 Welcome to Texas Heart Institute Educational Series. The topic of this particular program is breaking the barrier in cardiac and vascular interventions. I'm your host. My name is Von Merkrager. I'm peripheral vascular intervention program director in Department of Cardiology at Texas Heart Institute and also president of the International Society of Endovascular Specialists. Our special guest today is Dr. Miguel Montero Baker. He is an associate clinical chief in division of vascular surgery and endovascular therapy at Baylor St. Luke's Medical Center. It's a true honor, sir, to be here. Thank you. This is the second time and hopefully many more to come. It's a pleasure to be here with you today. Thank you very much. So I would like to start this program with asking you several very important and pertinent questions related to diagnosis and treatment of peripheral arterial disease of the lower extremities. Let's concentrate on the particular important questions related to that particular topic. And let's mention past, present, and future of surgical and endovascular treatment of peripheral arterial disease of the lower extremities. But also I would like to hear from you specifics related to the unmet needs and also the aspects of how has vascular surgery evolved over a period of the last few decades. So let's start with the question of task classification, how it has evolved, where we are now, and how often do you use it in your practice? Very well. Thank you, Dr. Kreiser. So task refers to the Transatlantic Society consensus. It was an attempt to try to get a lot of professional groups across the global scenario on the same page. And there was a series of publications, one focused mainly on the risk and the medical management of a lot of these patients, and then one more attempting to go deep into the more technical part. Now the task, an attempt to give some form, the task group created anatomical degree of classifications. And actually, as you can see on this slide on the right-hand side specifically on the aorta iliac system, they went on to classify patients within four groups, A, B, C, and D. That then went on to be done also for the femoral papatil and for the below the knee disease. Now if you specifically go into the aorta iliac disease, one of the things that had for many years raised some eyebrows or at least created discussion around the topic was that this is the C and the D patterns of disease. And what the consensus hints to is that all these patients are better served with open vascular repairs. Now that's easy said, not necessarily easy done, specifically because of the risk patterns of patients. One would then argue that there are extra anatomic bypasses that are made in a way to meet the needs of maybe the high risk surgical patients because most of these open repairs would actually imply that the patient would need a laparotomy. And not a lot of these patients can actually undergo a cross-clamping of the aorta safely. And not a lot of these can actually bounce back quickly, specifically the more frail patients. Now this is an image of one of my actual patients. This is a bypass from the subclavian to both common femurals. And that's an extra anatomic bypass, which some authors actually argue that could be even done under local anesthesia for high risk patients. Now sadly, the patency of these extra anatomic reconstructions is very low, specifically at five years. And then one of the most dreadful complications in this sadly happened to one of my patients is that the grafts can actually infect and erode in patients that have poor wound healing, something that is unfortunately frequent. And so one of the greatest advances I think we've met at this particular point is that with good technique, adequate catheter sizing and the development of new covered stents that actually are good to reconstruct these aorta iliac diseases, this is that same patient. I actually did a reconstruction of his infrared aorta with stents and was able to safely take the infected open bypass out. And this patient went on to do very well. So if I may, you showed us an extreme case really. Those are really rare scenarios where you have to do extra anatomic bypass and more frequently you can do conventional surgical repair aorta by iliac and aorta by femoral bypass in LaRiche or CTO of the aorta. And it was a nice example that you showed how you can rescue this patient with endovascular approach. So not to belabor too much on this particular topic but I would like to ask you what is your current approach even though this is really advanced task classification type of a scenario, what is your current approach when you deal with LaRiche in patients with comorbid conditions, not a standard patient with low risk for surgery? Do you think more about endovascular approach or do you still use quite a bit of surgical techniques? I think Dr. Kreischer, anytime that we have these questions about this matter, we are definitely leaning in many ways on the surgeon's ability to have every tool and technique at this disposal. And so there is certainly an inherited bias whenever you face these cases. Are you comfortable with extensive endo? Are you comfortable with crossing CTOs? And is this probably the best or not for your patient? I do agree with you. Still, we push our fellows to learn exposures to understand how to expose the aorta to make retroperneal dissections of the aorta. A thing of every day for them, they have to be comfortable. But the higher risk patients, I quite frankly find myself more and more doing the endo. Now, this was an extreme case, but sometimes a very bad LaRiche with just two kissing stents into the distal segment of the aorta can be fixed rather simply. This is actually an extract from the Cobes trial, which was a randomized study to showing covered, PTFE covered stents to bare metal stents and helping us understand that we actually have pretty good patency rates that are far and beyond those of some extra anatomical bypasses that some of these patients with severe comorbidities would have had instead of an endovascular repair. So I think that we have met a lot of the technical needs and in the right training setting, a lot of these patients are served well with endovascular therapy. Excellent, thank you very much. Another very controversial and hot topic