BackTable / VI / Podcast / Transcript #364

Podcast Transcript: Percutaneous Transmural Arterial Bypass (PTAB) as a Treatment Option for CTOs

with Dr. Sean Lyden

In this episode, host Dr. Sabeen Dhand interviews vascular surgeon Dr. Sean Lyden about percutaneous transarterial bypass (PTAB) with DETOUR, a new therapy for treating occlusive / stenotic superficial femoral artery (SFA) disease. You can read the full transcript below and listen to this episode here on BackTable.com.

(1) The DETOUR System: A Novel Approach to Peripheral Vascular Disease Management

(2) PTAB Clinical Selection Criteria & Procedural Insights

(3) Balancing Training, Cost & Clinical Efficacy

(4) Clinical Trial Insights: Navigating PTAB Complications

(5) Transitioning from Clinical Trials to Clinical Practice

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[Dr. Sabeen Dhand]
I'm Sabeen as your host today and I'm happy to welcome Dr. Sean Lyden, Chairman of Vascular Surgery at Cleveland Clinic. Welcome, Sean.

[Dr. Sean Lyden]
Thank you very much.

[Dr. Sabeen Dhand]
You're welcome. We're really looking forward to talking about Detour today, but before we get into that, I'd love to know, how did you got to the top, tell us how did you get all the way there to Chairman of Vascular Surgery?

[Dr. Sean Lyden]
A lot of it is a little luck. I ended up at Cleveland because my wife of now 32 years-

[Dr. Sabeen Dhand]
Nice.

[Dr. Sean Lyden]
-drew a circle around Akron, Ohio and drew like a target sign, and the closer I got to that, the better I was going to do, and had two kids, wanted to have more. Then the fellow named Roy Greenberg had been my med school roommate, Roy had already gone to the Cleveland Clinic, and so I had a good friend there that was able to convince Ken Oriel to hire me. Then 23 years later, I'm one of the last people standing, and so I've worked my way to top, so nothing like a good old good hard work and a little luck.

[Dr. Sabeen Dhand]
Absolutely. You've been there for 23 years.

[Dr. Sean Lyden]
Yes.

[Dr. Sabeen Dhand]
How big is the department? How many vascular surgeons are at Cleveland Clinic?

[Dr. Sean Lyden]
Currently we have 20 surgeons and we cover all of the Cleveland area. There's five hospitals that I have partners at, and then I was just told last week that Cleveland Clinic Florida is now going to come under me, so-

[Dr. Sabeen Dhand]
Congrats.

[Dr. Sean Lyden]
-soon I'll grow six more surgeons.

[Dr. Sabeen Dhand]
Wow. That's a lot to take care of. A little bit more about your personal practice at Cleveland Clinic, do you have a particular focus or do you do just everything both open and endo?

[Dr. Sean Lyden]
I do a little bit of everything. It started out just timing-wise coming out of fellowship in 2001. I trained at the University of Rochester and learned how to do endo when not many vascular surgeons did. I was involved in many, many clinical trials, and then now having been there as the chair, also having good experience in open surgery, I do a lot of that as well. I'd say about 40% of my practice is aortic work, about 40% lower extremity, then a little bit of carotid and dialysis access as well, but do a little bit of everything.

[Dr. Sabeen Dhand]
Yes, that's a great spread. Do you have a preference? Do you like open more, endo more? Or is it you like it all?

[Dr. Sean Lyden]
No. To me that's the wild thing about vascular, is the variety. You're dealing from head to toe, top to bottom, from humongous incisions to percutaneous all the way. I think that's what really makes it most exciting to me is the variability of who I'm treating and what I'm treating.

(1) The DETOUR System: A Novel Approach to Peripheral Vascular Disease Management

[Dr. Sabeen Dhand]
Totally. I totally agree. Let's focus our work on endo and peripheral vascular disease. We know, I mean, we've been there where these lesions can be very, very tough to tackle. They're a long segment and you're battling wires from above and below. Let's talk about the Detour System. What is it?

