a recommendation for everyone to adopt everywhere and start to boost aceto.
Speaker: It is an important...
Speaker: topic to evaluate per ICU.
Speaker: And I've seen it's now published in, I think the group in Wisconsin have published a good paper on their medical management of type B aortic section.
Speaker: So esmolol instead of, labirinol instead of esmolol has been linked to shorter ICU stay, shorter hospital stay,
Speaker: and better blood pressure control when they go home.
Speaker: There's a whole protocol for that.
Speaker: So as blood vitilose is first line IV therapy,
Speaker: plus amlodipine PO, then you switch to teltiazem, then, excuse me, you switch to cardine drip, then another calcium channel blocker, and then you add on oral and IV if you need a second line.
Speaker: Second line oral would be Losartan, for instance.
Speaker: So my point is, there is evolving
Speaker: change or evolving medical therapy in the ICU.
Speaker: And this medical therapy in the ICU will dictate the course in the hospital.
Speaker: And if they did not have a complication in the hospital, they're not likely to have a complication when they go home.
Speaker: And that is really important.
Speaker: And, you know, and that starts in the ICU initial management, if you will.
Speaker: And that is what I wanted to get people to know and understand that ICU team, like next time you see an aortic dissection, you're not going to just wait for your vascular surgeon to tell you.
Speaker: You're going to have a discussion with the vascular surgeon about the evolving therapy and how you can actually improve the outcome all around.
Speaker: And you mentioned the cardiac impulse, right?
Speaker: And I think it's worth kind of emphasizing physiology.
Speaker: I recall reading some years ago, the original animal studies in the, I don't know, 60s or 70s that looked at this.
Speaker: And many, many internist-based or many intensivists think about reflex tachycardia being a problem.
Speaker: But really what you're trying to modulate here is
Speaker: is the wave of propagation in the aortic artery, right?
Speaker: So it's that impulse, that delta.
Speaker: That's why it's so important to not only keep the blood pressure below 120, but also normalize the heart rate because the product of both of those determines the cardiac impulse.
Speaker: And I believe that, I mean, a lot of intensivists have to observe what you've described, which is that Esmolol does a better job with heart rate than with blood pressure.
Speaker: So sometimes you need a little bit more in terms of making sure that you're hitting both of those targets.
Speaker: But very, very important in terms of preventing further damage.
Speaker: And like you said, what we do initially has tremendous implications down the road for how those patients will fare once they leave the hospital.
Speaker: Honestly, they have a tremendous, everything you said is a 100%, and I'm glad that you stated it much better than I did.
Speaker: And then, but not only honestly on the down the road, I think if the patient's
Speaker: the hospital course well without without a without a glitch if you will mean a glitch meaning patients may have you know severe pain and require stent and stent leads to you know all sorts of complication or rupture and so on so the key initial management could prevent all that and have a kind of a smoother
Speaker: hospital course and definitely down the line will be a smoother.
Speaker: And that's really what we're observing even in the trial, it's currently ongoing.
Speaker: If you have a smoother course in the hospital, you're likely to be able to be monitored for a longer period of time without an issue.
Speaker: Perfect.
Speaker: What are some issues that you would encourage intensivists to monitor and some early warning signs that perhaps your type B dissection is becoming complicated?
Speaker: Right.
Speaker: So I think I intend to this, starting with the faculty and the staff and the APPs or the residents, is to have a low threshold
Speaker: of re-imaging, okay?
Speaker: There are certain centers that re-image in 24 to 48 hours to repeat the same CT scan to make sure everything is fine.
Speaker: But in terms of symptoms and signs, any severe pain that is despite adequate blood pressure control and the patient is still in severe pain, despite escalating doses of narcotics and the blood pressure is 110,
Speaker: So that's an issue that requires attention and proper action.
Speaker: You know, changes in the feeling of the leg and the arm and acting weird and funny.
Speaker: It's like an MI.
Speaker: I mean, if you're watching an MI and, you know, post-MI and the patient might or might not have gotten a PCI,
Speaker: and something goes wrong, patients have severe chest pain or enzyme leak or...
Speaker: or acting funny.
Speaker: I mean, funny is defined in many ways, but here in dissection, it really could be richer.
Speaker: You could think of retrograde aortic dissection.
Speaker: Patient comes in with a type B and now has a type A. So all of a sudden, their blood pressure is not staying up.
Speaker: For instance, they're hypotensive.
Speaker: That's a worrisome sign.
Speaker: Patient cannot lift their leg.