is a common femoral artery disease, extensive atherosclerotic disease, which is frequently accompanied by extensive calcification that can involve not only the common femoral artery but proximal or osteol SFA and profundum femoris. And in my experience for a very long period of time, this was a so-called no touch zone for endovascular intervention until relatively recently. Can you elaborate a little bit more? What are the latest advances and how do we treat this at the present time? And what does the future hold? Yeah, I definitely think this is a hot topic. And I think many times the discourse of no touch area or no endo area. Is or was many times pushed by just turf wars where there was attempt to protect on the surgeon side, for example, to try to remain constant and valid within. But as you have developing vascular surgeons that push and push the limits, then the no option has started to become options in many ways. But we need data, of course. This has to be, this cannot just be a discussion and certainly not a turf war. I am very happy to say that now we work much more collegially and that a lot of these things are a thing of the past, which we've obviously shown here at Texas Heart Institute where we work together. But let me bring a couple of important things here to this slide that I wanted to share. This obviously shows a rock in the common femoral, something that still I believe most of us surgeons believe the standard of care should be an endorectomy with a patch. But there was a study a few years ago, the TECO trial, which showed that there was actually low morbidity and low worm morbidity in relationships, obviously, to the wound when you would offer open versus endoin patients. And so that led my good friend, Cohen DeLuce, in the Netherlands to actually initiate a study called the VMI CFA trial. And this is just a prospective multi-center single arm effort to assess the performance of a stent with mimetic properties in the patients with common femoral disease. Now these patients should have symptomatic disease that was limited to the common femoral artery. And this is very important because I would still advocate that extensive disease into the profundo femoris is very easy to fix with surgery. And one should consider that above anything. But when I say morbidity is most of us surgeons have been in a way, shape or form, have a few skeletons in our closet about complications from groins. I will tell you, not every groin is the same. Multiple previous interventions make it very difficult to get in there. Previous surgery makes it difficult. And certainly obesity makes it a high risk for infection. And I'll tell you, dealing with a patch infection in the groin is no easy task. So in this particular study, there was technical success of 100%. And at 12 months, there was already, this is not necessarily published, but it's already been out in the public. I said it's been in some of the major vascular conferences around the world. The 12 months primary patency rate was 95.2%. And the freedom from clinically driven TLRs was 97.8. So we're showing very good results. It seems like intimal hyperplasia, which is always our fear of endovascular therapy is not as severe in the common femoral. And a lot of MRI studies functionally have shown that common femoral is actually a very stable artery. When we walk or sit, what moves is the proximal is the fey and the external iliac. The common femoral actually doesn't have a lot of forces. So as there is no extrinsic compression that severely moves this, it is probably the hypothesis behind it that the results are pretty good. So I believe that we're looking at a possible change. And I think that if the patient is risk stratified and it seems to be a bad patient for open, this seems to be a good alternative for us. Very good. I truly share reviews as far as this particular zone is concerned. And I'm very glad that Dr. Cohen de Luz who's a vascular surgeon actually moved this frontier forward because then I believe that the vascular surgery will accept it more readily than it would be by radiologist or interventional cardiologist. But I think also what is very important in my personal experience is the advent of new technologies such as shock wave for extremely calcified vessels, etherectomy devices, and stents that are durable. They don't break easily and they show pretty good long-term results as far as patency concerned. That in my opinion is one of the major factors that allowed us to be able to be where we are now with the common femoral artery disease. Here I actually have a slide to share of an example that's publicly available. But this is a situation where lithothripsy as you could see there as depicted by the image in the middle does a great job at rupturing and in a way minimizing the calcium burden as it actually can break it into smaller pieces. And you have pretty good results because we're always very worried about some very severe dissection in this territory. And of course I think there are other etherectomy tools out there that I think as we use them more, could be very good options to treating these patients and not necessarily leaving scaffolds behind. Again, no data really at this time to share on specific common femurals that's worth this causing, but certainly things that I think will open possibilities for the future. And of course we should add drug-alluding technology but it was certainly helped in this type of a scenario. And lithothripsy, we were in a trial here at our institution. We have seen some impressive results in very complex scenarios. So let's move further down to the popliteal artery and talk a little bit about popliteal or femoral popliteal aneurysmal disease. Again, for a long period of time this was completely in the domain of vascular surgery and it still might be for most of the scenarios, but I want you to share your views as far as surgery versus ten graphs for this particular problem. Right, so one thing to have in mind with popliteal aneurysmal disease is mind you, it's different from the aorta iliac aneurysms or aortic aneurysms in the sense that rupture is not necessarily the driving force. In these cases the clinical problems that patients may have is that the aneurysm itself becomes anitis for clot and there's a lot of murals thrombus and so it's not rare that these