[Dr. Sean Lyden]
The easiest way to think of the Detour System is it's a way to create a percutaneous femoral to popliteal bypass. You're going to start in the arterial side, you need basically just enough opening in the origin of the SFA to get a catheter or wire in at least 3 centimeters. Then it uses a spring loading proprietary crossing device which will puncture out of the superficial femoral artery into the femoral vein, and then travel down the femoral vein, and then use that same crossing device to cross back from the femoral vein into the popliteal artery. Then you're basically lining that segment with a PTFE stent graft, usually two or three stent grafts to cover that segment.

[Dr. Sabeen Dhand]
They use this terminology as acronym, PTAB, what does that stand for?

[Dr. Sean Lyden]
That's an acronym that Endologix came up to really to suggest that this is a therapy, so percutaneous arterial bypass. It's really instead of thinking about it's just an endovascular solution, you're really trying to create a endovascular bypass, more akin to what we would be doing if we were doing a femoral popliteal PTFE bypass.

[Dr. Sabeen Dhand]
Sure. I'll tell you what my first impression when I heard about that. What did you think when the company came to you or you heard about Detour? What did you think?

[Dr. Sean Lyden]
Fortunately, I've known about it from the very beginning. It came as an idea by Jim Joy. I'm one of the board members for VIVA. Jim was a fellow board member and Jim sat at one board meeting talking about this crazy idea he'd come up with and that he was using off-the-shelf devices and patients that he treated endovascular with multiple failures to now go outside of the artery into the vein and then reline the entire system. When he first told me about it, I thought he was absolutely crazy.

I'm like, "Why would you ever do that?" Then watching him then create a startup and say, "Hey, it seems like we can actually create a unique device and a unique covered stent." Then he came to me, said, "Hey, would you be interested in helping leading this clinical trial?" The one thing I know from my 22 years of being a vascular surgeon is that if you think that endovascular will not eventually find a solution to replicate and improve on what we could do surgically, you're completely wrong, and so when the opportunity came up, I was happy to jump on it.

[Dr. Sabeen Dhand]
You did already talk a little bit about devices, but let's go a little bit more in detail. What's access like? Is it a six French access up and over when you're doing these cases because you want to target the proximal SFA?

[Dr. Sean Lyden]
Currently the crossing system requires an eight French system, so you're going to have an eight French crossover sheath come from the contralateral common femoral, and then you're going to need venous access on the ipsilateral side most commonly coming in the posterior tibial vein with the six French sheath and just using a commercial snare.

[Dr. Sabeen Dhand]
Is it easy to direct the spring-loaded system towards the snare? Is it all just fluoroscopic? Do you need to use any ultrasound guidance or?

[Dr. Sean Lyden]
When the trial began, we did do CT scans, and I think for the people that had not done venous harvesting of the femoral vein or had any idea of where the femoral vein sat in relation to the superficial femoral artery it was very helpful, but for the most part, once you get venous access in the cap and advance a wire all the way up to the femoral vein near the common femoral vein junction, you're just going to put a commercial either single-loop or tri-loop snare, and so you have a target because you can fluoroscopically visualize it. Then the crossing device has markers on it to figure out which direction it's pointing, and then you can then get the two structures superimposed on top of each other and then fire the crossing device.

[Dr. Sabeen Dhand]
Got it. Then what size are these stents that you're putting from the proximal SFA down into the popliteal artery?

[Dr. Sean Lyden]
When the trial began and now that it's got FDA approved, the stents are really limited to three different diameters, and so they are up to 7 millimeters in diameter. You can treat an artery that goes between 4.5 and 6.7, so they have three different diameters currently with their current offering.

[Dr. Sabeen Dhand]
Are you sizing these arteries with IVUS at all as far as what the proximal SFA is looking at or what the distal popliteal is looking like?

[Dr. Sean Lyden]
It can be done with either CT, IVUS, or angiography. I am fortunate that in where I work, we were given a gift from the Koch company, from Bill Koch and we have a CT scan right in the office, so when the trial began using CTs for lengths and sizing, anybody that it's not going to be a contraindication to give them that the small amount of dye to get a CT scan, I still prefer to get a CT scan. I think you get great both length and diameter measurements. Then I tend to use IVUS very liberally. I found IVUS is much more accurate than angiography, so if I'm not using CT, I'm using IVUS.