Speaker: That's a worrisome sign.
Speaker: Can a patient develop a stroke from a, let's say, carotid malperfusion from a retrograde aortic section or tear extension?
Speaker: So these are the things that you keep in mind that the disease is a fluid situation, that a disease itself could cause, could extend, despite your best effort.
Speaker: or your treatment could cause a problem despite your expertise and meticulous effort.
Speaker: So these are the two things.
Speaker: The disease itself could get worse proximally or distally or rupture.
Speaker: Or definitely if you treat it and put a sten graft in the patient or repair or, you know, has an open repair, they may not come back normal.
Speaker: I would like to dive into the treatment strategies and the current evidence for more definitive treatment, which obviously is your not only area of expertise, but I'm sure of passion.
Speaker: And this has really evolved over, I'm sure, over your career significantly.
Speaker: And like you mentioned, there's still a lot of research going on.
Speaker: But perhaps we could start, for us, with talking about the complicated type B aortic dissection.
Speaker: How do we approach that in terms of intervention?
Speaker: So just to redefine, complicated is something that patient present with a type B tear and around the aortic arch and down, and where they use mostly Stanford classification.
Speaker: And patient has evidence of hypotension.
Speaker: or malperfusion to the gut, severe abdominal pain, and you take a CT scan and it shows that the SMA is out, or a cold leg where the iliac is out, or, you know, renal failure where the creatinine is up and the kidney is out.
Speaker: So these are complicated aortic section.
Speaker: And I can say since 2000, yes, it is an area of passion.
Speaker: And it's incredible that throughout my career, actually, in vascular surgery, I saw that change drastically.
Speaker: So back in the day, patient presented with any of those that...
Speaker: that I just mentioned had almost 90% mortality because either you treat them and treating them, meaning take them to the upper room and do a laparotomy or do a thoracotomy and you cut that septum, and that aorta could never be put back together because it's tissue paper.
Speaker: Now, that by itself had a, you know, that plus the disease had next to 90% mortality.
Speaker: And that changed since the approval of Sengraft, first Sengraft 2003, and then 2013.
Speaker: In 2003, I was a fellow here in Houston.
Speaker: In 2013, I was faculty already, where 2013 Stengraft were approved for aortic section, but obviously we've been using Stengraft for aortic section way before that.
Speaker: So Stengraft essentially avoided this whole open...
Speaker: cut the septum out because you put that meticulously in the true lumen and kind of realign the aorta or push the septum back to where it belongs and seal that entry tear and the blood all of a sudden it's magic if you will all of a sudden the blood will redirect into the true lumen and the malperfusion gets resolved
Speaker: And that mortality went down from 90% to 10% in a couple of trials that were done, the stable one and stable two, which is drastically that you could think of a disease that kind of cut the mortality from 90%, 10% in our lifetime, not that many.
Speaker: So that was the – it's currently non-controversial,
Speaker: kind of first-line therapy gold standard if you will for complicated aortic section to get a thoracic endovascular repair or tvar from the start and that is that is really um considered you know this should be considered standard of care and it is it is the center of care and and in a complicated aortic dissection like this the tvar is emergent
Speaker: Yeah, T-Vor should be done within, it's like a stroke.
Speaker: It's like an MI and STEMI and PCI.
Speaker: Same thing, trauma and scoop and run.
Speaker: Same thing should be done right away, immediately.
Speaker: Time is, you know, kidney or brain or, you know, gut.
Speaker: Time is gut.
Speaker: I mean, you lose more gut by every hour.
Speaker: So it's really T-VAR should be done.
Speaker: And here I could argue T-VAR should be done expert hand because putting a stem graft may be technically not that complicated, even though it's operation for a complicated aortic section is not easy.
Speaker: It takes time, effort, and all that.
Speaker: But really the post-care, as I mentioned, you've got to put this patient in ICU that should be, this ICU should be really
Speaker: tuned in to what just transpired in the operating room.
Speaker: So that's really where the open communication and the knowledge of both teams or all the teams are important.
Speaker: Perfect.
Speaker: So like you mentioned, the evidence supports it, the dramatic improvement in outcomes.
Speaker: Are there cases where you're forced to do a surgical open approach?
Speaker: Well, if the anatomy is unfit, meaning in stent graft you've got to put a covered stent across some blood vessels and so on.
Speaker: And the limitation on that is getting less and less as technology and our skills are improving, that's not becoming an issue.
Speaker: There are one site in the U.S. that I know that does open repair anatomically unsuitable with reasonable results.
