Latest / Behind The Knife: The Surgery Podcast / Clinical Challenges in Vascular Surgery: Asymptomatic Carotid Artery Stenosis
Transcript
- CarotidStenosisBTK === [00:00:00] Okay, welcome to Behind the Knife, clinical Challenges and Vascular Surgery. I'm Andrew Wong from the University of Michigan. I have with me here Frank Davis. Uh, Robert EU and Luciano del Bono. And today we're addressing asymptomatic carotid artery stenosis. So for decades, a tight carotid stenosis felt like a ticking time bomb, like a plaque that's weighing to throw an ems. And cause a stroke. For years, physicians were taught that severe narrowing meant surgery with numerous trials such as the ACAS trial, the A CST one, demonstrating the benefits of intervention. However, medicine has changed in the decades since with numerous new medications such as statins, antiplatelets, different blood control agents, and PCSK nine, as well as glp. The one therapies have quietly slashed stroke risk, and now even newer data from the CREST two trials has introduced new questions on how to care for asymptomatic disease. Therefore, if modern therapy works better than ever, who actually [00:01:00] benefits from an intervention and who needs an intervention? And today we're gonna go over the evidence, the controversies, and the approach to a patient who maybe may feel fine, but has a high grade stenosis in clinic. So the first discussion question is, why does the management of asymptomatic carotid stenosis remain so controversial? Yeah, thanks Andrew. So I'll take this one. So the old landscape. With some of the older RCTs showed that CA clearly reduced stroker risk versus medical therapy alone in both asymptomatic and symptomatic stenosis patients. Some of the older estimates using the A CAS, the NASA, and the A CST demonstrated a 2% stroke per year in high grade asymptomatic carotid disease with an absolute risk reduction of about 5% with CEA plus optimal me medical therapy versus optical medical therapy alone with about a 50% stroke presented. Prevented. At five years per 1000 cas. [00:02:00] This led to the s, the SVS and a HA guideline recommendations for treating high grade asymptomatic carotid stenosis in those patients. However, CREST two is a trial that has come out recently that has thrown some controversy in these statements. Uh, but we'll kind of go over those at a later time. So Bobby, do you want to kind of lead us into some of the optical medical management? How. That sort of changed the landscape. Yeah, totally. Because I think understanding the medical management realm of this really helps explain a lot of the controversy. What we were originally seeing is that when most of these trials came out, that touted the benefit of asymptomatic carotid interventions. It was really aspirin. So anti-platelet therapy with aspirin was the mainstay of our treatment regimen, but this has really changed recently. And the addition of some of these newer agents, including some of the follow-up trials, which have demonstrated low stroke risk amongst the cardiovascular outcomes used to get these patients or these [00:03:00] medications approved, really has brought into question whether or not these are better than our previous medical treatment strategies, and therefore, throw into doubt some of the comparisons. With some of our intervention arms before, so let's just talk about sort of the standard of care medical therapy. As we've talked about, anti-platelet therapy is one of the mainstays of reducing the risk of TIA and stroke in patients with asymptomatic carotid disease. And asymptomatic carotid disease is typically managed with 81 milligrams of aspirin daily. Some of this is based on the. Antithrombotic Driverless collaborative, which showed the combined cardiovascular risk reduction was the highest amongst patients who are on aspirin, 81 compared to any other dose. So you don't really need to have these patients on 3 25 of aspirin. Some have wondered, well, what about the addition of clopidogrel? So you're on dual antiplatelet therapy with aspirin and clore. And for a while it was thought that maybe adding these to the very highest risk of patients might be the the way to go. [00:04:00] So those patients with 75% and above, but not occluded, might benefit the most. And really the charisma trial, which looked at the use of dual therapy for a number of vascular indications, didn't really show much of a benefit. There's probably one group that benefits from the dual anti therapy the most, and we're gonna talk about this outside of the intervention arm, and that's those that have had a recent TIA based on the chance trial. So in that trial they started patients on clopidogrel plus aspirin within 24 hours of their minor symptoms and found a significantly reduced stroke risk at 90 days. So that's not really within the purview of our discussion of asymptomatic disease, but it's probably one of those things that's just really good to know. There are other elements of, uh, appropriate medical therapy, and that includes being on a statin and really high intensity statin. The a HA and SVS define high intensity statin pretty strictly, so that's patients who are younger than 75. That's either Atorvastatin or Rosuvastatin, so that's Lipitor. [00:05:00] Crestor at 80 milligrams or 40 milligrams respectively. If they're older than 75, you can drop that dose down to 40 milligrams of atorvastatin and. 20 milligrams of Rosuvastatin, and that's considered high intensity therapy. It's also aggressive blood