[Dr. Sabeen Dhand]
Perfect. What is the furthest distal on the pop you can go back for the second anastomosis, essentially?

[Dr. Sean Lyden]
Correct. for the trial, you had to have at least one vessel patent runoff, and you had to land at least 3 centimeters above the tibial plateau.

[Dr. Sabeen Dhand]
Okay, so above knee. Any below the knee pop usage you've done?

[Dr. Sean Lyden]
You had to land there, so it ends up being sort of right behind the knee. The way I look at it, most of them ended right somewhere in the midpoint of the patella.

[Dr. Sabeen Dhand]
Have you done any cases that are technically below pop just because the lesion was too long in the fem-pop?

[Dr. Sean Lyden]
No. The trial itself didn't allow that. Like I said, you had to land with 3 centimeters above the tibial plateau, and it just got FDA approval in May of 2023, and I'm excited that we have our first case actually this Friday at Cleveland Clinic.

[Dr. Sabeen Dhand]
Oh, that's awesome. The big elephant in the room, and I think my first impression when I heard about the device is like, "How are you not causing obstruction of flow in the femoral vein and how are you not increasing the risk of DVT?" Tell us more about that.

[Dr. Sean Lyden]
That was one of my concerns as well. Fortunately, being part of the trial and discussions with the FDA, there was a lot of safety things built into the trial to evaluate that. The first thing was you either had to have a duplicated femoral vein or you had to have a femoral vein that had at least a 10-millimeter diameter, and so if the largest device is seven, you're still going to have some flow around the femoral vein. In my surgical practice, I use the femoral vein a lot for infected devices, infected aortas, and infected other things, so I know you can take the femoral vein without really any significant consequence to patients, but the big concern was both DVTs and PEs. We just reported the two-year data at the Society for Vascular Surgery Vascular Annual Meeting in May of 2023, and the rate has been really low at 4% for DVT, and there's not been any pulmonary embolisms in the trial. It's really borne out that this does not cause a lot of long-term issues.

[Dr. Sabeen Dhand]
Totally. It's pretty amazing when you think about it. There's a 7-millimeter potentially stent that's sitting in the vein and not causing DVT. Are you putting these patients-- are they anticoagulated as far as medical therapies?

[Dr. Sean Lyden]
The trial required aspirin and Plavix throughout the duration of the trial, but when the trial began, we would have never guessed, but the VOYAGER and the COMPASS trial came out during the trial, which showed that if you're on a direct oral anticoagulant, you have lowered acute limb ischemia events, and so a lot of the investigators wanted to try those in our patients. We really then said you could modify from aspirin and Plavix using rivaroxaban or some of the other direct oral anticoagulants as standard care, and so that was allowed within the trial, and so if patients wanted to be on it or they had some other reason to be on anticoagulation, it was okay.

[Dr. Sabeen Dhand]
What about if they had a history of DVT or anything, was that a contraindication?

[Dr. Sean Lyden]
Exactly. When the trial began, if they had-- they had to have ultrasound to evaluate their ipsilateral vein, but if they had a history of a DVT or did not have an adequate sized ipsilateral femoral vein or a duplicate vein, they could not be enrolled on the trial.

(2) PTAB Clinical Selection Criteria & Procedural Insights

[Dr. Sabeen Dhand]
We've already talked about some of the selection criteria, but what would be the ideal patient, and then what are some key contraindications that you guys looked for?

[Dr. Sean Lyden]
For the trial allowed severe claudicants, people with rest pain, even with ischemic ulcers, so Rutherford 3, 4, and 5, the amazing thing was we really wanted to be using this in complex lesions, so the lesion had to be at least 20 centimeters in length. It could be a CTO, it could be diffuse stenosis, it could be in-stent restenosis, because of the size of the stent graft, the reference vessel that you're treating had to be bigger than 4½ millimeters and it had to be less than or equal to 6.7 millimeters.