Speaker: I think for practical reasons, most, let's say here in Houston, there is...
Speaker: there's tremendous experience in open aortic repair that spans, as you said, from decades under DeBakey and Gouldy and on and on to today.
Speaker: So even in Houston, there would be hesitation to do an open repair if we can extend our T-VAR expertise in one way or the other.
Speaker: Definitely.
Speaker: Perfect.
Speaker: I shouldn't exclude it, but I definitely, I don't see much, much out there in terms of open repair for thoracic oortic dissection.
Speaker: Okay, perfect.
Speaker: Type B. What about type B uncomplicated oortic dissection?
Speaker: Right.
Speaker: And maybe the caveat there is high risk uncomplicated.
Speaker: Right.
Speaker: Right.
Speaker: So here you're talking about this is really the area of my expertise, and I spent a good decade of my life.
Speaker: I still do spend most of my waking hours thinking about it and talking about it.
Speaker: It's...
Speaker: This is currently being tested in a randomized control trial that's funded by the government, by the NIH.
Speaker: It's called the IMPROVE-AD trial, where I serve as the principal investigator along with two colleagues of mine and a team from Duke and downstate and involves 60 sites in the US and Canada.
Speaker: So this is really an ongoing research question of what we do with patients with uncomplicated tibia aortic section.
Speaker: Now, you mentioned high-risk features.
Speaker: And high-risk features, in my mind, is same as no high-risk features.
Speaker: These high-risk features, let's say, there's a list in 2020, a group of vascular surgeons came up with a list.
Speaker: based on a very thin amount of data that said in the presence of those, let's say a size of 40 millimeter or an aortic tear that is of 10 centimeter or malperfusion only, imaging only malperfusion, a few features that are based on a single study here and there that they said, okay, we
Speaker: put a StenGraft in those.
Speaker: It wasn't really well thought out at the time and still isn't.
Speaker: And most recently, the European Society of Vascular Surgery repealed all those in favor of being randomized in the trial.
Speaker: So for the New England Journal paper, actually, I initially did not mention it to one of the reviewers who wanted to have it in there, which I think is valid.
Speaker: in the sense that, okay, we have those features, we will include all those features in the trial, and then we can then validate them prospectively in a thousand patients.
Speaker: How about that for a good scientific project?
Speaker: And I think that is where we are now.
Speaker: Uncomplicated type B aortic section, they're not all equal, I give you that.
Speaker: But there are
Speaker: They're, how shall I say, the best treatment forward, if I show up today in your hospital, okay, and in the emergency department with uncomplicated type B aortic section and say aortic diameter of 40, I'm going to ask your vascular surgeon, who I know very well and I have tremendous amount of respect to,
Speaker: for is to randomize me.
Speaker: So that's essentially how it tells you how much I do not know what is the best treatment.
Speaker: And the randomization is simple.
Speaker: You either get upfront Stengraft, which like many are suggesting, meaning you show up, you get a Stengraft based on the presence of high-risk creatures or not,
Speaker: Or you get placed in the ICU and get treated the way that you usually treat the type B aortic section.
Speaker: Treat them with blood pressure medications and pills, transition to pills, and then you go home and you follow them for the rest of their lives.
Speaker: Which is better?
Speaker: I don't know, but it's definitely currently is a debate.
Speaker: Your intensivist ought to know there is a debate on that.
Speaker: And the question has not settled.
Speaker: And your team ought to be part of that investigative team that want to know the answer to it.
Speaker: to that question.
Speaker: So true equipoise and we're trying to figure out that's the focus.
Speaker: And you're part of it.
Speaker: You're part of it.
Speaker: Honestly, you're intensive.
Speaker: That's why I mentioned, I stressed the fact that ICU management will make the trial go smoothly because if your ICU management, the blood pressure is 180 every six hours in a day, then most likely this patient's
Speaker: going to have an extension of the dissection and end up with a sten graft.
Speaker: So clearly, the ICU team play a big role in making sure the patient do well.
Speaker: And getting a sten graft in the hospital is not the worst of things, obviously, but it's not necessarily the best of things.
Speaker: There's been other areas of uncertainty historically that refer to special populations.
Speaker: Could you comment on the genetically triggered thoracic ortic disease?
Speaker: You mentioned it initially as part of the epidemiology, Marfan, Ender-Danlos, and others.
Speaker: And the second population I wanted to have your opinion on was pregnancy.
Speaker: Right.