pressure management, and I think that that's probably a staple of therapy for most of our patients, regardless of their carotid status. But really, we're talking blood pressure in the one 30 to 1 35 range and below. Seems to have the best risk reduction you want to target in glucose. Um, a target A1C of less than 7%, and the GLP ones have really moved the needle on being able to accomplish that with either injectable or oral agents pretty well despite, you know, that being a really hard target for a lot of people for a. And then there's the sort of standard things that you should counsel all your patients about, including smoking cessation, exercise, and um, weight loss strategies. And I think this really is a nice segue into some of those newer agents because the weight loss [00:06:00] and the diabetic control are really well accomplished with the GLP one the GLP one agonist Now. And what we found is that those have been demonstrated to have an overall cardiovascular risk reduction and hasn't been specifically studied in, in carotid disease, but we have seen in patients where the outcome is a combined one that includes stroke, that it seems to be a pretty low risk. So there's a lot of patients who have. Gone on that and noticed a benefit, though I wouldn't say that's standard of care for doing that. For asymptomatic high grade carotid disease, PCSK nine inhibitors. You're thinking like the evolocumab and path and stuff. Those ones are pretty widely accepted in clinic now, and what we've seen is those reduce your LDL. By typically 30 points on average. So really helpful for not only those recalcitrant patients who are on statin but can't get below that 70 mark that we shoot for for asymptomatic high grade disease. But um, so not only those patients, but also ones who just can't tolerate statins, they seem to do really well.[00:07:00] With these PCSK nine inhibitors and there's a few RCTs that have looked, not specifically just at at carotid disease, including like the Odyssey trial and the four year trial, and shown that they've reduced cardiovascular events as well. So I mean, I think that the medical therapy really has improved, and this has probably been the biggest element that's led medical physicians to say. Hey, should we be intervening on this at all? Because I'm seeing such an improvement with the addition of these modern agents. And so I think before we can sort of say yay or nay, we need to get into a better understanding of what interventions we're even talking about. Yeah. Thanks Bobby. And I think that's a really good summary of what is considered optimal and best practice medical management in the current day and era. Um, for patients with asymptomatic carotid disease and indeed patients who come into your surgery clinic, it's really important that the first thing you have to do is optimize their medical therapy. But even after optimizing their medical therapy, I think let's get a good understanding of the different surgical options for patients with asymptomatic carotid [00:08:00] disease. Now, Andrew, I know in the, in the past there's been a number of car trials that looked at asymptomatic carotid artery. Um, disease and looked at surgical therapy versus optimal medical management. Do you mind kind of touch base upon what those trials are and what they showed? Yeah, so one of the first trials for this was the A CAS trial, and this was the one performed in North America. This went from 1987 to 1994, so a long time ago, but enrolled 1600 patients with an who are asymptomatic with a greater than 60% stenosis. The endpoint for this study was a five year stroke or death. There was a rate of 5% with CEA versus 11% with medical therapy. However, it's notable that there was a perioperative stroke and death rate of 2.3%. Yeah, that's a really good point because in acas, the way they proved that you actually had the degree of stenosis you said you did, is they did cerebral angiograms on almost everybody, and there is about a 1% stroke risk from the cerebral angiogram alone. So I mean, I think that's a real big red flag with that trial, but it has [00:09:00] been what we've looked at the most. Yeah. And then this was, this trial was also performed in acs, T one over in Europe. This went from 1993 to 2003. This was a large trial, rolled three over 3000 patients, similar with an asymptomatic greater than 60% with an end, uh, with an endpoint of five year stroke or death. And it showed similar results with 6.4% stroke or death in CEA versus 11.8%. For medical management. Most importantly, it showed that there was a durable benefit of CEA at 10 years with a 10 year stroke risk of 13.4% in the CEA cohort that was lower than the 17.9% in the medical management cohort. Notably also, there was a 3% perioperative stroke risk of stroke or death in this study. Main limitations for this. You know, these studies were at least 30, 40 years old at this point. And fewer than 40% of these patients received statins. It was not part of the clinical standard of care at this time. Much of the benefits that [00:10:00] were demonstrated were mostly in men. Since only 34% were women and demonstrated no clear benefit of these patients. Thanks Andrew. I think that's a, a really good summary of the two major trials that looked at more historical, but carotid endive versus optical medical therapy. Um, I think it's important that we also touch upon, there's other trials 'cause carotid ectomy is not the only surgical option for asymptomatic carotid disease. Indeed, we