We talked about you had to be able to get in or access the origin of SFA and you had to have a adequate landing zone at least 3 centimeters above the tibial plateau with one tibial vessel runoff, and then the femoral vein had to be at least 10 millimeters or duplicate. In terms of contraindications, if the patient could not tolerate [unintelligible 00:13:33] therapy, if they had an infectious issue, a connective tissue issue, if they'd had a prior DVT or pulmonary embolism, so very standard exclusion criteria for other trials.

[Dr. Sabeen Dhand]
Of the patients you included in the trial and also moving forward, how many patients had already endovascular treatment done on the primary lesion? Almost like a failed endovascular intervention.

[Dr. Sean Lyden]
If we look at the patients that had prior treatment, just about a third had had prior stents. To me, the most impressive thing of the trials, if you look at the treatment length of the lesions, the lesion length normal to normal was 32 centimeters, and so where most SFA fem-pop trials are 4, 6, 8-

[Dr. Sabeen Dhand]
This is huge.

[Dr. Sean Lyden]
-10 centimeters long, this one was 32, and to me, that's really the one thing that really stood out the most where the average CTO length was 220, and so these were patients that had pretty significant lesions and very aggressive. I've treated these patients endo, I've retreated them endo, but I think if you have that CTO that's densely calcified or in-stent reocclusion that you might spend hours and hours on, I think this is going to really add to what we can offer them.

[Dr. Sabeen Dhand]
Yes, I'm just imagining some of those patients that we've had where you just see all that calcium, right, on that fem-pop and you're just like, "Oh, how am I going to do this?" A lot of times those patients don't have great tibial runoffs though, but in that patient that just has a total fem-pop disease, like a brick of calcium, this just seems like an amazing option. Where is Detour going to fit in your algorithm now? Do you think it's going to take a bulk of your femoral popliteal disease? Is that going to be your first option, or is it going to be reserved for a specific subset?

[Dr. Sean Lyden]
I think it's still going to be reserved for a subset. If you look at both the BASIL trial and if you look at the BEST trial, we know that vein bypass works. My practice has always been in someone that I'm going to take to the lab for an intervention. I've always got vein mapping. Then I always try to understand what their heart's like. Do they have coronary disease? Is it symptomatic? What's their EF like? I always tell patients endo works, but it sometimes doesn't last. It may last, it may not last, and depending on how complex it is, it will be how it lasts. I generally do endovascular first, but I also sit there and say, depending on how sick the patient is or how good their vein is, how long I'm going to try doing it.

If it's a short calcified lesion, 100% of the time endo. Moderately long lesion, moderately calcified, 90% of the time endo. If it was a 40-centimeter long occlusion and they had good vein, I probably would do a vein bypass, but before I ever again do a prosthetic bypass, I would do this all day, every day. Those times when I spent three or four hours trying from above or below, poking through stents to try and redo an endovascular intervention, I got to admit, going to do this instead. I think after I get to play with the device the way I want, now that the trial's done, I'll get a better understanding of how I can push this technology and how it might grow in what I do.

[Dr. Sabeen Dhand]
How steep was the learning curve when you first started from the beginning?

[Dr. Sean Lyden]
It's really not. One of the things we did, because you need to have both arterial access and venous access and we're a big department, we said that we would have more than one physician doing the case, even though we're a training institution and you have trainees, sometimes having a staff physician who knows what they're doing is much, much easier. Our very first case took an hour and 20 minutes. I think the two things that provide a little issue for some people is if you don't do a lot of venous interventions or you're not used to using ultrasound guided access yourself, the hardest part, I think the learning curve of the trial for many of the investigators was getting a percutaneous posterior tibial vein stick, and so that took longer than most of the case for everybody.