patients, if undetected, come with an acute limb ischemia as they've trashed entirely their distal flow and so recognizing this early obviously allows us to offer a good therapy. Now this slide that I present here just is a very nice diagrammatic way of showing what's currently out there for the management of these cases. So one on the left shows a medial approach with a bypass with two incisions. The one in the middle shows a posterior approach so you make an incision behind the knee and then interpose a vein and then the last one shows a stent graft which in the event that we have adequate landing zones above and below has shown good results overall. Now I think if there are lots of data and many times registries, we don't have a very solid comparable study that I could mention. There is a very nice meta analysis that has shown that mostly this has historically been repaired open that most of them have been done by medial approach but that there's certainly an important number of patients now being treated with endo. I think that it's important for us to be clear that this should be a patient-centric decision and even more so after one decides, well I think this patient is high risk or low risk, then we have to be very, very critical about the technical part because it's not as easy as saying, well I think he's high risk and I'm putting a stent in. Well in many cases you have very dilated arteries. We don't necessarily have all the gamut of sizes and certainly we have to consider that we definitely need an ideal situation when considering a stent graft to put above and below. Surgery of course is always going to have its inherited complications to the incision and or bleeding but unfortunately there's also many endo leaks that can happen both in stents or in open, specifically in the medial approach because you don't resect the aneurysm and a lot of times the sural vessels can actually continue to feed into the aneurysm and many times the size could be even compressive and giving chronic pain. I know you have a lot of experience in stent grafts and I think in very selective patients it could be an option but I think one has to caution the audience that it may not be a great solution currently for everybody. Right, yeah, we published several manuscripts from our experience with a variety of stent grafts and as everybody knows there are balloon expandable and self expandable stent grafts. Of course balloon expandable stent grafts should not be used in this particular location because of tremendous risk of crush and kink and what's also very important there is not a single stent graft at the present time approved for this particular application. There were some attempts in very early stages but they were abandoned to me for unknown reasons but I think that's the frustrating part that we do not have a stent graft that has been proven to function well over a long period of time. So I do have my concerns relating the use of stent grafts for this particular application because we do not have a dedicated stent graft. So that is obviously one thing that is within the unmet needs that we have to still have hope for that will happen in the future. I'd add to that and this is just personal knowledge is that in many times I'll reinforce the stent grafts with a mimetic stent inside but it has to be a very particular set of situations where you can actually size appropriate both the stent graft and then the mimetic stent that goes inside of that to give it a second support system. But right now I'm not necessarily sure that one can ever adventure to say that endo is gonna be primary above this. I think that open good surgical technique may probably be suitable for most patients. Very well, so this is kind of a segue to how have new technologies evolved and what can we expect as far as treatment of critical limb is concerned? I know you have tremendous experiences with treatment of critical limb ischemia. You have been involved in clinical trials and you published and presented at many different meetings on this topic. So I would like to hear your views and your experience on past, present and future and also the unmet needs in this particular disease. Correct, as you fancy under the more extreme scenarios of patients nowadays where you have severe below the knee and even below the ankle disease patterns, then you have to take into consideration many things. Now, one of the things is it's not going away and it's getting more and more. And the reason is because we have a society that is becoming older, healthcare improves and that is met with patients that are many times in phases of decay in the extreme segment of their lives but they're still patients, they deserve care. Diabetes is driving a lot of this also, a tie to increscendo obesity and then a subset of those patients was the uber complex patients are those that are in already renal failure on dialysis because a lot of the derangements of electrolytes lead to severe calcification patterns. So I think the major advancement in peripheral arterial disease intervention on the endovascular world is the understanding that it's not coronary vessels because many times we have found ourselves in history, thankfully, that we have pioneers that are cardiologists that have pushed the limits and applied tools from one territory to the other but we've obviously learned that these could be longer segment lesions, that there are different calcium patterns in those lesions. And so I would believe that technology has emerged up to the needs. I mean, we now have micro braided longer catheters of support. We have dropped the profile of crossing devices, support devices down to a very useful scenario. We have developed peripheral wires that are workhorses and then grammage of up to like 60 grams of pressure for CTO wires that you would maybe in coronaries never consider using but it is a very different scenario. And then on top of that, we have recognized much more the wound care that has to be associated to all these patients, the toe and flow. I may interrupt and ask you in particular, I remember when I started working on peripheral disease and interventions in the early 80s, critical in mischemia and below the knee disease was another what we call a no touch zone for any interventions. It doesn't matter whether you are cardiologist