have carotid artery stenting or transfemoral carotid artery stenting. And, and now more recently we have TAR from that option. So let's go over the trials for carotid artery endarterectomy versus carotid artery stenting. So the kind of the, the tried and true trial that compared carotid endarterectomy versus carotid artery stenting was crest one. And later on we're gonna talk about crest two, but the crest one trial. Was a randomized controlled trial, again, comparing carotid artery stenting to carotid endarterectomy in symptomatic and asymptomatic disease patients. The findings of this trial demonstrated there was no significant difference in primary composite outcome, so that, [00:11:00] again, that's a combination outcome of stroke, mi periprocedural death, or periprocedural stroke. Indeed. However, they did find that the periprocedural stroke of carotid artery stenting was higher at 4.1% compared to 2.3% in the carotid end ectomy group. However, the Periprocedural MI rate was higher in the carotid ectomy trial or carotid end ectomy patient, excuse me, at 2.3% versus 1.1%. Overall, I think Crest one is an important trial because it had. 10 year follow-up that showed no significant difference in primary composite endpoint of carotid artery stenting or carotid end ectomy. So in summary, you kind of have equivalent long-term benefits of carotid artery stenting and carotid ectomy for patients with asymptomatic disease, but you do have different peri procedural risk of either stroke or mi, depending on the operation pursuit. Yeah, dude, I think that's a very important point to bring up because that was probably one of the biggest criticisms when CREST one came out, that this combined composite endpoint of stroke death in mi. Was equal between the two. [00:12:00] But in carotid, endar, ectomy patients, you had more mis and in, uh, carotid artery enting patients, you had more stroke and didn't sit right with a lot of people that you're doing a procedure to prevent stroke and you had a higher risk of, of causing a stroke. And so I think that was one of the things that. Really made people feel like these composite endpoints didn't tell the whole story. And I think that's probably something we'll get into when we talk about Crest two too. Yeah, very good point, Bobby and I truly agree with that. In my clinical practice when I talk to patients like on Crest one, another port thing is the MI para procedure mi. They were looking for troponin elevations, which is a mild troponin elevation, classified as a paraprocedural MI compared to a full on stroke or different patient. Outcomes and how a patient experiences that outcome. So I think that was another one of the criticisms I remember heavily talking about when Crest one rolled out. I think the other trial that's kind of come out most recently looking at another operation to repair asymptomatic carotid artery disease, I think is important to highlight is the Roadster two trial. And this trial was a prospective [00:13:00] industry-sponsored single arm multi-centered study, specifically analyzing patients to undergo TCAR. Um, this trial analyzed 166 patients who were deemed too high risk for carotid ectomy. 43% had what we deemed high risk anatomical features, and that's typically considered either a high lesion radiation recurrence stenosis despite carotid ectomy before. And the Roadster two trial found. 77% were asymptomatic with no strokes reported after the trial. And the Roadster two trial was really the trial that put TCAR one of the more common operations now for asymptomatic disease on the map. And I think that's important. We, we address here today because TCAR is a relatively common surgery that occurs in patients with asymptomatic disease. So Frank, what do you think is the difference between carotid artery stenting and TAR? Yeah. Like why does TAR have a better outcome? Yeah, no, great question. So I think, um, when you think about carotid artery stenting, that's typically classically referred to as trans femoral carotid artery stenting. Um, whereas [00:14:00] TAR you access the carotid artery right above the clavicle, it's a higher level. So just for individuals on, on the. Podcaster out on that call who haven't really done these procedures before. In transfemoral carotid artery stenting, typically you involve a distal embolic protection device that passes the area of significant stenosis in the carotid artery. As such, transfemoral carotid artery stenting typically has a higher peri procedural stroke risk. And indeed, that was shown in Crest one trial. However, TAR is different. The fundamental technique of TAR is different in terms of it involves reversal of flow. So you temporarily clamp the carotid artery, prevent antegrade, flow up the carotid artery, and allow reversal flow. As such, the stroke risk for TCAR is typically reported as less than transfemoral carotid artery stenting in that aspect. So technically the procedures. Although both end result of placing a stent in the carotid artery, how you get there and how you go about doing the procedure are fundamentally different. Good question, Luciana. So, but now I think we get to kind of the crux of this [00:15:00] whole podcast, which I think is really important, not only for us, but the global vascular surgeons across the country. Talk about the Crest two trial, 'cause that's the most recent trial that came out and really kind of throw some wrenches in the, in the system about how we manage asymptomatic disease. So. Luciana, why? Why