Speaker: So I'll start with the genetically triggered aortopathy.
Speaker: So they are currently, if you look up the Marfan Society website, Stengraft in the elective setting is considered to be not malpractice, but it's contraindicated.
Speaker: So meaning patients with any of the known genetic disorder, known, that's like a list of 20 or 30, 20 known, the most notable is FB1, FBN1 mutation or Marfan, and then obviously Lewis Dietz, and then Vascular, Helostanlose, and so on.
Speaker: These are, if they present with an emergency today, if it's a known or unknown diagnosis of a patient with Marfan, and again, being in Houston, you're blessed with the fact that we have the world's largest registry of Marfan syndrome at the Med Center, then it's
Speaker: If they present with an emergency, they get treated just like anyone else to save their life.
Speaker: But here's considered to be a bridge.
Speaker: So you seal the entry tear, you stop the malperfusion, you stop the rupture, and patient survives.
Speaker: you know, survive even till discharge, but you bring them back to repair or take the sten graft out and repair that segment of the aorta on the elective setting.
Speaker: That is what's considered to be the standard therapy for patients with connective tissue disorder in the acute setting.
Speaker: In the chronic setting,
Speaker: These patients are not necessarily treated with Stengraft to treat their aneurysms.
Speaker: Special caveat exists.
Speaker: I don't want to delve into it.
Speaker: It becomes a little technical.
Speaker: But, I mean, in acute setting, definitely Stengraft are life-saving.
Speaker: and you bring them back at a later date to kind of take the stem graft out and repair that aorta.
Speaker: Now, that's any of the known genetic disorder.
Speaker: You say they're a lot
Speaker: You save the life of the, you're obviously there to save the life of the patient, that is the pregnant lady.
Speaker: And if you can save the life of the fetus as well, depends on the time of presentation, when is the time presentation.
Speaker: And that could be done with endovascular means.
Speaker: There is no limitation.
Speaker: Usually for pregnancy, it's the end of the first trimester, beginning of the second trimester, where the baby is most influenced by radiation.
Speaker: But if you're doing this for an acute rupture,
Speaker: you are there to save the life of the women, of the pregnant mother.
Speaker: Now, pregnancy itself is an area where it's really women present 30-week type B aortic section.
Speaker: What do you do here?
Speaker: 37 is easy, but 30 weeks, 28 weeks pregnant and now has a type B aortic section.
Speaker: And that is really the area where I don't, I definitely think there is a very little amount of data out there or even a consensus of what to do for those patients.
Speaker: And that's why it's an area of uncertainty because it's treated very individually and duly so because we don't have that much data.
Speaker: And again, I hope it's clear.
Speaker: Yeah, and pregnancy also, the challenges of studying that patient population are well documented.
Speaker: So you don't have data, and it's likely that's the way it will remain for some time.
Speaker: Yeah, yeah, yeah.
Speaker: I mean, again, I sit on a document oversight committee for the Society of Vascular Surgery, and we were debating what are the important topics to bring as the guidelines.
Speaker: And then very pressing and important is actually a treatment of a pregnant woman with an acute aortic event.
Speaker: We have no, any vascular surgeon trying to look for this topic, you find nothing, you hit a wall.
Speaker: In terms of long-term management of T-VAR and complications, what's the recommended follow-up for patients who are discharged after a T-VAR?
Speaker: Right.
Speaker: So the guidelines say you see them at one month and you see them in your repeat imaging.
Speaker: So you see them at one month, six months, 12 months, and then yearly thereafter with a CT scan.
Speaker: At each visit, you document blood pressure.
Speaker: You ask them to have a most blood pressure, most hypertensive patients have a blood pressure.
Speaker: Many hypertensive patients have a diary or a table of their blood pressure control.
Speaker: So you obviously try to go over that with them and highlight any areas where the blood pressure could be improved.
Speaker: So that is the regimen and that is where a partnership with a cardiologist that also has an interest in aortic disease is important and important.
Speaker: you know, you follow them as a vascular surgery, you follow them for aneurysmal growth, essentially, that's the most important thing.
Speaker: And when they reach threshold, given over a period of time of repair, you then take them for a repair of their aortic aneurysm.
Speaker: And that varies from, it depends on age and presentation and so on.
Speaker: So that
Speaker: We were talking before we started recording that a common transfer reason is somebody presents to an ED and they have pain or other symptoms.
Speaker: They get a CTA and these are patients who already had a T-VAR and they see things that are interpreted as abnormal and they get transferred to a vascular referral center.