or radiologist or a vascular surgeon. And part of the reason for it was that we didn't have tools. I remember Dr. Schwarton was one of the first ones trying with balloon to address those particular problems and Gerald Doros, an interventional cardiologist, was brave enough to intervene and showed pretty impressive results but the tools were missing, lacking. And so if you would have 30 years ago present the information of endovascular treatment of below the knee disease, everybody would look at you and criticize you as you are heretic and you are doing something that is totally out of the range of any interventionalist. So in a way, the way I see it, I have to congratulate vascular surgeons like you to show baldness and determination to be able to move to this frontier and break those barriers to get us to the point where we are now. And as you started talking about the technology that is available now, we could only dream about it in 20, 30 years ago. So here you have an example. Yeah, this is the case. You can mention. Yeah, I wanted to show this case just because it shows a couple of things. One is that we still unfortunately today knowing how important it is to do a vascular workup, we see patients that come to our clinic that have been amputated with no vascular workup. So this lady underwent an amputation and obviously she was profoundly ischemic. And obviously the incision of the surgeon that did the foot surgery didn't work well. And also how we have a needle going from the antirelateral segment of almost at the ankle level in what seems to be a very athritic and small perineal artery, almost the size of the needle or smaller. But on top of the technology we're talking about, we've gotten much better at doing these retrograde accesses, which I really believe the bi-directional approach gets you in many times succeeded before we would have not been able. Actually, there's a paper in the journal, Vendovascular Therapy from back in 2008 while I was in Germany where we showed that up to 20% of the times we would fail to cross-antigrate. And so this has opened the panorama for many things. Now, this is an x-ray guided puncture but we always advocate for ultrasound guided as high definition. In this particular case, I won't expand with much of the angiographic results but we were able to rescue two vessel outflow which then led to the development of a transmetatarsal amputation modified. You see that there's a lot of skin missing, but here's where again that marriage of toe and flow, the podiatrist working side-by-side with a vascular interventionalist, be that an IR, an IC or a VES to understand the needs of the wound, creating a beautiful wound, seeing that patient through and then placing a skin graft for absolute wound healing on a TMA and a patient ambulatory within a month and a half of a presentation that everybody else wanted to do on above than the amputation. So I really think that we have a lot of those gaps now met. So Dr. Montero, you just mentioned a couple of very important things that have really broken the barriers and move this approach forward. One is mandatory use of ultrasound for treatment of below the knee disease, critical in viscimia, alternate access. And if anybody would like to get involved in this field, this is like an absolutely essential tool. Now, another thing what you mentioned, and I have to congratulate your colleague, Vascular Surgeons and few Interimational cardiologists that were trailblazing in this field, gaining access to distal posterior tibial, anterior tibial, or even peroneal artery with a needle with direct access was very bald and brave type of approach. In the past, we would fear this greatly because of the risk of compartment syndrome. But of course, with advancement of techniques using ultrasound, this is relatively low risk procedures. However, things can go wrong and you can certainly develop compartment syndrome. So for those, in my opinion, that are involved in this type of approach, they should be aware of it and they should know how to identify it and how to treat it or to have a proper backup. I'm talking about non-surgical interventionalists. Absolutely, a multidisciplinary team is needed and I think the interventionalist, non-surgical, should always be part of a team that has the ability of calling the rasker surgeon or orthopedic surgeon say, I think that we have a possible compartment syndrome and we need to be, you know, take care of it promptly. I would advocate, I have a few very short tips here on this to close it, but extreme access is doable and it's a good tool to save complex feet wounds. I think that patterns like orphan heel or the desert foot should be recognized and treated aggressively. Venous arterialization, which is probably a topic that you and I should talk about on a one-hour session alone should be considered, this is really breaking a lot of the boundaries of no-option patients, but advanced training is possible and courses are available all over the place and I think cadaver courses are probably the best way to go out there and train and understand what the ultrasound offers, how to put the patient on the table, what to learn and again, like you said, recognition of early complications of this patient, certainly don't experiment on patients. We just had a course like this here in Houston at the Mighty Center and this was the International Society of Endovascular Specialists, first Houston symposium where you actually own cadaver. We had 12 different stations with extra equipment and ultrasound equipment, showed to the participants all the techniques available to treat below-the-kneed complex disease and patients with critical infuscumials and thank you very much for... Yeah, it was lovely. I would just say to anybody out there, don't miss this course. This was the first of hopefully many and it's all hands-on. I was actually delightfully impressed with how great it was and I think we even made a little video so hopefully the ISEVS webpage will have it up soon but it's certainly something that I think we should continue to push on strategies. Thank you very much. This will complete part one program on breaking the barriers in peripheral vascular interventions for treatment of lower extremity arterial disease. Please join us for a part two presentations on this topic. Thank you.