don't you talk a little bit about Crest two in terms of its design and kind of what, what is it most recently found? Yeah, so Crest two is what we all came here for. So the main question in Crest two was does adding carotid and carotid endarterectomy versus carotid stenting to intensive modern medical therapy help prevent stroke more than medical therapy? An ASIC symptomatic high grade stenosis. So the design was two independent parallel arms with their own medical therapy groups, which is, that in itself is important. So they had carotid artery, um, stenting plus medical therapy versus medical therapy. That was one arm, and the second arm was. Carotid endarterectomy and medical therapy versus a medical therapy. Yeah, that's a totally important point because unlike Crest one, they didn't [00:16:00] compare endarterectomy to carotid artery stenting. This was endarterectomy versus medical therapy or stenting versus medical therapy, but not the two intervention arms against each other. Right. And the patients in this study were high grade asymptomatic chronic stenosis, so they had to have. A greater than 70%, um, stenosis, no disabling stroke, and had to all be eligible for either a carotid endarterectomy or a carotid stenting and all got the best their, their medical therapy. Um, so some of the key findings for this study, so the stroke risk in the medical group was much lower than in past trials. So in this, it was about one to 1.5% per year versus the typically quoted two to 3% per year pre statins. For the stenting trial arm, it was a four year incidence of primary composite outcome of perioperative stroke or death through 44 days, or ipsilateral ischemic stroke thereafter was about [00:17:00] 2.8% in the crowded stenting versus 6% in the optical medical therapy. Yeah, I, that's another one of those good points. Sorry to keep chiming in, but you know, this is like that composite output outcome question that we talked about with Crest one. So it's interesting perioperative stroke or death through 44 days. I mean, how would you compare that to medical therapy? You know what I mean? Like you're just within 44 days, clearly you have a little bit more of a risk when you undergo a procedure that you're gonna have something peri procedurally, and so you. I think it's pretty impressive that carotid artery stenting still demonstrated a significantly improved benefit, when really it's getting penalized up front and then having to make it up on the back end, which was the remainder of the four year follow up looking at the, the stroke risk. So, uh, it's one of those things you just gotta really read into what these composite outcomes actually mean. Right? Totally. Okay, so now for the endarterectomy group. The four year incidence of the primary composite outcome was 3.7% [00:18:00] versus 5.3% in the optical medical therapy group, which was not statistically significant. It's important to note, though, that CREST two was not designed to test CEA versus carotid stenting, which we've mentioned, but optical medical therapy versus revascularization, and it showed that revascularization works. So revascularization works, but the absolute benefit is much smaller than 20 years ago. So with these findings, what were some of the limitations of this trial? Yeah, so many. Uh, I think one thing that's important to remember here is that many of these limitations there for this trial are just intrinsic to clinical trials in general, it's not perfect and it's not possible to achieve that typically, but one, some of the limitations are OMT in the medical arms. It was to such a stringent degree that it's difficult and challenging to replicate in the real world, such as actually hitting an LDL of 70 of these patients. Secondly was the degree was the number of cases that the interventionalists had to submit in that the interventionalists had to [00:19:00] do a hundred, um, transfemoral carotid artery stenting with at least 25 cases performed in the past year with only 50% of applicants accepted. Um, surgeons on the CEA arm, however, had to submit only 50, so half the number of OP noes, and this was over any time period with a 90% acceptance rate. Yeah, it's super important to note, 'cause I mean, Frank, I don't wanna speak for you, but I think Crest two really bumped down, or Crest one, sorry, really bumped down the number of carotid artery stents that I did. Mm-hmm. I'd say performing this many within the past year would be hard for most practitioners. You'd have to be really cranking 'em out to be able to get this many on there. So that's a, that's a real limitation. You have to ask yourself, are you the type of person performing the studies or the interventions in this study? And do your outcomes for when you do it, replicate what they saw here before. You can interpret whether or not you can compare that to medical therapy in your patient. Yeah, a hundred percent agree. Transfemoral carotid artery stenting after crest one did [00:20:00] semi drop in practice and the number of people across the country perform this number of procedures for transfemoral. Carotid artery stenting is a limited, and they do, when they do a lot, they develop a technical as. Expertise at it. So it can't be globally applied to all practitioners within the country. Yeah. So another component here is just a degree of disease in the, that we're able to be Ted. So stented lesions needed to be less than two centimeters long. Circum mineral calcification was, and, uh, was ruled out for these patients, and they could not have any unfavorable anatomy or disease in the inflow vessels, which was determined by the operator, such as a type three aortic arch. Another limitation here was the, um, two separate medical arm. Arms overall, the incidence rate of stroke were different between the two arms. Um, such as 6% risk of stroke and death in the transfemoral car artery stenting arm at four years versus 5.2% in the surgical arm. Yeah, some people [00:21:00] have wondered if that made it underpowered to be able to detect a difference in endarterectomy. 