Speaker: What are the true emergencies post-T-VAR that we should be aware of?
Speaker: So...
Speaker: uh that's so i can feel your uh it's funny when you get when you when you get a call all patient has a t-var call and ask a surgeon and this fast surgeon looks at it is like okay well send the patient back but which is nine out of ten times probably the case however
Speaker: There are definitely emergencies post-TVAR, post-immediate implantation or years even, years later.
Speaker: You can think of the, and it depends also on the age of the patient and the risk factors and whether hypertension or not plays a role.
Speaker: Now, you can think of the StenGraft as a rigid implant.
Speaker: rigid material sitting in the aorta that is moving.
Speaker: So you can imagine the forces, and it depends on if you put it top of the candy cane or in the straight portion of the candy cane or in the curve of that candy cane, these forces are going to hit the stingraft and cause all kinds of issues.
Speaker: Now, the issues can happen,
Speaker: In the true emergencies, that jet of blood with the systolic blood pressure hit the proximal part in that candy cane portion of the aorta and lead to a new dissection that goes in a retrograde fashion into the heart.
Speaker: So retrograde aortic dissection is directly related to the size of the stingraft and the fact that
Speaker: uncontrolled hypertension, you'll end up with a real disaster here by retrograde aortic section and causing a patient to have a type A. So, all of a sudden, patient has no cardiac output if it's in the operating room or, you know, could come a later date with a new chest pain or so on.
Speaker: So, similarly, could happen in the distal portion of the aorta and cause
Speaker: what's called a distal single new entry tear or D or SINE and stent induced a new entry S-I-N-E and that could cause
Speaker: a new type B aortic section could be with malperfusion.
Speaker: You put a sten graft in and you're high-fiving and you're good and the patient two days later has no flow and lactate goes up to 10 in the ICU.
Speaker: And that is because your sten graft actually caused a new tear that led to malperfusion.
Speaker: So immediately you could have a new dissection, proximally or distally,
Speaker: And that, or could, you know, these are the immediate complication that are true emergencies.
Speaker: I think that was your question.
Speaker: Yes.
Speaker: True emergencies.
Speaker: Over a long period of time, I mean, Stencratt could migrate, the aorta could dilate, and still have an aneurysm.
Speaker: But these are more chronic elective repairs that could be addressed on follow-up.
Speaker: But true.
Speaker: true emergencies really could happen in the ICU.
Speaker: I'm talking retrograde dissection or new entry tear is definitely on the top of the list.
Speaker: Perfect.
Speaker: As we close for us, what would you as a vascular surgeon want your ICU colleagues to know and to do?
Speaker: And we mentioned a lot of it throughout the conversation, but in terms of kind of a wrap up and summary.
Speaker: Yeah.
Speaker: Right.
Speaker: Everything I mentioned, but honestly, I would love it if ICU team develop into, if anyone, if you can have a dedicated aortic disease.
Speaker: team, and that includes the ICU team, to understand that aortic dissection is, I want them to know that aortic dissection is changing in terms of therapy.
Speaker: Blood pressure control in the ICU is of blood pressure and heart rate control is so important for the patient outcome.
Speaker: Open communication and taking ownership of the patient as much as the surgeon is key.
Speaker: And then low thresholds really for re-imaging.
Speaker: I mean, of course, you're talking to your surgeon or surgical team and so on.
Speaker: But recognizing, you know, these changes in patient labs or presentations and so on are important to trigger, you know, re-imaging or direct communication with the surgeon to consider...
Speaker: something new happened.
Speaker: That's really important in terms of, but if I want to give something to the intensivist and the nurses and the APPs and so on, is to, I cannot overemphasize the critical role of initial blood pressure management with the appropriate agents.
Speaker: Yeah.
Speaker: Perfect.
Speaker: Ross, we'd like to close the podcast with a couple of questions that are unrelated to the clinical topic.
Speaker: Would that be okay?
Speaker: I mean, I'll try.
Speaker: I don't know anything outside of the orientation, but yeah.
Speaker: We'll give it a shot.
Speaker: Perfect.
Speaker: Is there a book or are there any books that have influenced you significantly or a book that you have gifted often to other people?
Speaker: So I gifted something else with the books that I read many years ago.
Speaker: There's a book that my wife handed to me, and I think that was a beautiful read.
Speaker: We still remember it many years later.
Speaker: It's called A Dangerous Liaison.
Speaker: It's by Carol Seymour Jones.
Speaker: It's about the story...