[Dr. Sabeen Dhand]
What about how fast does the case now on average take you? The first one, an hour and a half, what are the–

[Dr. Sean Lyden]
They basically took about that period of time. The trial required a complete leg runoff before the procedure, after the procedure. It also required treatment of inflow of iliacs, which was okay. If you look at total procedural time, I don't think it reflects what it's going to take now it's FDA approved and commercial because I typically would get a CT scan ahead of time, and if their inflow is good, I'm not going to treat it at the time, I'm not going to get all those extra pictures because we don't get paid for it, and if you already have some other way of imaging it, it's completely unnecessary.

I can imagine that once it's commercial approved that it's probably going to take people somewhere between an hour or two. Probably most of the patients were done with local anesthesia, but some were done with general anesthesia. At our institution, the very first one we did it under general anesthesia, not because the patient needed it, but I always find when you're doing a new device and it's a new trial, you want to be perfect and you want to be able to talk openly amongst the team-

[Dr. Sabeen Dhand]
Exactly right.

[Dr. Sean Lyden]
-about your plan so it goes best for the patient. Whereas sometimes it's a little harder with an awake patient who's asking what's going on while you're doing it. They don't understand.

[Dr. Sabeen Dhand]
They're like, "Why are you asking how to do this?" [laughs]

[Dr. Sean Lyden]
Exactly. With the crossing device, all crossing devices where it's the commercial Outback or the Pioneer or this crossing device, the EndoCross, they'll have their hieroglyphic you have to look at to know which direction the crossing device is aiming at, and so in the room, we'd have these big posters of what it looks like everybody agreeing that, "Okay, we all agree this is the direction we're pointing," because I sort of look, it's like carpentry, can measure a bunch of times, but you only get cut once, and so if you're firing the crossing device, you ideally want to make sure everybody's on the same page. "We're heading where we think we are and get it across the first fire every time."

[Dr. Sabeen Dhand]
Speaking of the crossing device, it must have a longer needle than Outback or Pioneer, right?

[Dr. Sean Lyden]
It does, and it's also spring-loaded.

[Dr. Sabeen Dhand]
Spring-loaded, it's a very like quick jab.

[Dr. Sean Lyden]
Yes. You basically, you cock load the spring and it throws out, don't quote me on this, but I think it's 15 millimeters. I always tell people, when you play with the device, be very, very careful because when they're showing it to you and we showed it to sites and we had training, if someone were to push the fire, it'll go right through your entire finger. Yes. It will cross a stent. It'll cross calcium. I have to tell you, I'm excited for it to be approved because I can see all the other anatomies that I'm now going to want to use this device because for Iliacs-

[Dr. Sabeen Dhand]
It sounds awesome. That's exactly what I was saying. I was like, okay.

[Dr. Sean Lyden]
-venus interventions. I've already thought about all the different anatomies that because this thing, the Outback, you're pushing really hard with your finger, and if you can't push hard enough, it doesn't cross, same way with the Pioneer, where this thing just, it's like a gun, it comes out so fast.

[Dr. Sabeen Dhand]
That's amazing. You said that the device now it's FDA approved as of last month or a month and a half ago. Is it now available? Any site can get it?

[Dr. Sean Lyden]
It should be soon. From what I am told by Endologix, I think we will be the first US case. The trial we did in the United States was called the Detour 2 trial. It was preceded by in Europe, the Detour 1 trial. In Poland and Latvia, they had the most experience and they've been using this device as part of their practice for three and five years now at some of the sites.

[Dr. Sabeen Dhand]
That's amazing.

[Dr. Sean Lyden]
US, it's ready now, but I don't think anybody's gotten to use it yet.

(3) Balancing Training, Cost & Clinical Efficacy

[Dr. Sabeen Dhand]
Do you think is there a plan as far as say, "Once I can get it at my hospital"? Is there like a training or proctor type of system for this, or just go ahead and do it?

[Dr. Sean Lyden]
No, a lot of the discussion, because this is a novel device and it's really tried to become a therapy, was that the agreement with Endologix and the FDA part of the approval process is there will be a mandatory required training. I've already done mine and I've helped lead one. They know they've done three so far nationwide, and so that's going to slow the rollout, but I look when there's a new unique therapy, the best thing a company can do is make sure that you have everybody as trained up as they can be so their results are good.