'cause you know, they didn't see a difference in endarterectomy versus optical medical therapy significantly. But percentage wise, I mean, it was a pretty decent difference. And you know, I know there's liars, Dan wires and statisticians, but at the end of the day you wonder if. The power is really what made carotid ectomy not have as favorable of a look as carotid artery enting did. Yeah. I'm sure we're looking forward to all the subsequent follow up studies there to follow with this. Yeah. Good. It's a gold mine. Yeah. Yeah. So next up is the, there was a 20 oh greater than 20% crossover between the medical and intervention groups with each arm. So with the intention to treat analysis that they went that they had, this is intrinsic to most, many clinical trials. An important thing here is the follow-up timeframes. They were different between carotid artery stenting as well as a CE, A cohort that the CEAs had additional year follow up convers the transfemoral carotid artery stenting, given that there was suspended [00:22:00] recruitment for a period of time for the carotid stenting. And importantly in the CEA cohort, in the final year of follow up, there were a high, there was a high incidence of follow-up events which resulted in, um, the, uh, inferior outcomes, whether or not this would've happened with carotid artery stenting is unclear, but they'd had a shorter period of follow up there. Um, and finally. This study didn't include TCAR, which is a very common procedure now as the modality for stenting for these patients. Especially when you take into account the learning curve that's involved with TCAR compared to transfemoral, carotid artery stenting. There are numerous studies out there evaluating, um, how do. Physicians handle that learning curve. And how many cases does it take with transferor carotid artery stenting, it's typically 50 to a hundred cases. With TAR, it could be lower as low as 30 cases or so. Okay. And given that there are concerns, as we discussed previously, that perhaps less experienced [00:23:00] practitioner practitioners who really aren't hitting the numbers to meet Crest two inclusion, like we discussed earlier, might be attempting carotid artery stenting and not be making the, having the favorable outcomes that were demonstrated in this trial. Yeah, I mean, for me, that kind of pushes it. To be even a little bit more impressive. I mean, 'cause TAR has a lower stroke incidence than most trials that have looked at transfemoral carotid artery stenting. Now they haven't been compared directly, but when you look at Roadster results, it's, you know, between one and 2%. What we would traditionally actually quote for endarterectomy. That being said, you know, TCAR wasn't included, but still carotid artery stenting did better. So that learning curve that you're talking about probably played into why carotid artery stenting looked so good here. I do wonder though, if you had included TAR, would it have looked even better? Mm-hmm, mm-hmm. Great point. Yeah. So talking about some of the clinical significance of the trial. Right? So this is the first trial that shows that carotid stenting plus intensive medical management beats medical management alone in asymptomatic [00:24:00] patients. The decision is individualized though, right? So you have to take into account. The patient age, their surgical risk, their life expectancy, the plaque morphology, and the patient preference. But sort of based on the limitations of this trials, it's difficult to incorporate these findings into the clinical practice. So Bobby and Frank say that we have a patient who comes into your clinic with high grade asymptomatic carotid stenosis. Sort of can you walk us through first how you just work that up and what you would offer this patient? Yeah, so I mean, I think it's, as you mentioned before, for the decision to get really individualized, right? So you have to consider the patient their risk factors. Are they advanced age not gonna meet that five year life expectancy that you'd expect for asymptomatic carotid disease? Do they have a number of other cardiovascular comorbidities that would prevent them from reaching the long-term benefit of a surgical operation? First and foremost, for all patients who walk into my clinic, I think this trial. A Crest two has shown that they need to be on optimal medical therapy, and that's, as [00:25:00] Bobby already pointed out with a great discussion of medical therapy, is you need to optimize their statins, their antiplatelet therapy, their glucose levels, their hypertension, and their smoking sensation. So that needs to be first and foremost 'cause that has been shown to significantly decrease the risk of stroke. Even compared to 20 years ago for patients who are optimized and do have a relatively long life expectancy, when you talk about asymptomatic high grade carotid stenosis, I consider operating an operative intervention for carotid ectomy or carotid artery