Speaker: are the lives of Jean-Paul Sartre and Simone de Beauvoir.
Speaker: They're the two existentialist philosophers that lived for the 20th century in France.
Speaker: And it's a beautiful read for...
Speaker: I think for me, it resonated so much in terms of depth of living and so on.
Speaker: And then, you know, it's from a beautiful era in Paris.
Speaker: So why wouldn't you love that?
Speaker: It was a very, a book influenced me.
Speaker: You know, I do like history books as well, but that's probably dear to my heart.
Speaker: A book I gift more than others is,
Speaker: Very relevant to what I do and what we just discussed is A Time for All Things by Greg Walker.
Speaker: It's a book about the history of Baylor College of Medicine and Michael DeBakey and all that, which I think, given that all my friends are vascular cardiac surgeons or cardiologists or intensives, they find it helpful or useful, whether they're in it or not.
Speaker: These are the two books.
Speaker: Perfect.
Speaker: Could you share with us something you changed your mind about over the last few years?
Speaker: So I worked in, I had the privilege of working at the Imperial College in 2021-22.
Speaker: Still, as you mentioned, I'm part of the faculty and working in the NHS in England,
Speaker: It was an outstanding, amazing experience.
Speaker: Because many people tell you, so which is better, right?
Speaker: Because as if it's like, I'm going to put a number on it.
Speaker: And it's honestly, I'll give you an example.
Speaker: shows up in the emergency department with a diabetic foot ulcer and in the US we spend you know we we take the patient the next day we do a bypass and so on and the patient may lose their leg right very possible within within but within 10 days a patient would have had a would have had a problem solved one way or the other in England this patient will spend a good month in the hospital may or may not you know
Speaker: Actually, in the U.S., we would save their leg, but 10 days in the hospital, gets a bypass, goes home, but end up with a bill of $5,000, for instance, let's say.
Speaker: In England, they may spend a month in the hospital, and they may lose their leg.
Speaker: There's a good chance, and they end up with a BKA, but guess what?
Speaker: It's free, right?
Speaker: So a patient, you ask as a patient, one is stuck with a $5,000 bill, and one is free, right?
Speaker: So which is happier?
Speaker: Because maybe you and I could pay a $5,000 bill, but not average, not most patients cannot, right?
Speaker: Right.
Speaker: So, so that led me to think is like, you cannot say which is better and you lost a leg guaranteed.
Speaker: And this guy that had a bypass may lose their leg eventually, but it changed my life in the sense of like, there's so much the things that we take, what we do and we think, you know, in our daily life that, that is totally different from, you go to a different country or even different hospital or different state.
Speaker: So that's my cynical way of actually how I change my views in medicine in general, to be honest.
Speaker: And I think different experiences provide different perspectives, but also at the end of the day, it's also why there's so much difference ideologically today in the United States is not because the other side of what you think or people feel different are wrong.
Speaker: It's just that they value different things.
Speaker: Yeah, totally.
Speaker: Totally.
Speaker: What you value and what you choose to solve for because you can't solve for everything, right, determines a lot of those impacts.
Speaker: But I do believe that I agree and it makes a lot of sense.
Speaker: And the final question is, what would you want every listener to know could be a departing thought, even a quote that you want to share with us?
Speaker: Well, that's a good one because I actually struggle to come up with –
Speaker: over the years, maybe as I get older, you become more and more cynical of everything around you or just me.
Speaker: I think a code or a fact, I think it's hardly no one knows.
Speaker: I mean, I guess you could say...
Speaker: no one cares to know the truth kind of thing because, I mean, the truth could be a lot of things that you may or may not want to know.
Speaker: So that's it.
Speaker: And for us, I want to thank you for your generosity with your expertise and your time.
Speaker: We'd definitely love to have you back for another conversation on vascular emergencies.
Speaker: We'll keep track of the ongoing trial with the uncomplicated patients.
Speaker: type B dissections and see when that comes out.
Speaker: But again, thank you.
Speaker: Thank you very much for being on with us.
Speaker: Thank you.
Speaker: Thank you, Sergio.
Speaker: It's a great honor.
Speaker: Thank you.
Speaker: It's a great day.
Speaker: Thank you.
Speaker: Thank you for listening to Critical Matters, a sound podcast.
Speaker: Make sure to subscribe to Critical Matters on Apple or Google Podcasts and share with your network.
Speaker: Sound's transforming the way critical care is provided in hospitals across the country.
Speaker: To learn more, visit www.soundphysicians.com.