I'm sure it'll frustrate a few people waiting to get their hands on it, but I look at it that when EVAR came out, if we hadn't spent a lot of time training people, we'd had a lot more complications, and so when things are new, sometimes spending a little extra time to show people how a device works, talk through good case planning, talk about lessons learned in the trial, about cases that are good for the trial and cases that are bad and those kinds of things are kind of unique.

[Dr. Sabeen Dhand]
I know. My mind is already running about different cases that I can just use this on. I had a case last week of just totally occluded stents in the fem-pop, I mean, 10 years. This would be perfect just bypass that easily with a nice landing zone in the pop. What about another elephant in the room is cost? Is this going to be like a $20,000 device or is this going to be something that is very easy for smaller hospitals to use?

[Dr. Sean Lyden]
That I don't know yet. As of at least the last time I talked to Endologix, about 10 days ago, they had not said all on the cost. I said that I had already talked to our endovascular new product committee at the Cleveland Clinic because we were part of the trial. I had exemption on worry about cost on the first case so we can evaluate it, but then it'll go to our value analysis committee to decide how and where it can be used. To me, the argument of what's going to help get it through most value analysis committees is it will provide a solution that current technology doesn't. It'll allow treatment of patients that don't, and if you look at the durability of endovascular devices for these kind of lesions, it's terrible. At least the two-year data that we now have available, the patency is better than what it would be of a surgical PTFE bypass.

[Dr. Sabeen Dhand]
What is the two-year patency for this now?

[Dr. Sean Lyden]
I just presented it at the Vascular Annual Meeting. I think you have to realize there's a couple of things to talk about. If you talk about the different definitions of patency, the trial defined patency as that there was not a clinically-driven target lesion revascularization, and by duplex, there was not a peak systolic velocity ratio greater than, equal to 2.5. The reason why I point that out is from PTFE bypasses, duplex is completely not helpful in predicting stenosis or occlusions. If we took the patency as defined, it was 59.4% at two years, but if we just look at the freedom from clinically-driven TLR, it was 76%. Then if you look at it just the way we do a PTFE FEM bypass, is it open or not?

With a PTFE fem-pop bypass, I could get a duplex today and it looks perfect. I get a duplex and it has a stenosis and it goes on to be fine or thrombosis the next day. For most of the studies we looked at, the patency at two years is probably somewhere between 60 and 70%, and this trial, if you look at 24 months, open or close, it was 87.6%. The key is then you don't have all those wound issues. As a vascular surgeon, PTFE FEM bypass, we'll brag it's two hours, it's an easy case until you develop a wound infection that goes down to the graft, which is then catastrophic to the patient in terms of limb loss. That's, to me, the other exciting thing is I can do something I could do surgically without all the wound issues.

[Dr. Sabeen Dhand]
Yes, it sounds like if you're going to do a proximal SFA to PTFE bypass, you're not going to do that open anymore. You're going to do it via the Detour. There's no point.

[Dr. Sean Lyden]
Exactly. If they needed something done to their femoral profunda, I would still do that, but otherwise, if I don't need that or if I can do that beforehand and stage it, I'm doing this every day.

(4) Clinical Trial Insights: Navigating PTAB Complications

[Dr. Sabeen Dhand]
That's awesome. I honestly I'm very excited to see this. One thing is kind of hard to talk about, too, but did you see any kind of weird complications during your experience with Detour that were unexpected, the stents causing a dissection or anything like that?

[Dr. Sean Lyden]
No. The one big complication we had during the trial was when we stopped requiring CT scan ahead of time and we allowed people treatment of common femoral disease concomitant with the procedure with a good outcome, the one acute occlusion we had was a person who had a common femoral atherectomy and into the profunda origin, and when we looked at the CEC, looked at the films after the case, they really didn't get the lumen of the common femoral profunda open enough, and that acutely occluded.

The other key thing is, I think, something that anybody who does any ultrasound imaging or does any interventional radiology will realize is that you get a film around the stent grip. No different than if you have a tunneled center lining or dialysis lining, they get fibrin sheath lining that device. I think one of the reasons we don't see the late DVT and PE risk is this device basically it's a fibrin layer around it. The normal way you define DVT on an ultrasound is lack of compressibility, lack of flow.