stenting. However, prior to doing that. I typically get a CTA of their head and neck to evaluate the the plaque morphology in the carotid artery. So is it a highly calcified plaque? Is it a ulcerated plaque? How high is the lesion? Those aspects, 'cause that typically would push me one way or another for a carotid ectomy. Versus a T car is typically my practice for carotid artery stenting. So that's kinda how I work with the patient and talk councilman on that way. Yeah, I think that's important to mention too, because in Crest two, this trial that we've been talking about, they didn't do anything beyond plaque [00:26:00] degree of stenosis. There was no morphology characteristics, and a lot of us will look at whether or not it looks like an ulcerated plaque by duplex ultrasound, or by ct. We'll look at some of the plaque anatomic characteristics to say whether or not this patient should get intervened on. So I totally think that's a, a very smart point that you end up having to bring up that most of these patients will get a confirmatory study with, uh, with a CT scan. Yeah. Yeah. I think the, you know, overall. Thing is there's a little bit of like a Rorschach type thing. Before people were looking at whatever they, when they saw the old trials and they were saying, well, I don't know if I want to intervene as much, and those who are more comfortable with medical therapy or couldn't do surgical intervention, they felt like the trials didn't apply because we have all these new modern. Medical interventions like the PCSK nines. The GLP statins, I mean, doesn't even seem that new, but statins and what I think people were hoping for though is with this trial, we would get a much more definitive answer and [00:27:00] dare say that some people were hoping there would be a non-inferiority 'cause it would prove that the medical therapy had really advanced. When I look at this, I tell people, you're in the most, you're amongst one of the most studied group of patients that we have right now because this is such a gray area problem. It's in incredibly critical, like Frank mentioned, that you're on medical therapy because just the advances in medical therapy alone have lowered this stroke risk. I mean, I had a patient in clinic recently who's. 80 still working. I don't know what that says about our social safety net programs, but 80 is still working and said, wait, so my stroke risk at four years is 6% with medical management therapy. Or if you do a carotid artery stent, you know it's a little bit less than 3%, and if you do a carotid ectomy, it's a little bit over 3%. He said 6% doesn't sound that high to me if all I have to do is take some medications. Whereas in the past, our conversation with that patient would've had to been, Hey, your stroke risk is 10%. Or you know, as you talked about, the [00:28:00] 10 year follow up data for acas up to 17.9%. So, I mean, I really do think that this is, if you're, you need to have your patients on medical therapy and then. I'd say it doesn't answer the question about TAR at all. I'm, I'm still doing TAR in patients and I tend to look at this as maybe just underpowered or some of those limitations driving the non-inferiority in the CEA group. And I tend to say for most of my high grade. Asymptomatic patients who are on medical therapy have maximized lifestyle changes and have a life expectancy that exceeds three to five years, that, yeah, we should really consider an intervention and we lay out the numbers and if it makes sense to them, it makes sense to me. What about a patient, let's say 92 years old, but they have the eye of the tiger. They play golf every day and you know, they otherwise have no other medical conditions. Yeah, I, I mean, I, I think what you're getting at is, you know, these are a little bit older patients. We don't do a great job at looking at actuarial data to say what your survival is gonna be, and so.[00:29:00] What you do have to do is treat that patient that's right in front of you. If they're a functionally active patient, then I tend to get a little bit more aggressive about intervening for them, provided that they, they understand what we're, what we're talking about here. Because you do buy some of the risk upfront when you do an intervention. It's like we talked about with the Crest two results where that four four day periprocedural stroke risk and, and death risk was. Was one of the metrics. And, and so you are doing something to them that can cause an issue. And some people have a really big problem with the feeling like they did something that then caused 'em an issue. And some people are like, Hey, it's gonna be what it's gonna be at 92. Yeah. And I, I think it. As, as much as a, there's a health quote, unquote healthy, 92-year-old, one of my former mentors said a surgeon. Our patients always show their age under surgery. Mm-hmm. So like even the healthiest 92-year-old is still 92, right? Yeah. So you just have to, uh, be cognizant of optimizing their medical therapy, making sure they understand the risks, and like you talked about your patient before the 80-year-old who said, wait 6% is not that bad. [00:30:00] When I'm 80 or when I'm 92. And they might choose that and that's fine, but you have to optimize their understanding of what each condition offers them. Alright, it's been a great discussion. Thank you Frank Bobby Looch for participating today and discussing carotid, asymptomatic carotid management and as always dominate the CEA. What dude dominate the day and go blue.