The Core Lab had to come up with new definitions because you now have a vein that you can see a flow channel, you can see it compress, but it won't compress all the way because it's now arterialized, and so if it's a duplicate vein, it's easy, but if you don't, it's not. I think the one thing that we're going to have to get out there is that when someone has this and the patient is going to have to know or maybe have some sort of card to help the ERs when they come in with leg swelling for some other cause that it doesn't get reported out as a DVT because the ultrasonographers are not going to know what they're looking at when they see.

[Dr. Sabeen Dhand]
They're going to be like, "What is that flow channel?" I actually would love to see what that ultrasound looks like, that there's this like graft within a vein and it's flowing the different flows. It probably looks pretty gnarly.

[Dr. Sean Lyden]
It works really well, but I tell you we had to basically modify the definition of DVT. We saw this fibrin sheath usually like a millimeter thickness, but it's no different than any other prosthetic device you live with in the venous segment. I think the key to remind people is that, hey, we put a new arterial channel in the vein. It's okay. You cannot squish because that's pressurized artery. You're going to compress the remaining venous channel, and at least through two years, we've only had that 4% instance of DVT and we should have the three-year data soon by this fall. We'll hopefully present it at a meeting next spring.

[Dr. Sabeen Dhand]
Back to the creating that channel. Any issues with deep venous reflux and someone who might have like superficial venous reflux, too? Did they have worse leg swelling or some symptoms like that?

[Dr. Sean Lyden]
In the trial, we did look at the venous clinical severity score and the Villalta score through one year and there was no increase in venous morbidity. It was not collected out after two years, mostly knowing that when you harvest the femoral vein, if they don't have a morbidity by year, we've not seen that in the surgical literature, and so it's no different than if you harvest the femoral vein from something else and you tie it off, they do get a little bit of leg swelling from the calf down. I tend to put my surgical patients on compression stockings. I've done the same with my PTAB patients, just said it's going to swell a little bit, but six months later, it'll be completely back to baseline, and that's what I found.

[Dr. Sabeen Dhand]
Yes, I'm sure. Their extreme claudication went away that, they don't mind the little swelling.

[Dr. Sean Lyden]
No, they don't care at all. It's no different than if you revascularize those people endovascular surgically, their legs swell. I always remind myself when patients come back to the ED because they have a swelling issue, it's usually because I forgot to tell them that once I restore flow, they're going to swell, and when you remind people that that's going to happen and say, you need to put ACE on or elevate your legs, they're always, "Oh, yes, that means the flow is better. I'm so happy, Doc." As opposed to when you forget, they call the ED and they're like, "No, that's normal. You don't have a DVT. I know you're going to get a DVT ultrasound, but it's fine."

(5) Transitioning from Clinical Trials to Clinical Practice

[Dr. Sabeen Dhand]
[laughs] Yes. The other question I had, these things are coming in my head while we're talking to you. You said it has to have a single patent tibial runoff. Can that be a recanalized tibial during the procedure or it needs to be a–

[Dr. Sean Lyden]
For the trial, it couldn't be. Now, once it's FDA approved, I'm sure people will want to do what they can, but we know from endovascular treatment that the more tibials you have open and the bigger the tibials are, the better that anything we do in the fem-pop segment is going to be, so I'm sure this device will be no different. Once it's FDA approved, you have someone with severe disease and you treat their tibial and have a good result, I am sure there will be people that get treated with PTAB. Hopefully they do a bunch of it right about it, but at least during the trial was excluded.

[Dr. Sabeen Dhand]
It's going to be quite remarkable to see what kind of quote off-label techniques people are going to use with this in different areas. I think it's going to be pretty remarkable.

[Dr. Sean Lyden]
To me, the unique thing is I've always felt that when I have some of the flush SFA occlusion, it doesn't reopen into a tibial. If you're going from a 5, 6, 7 millimeter proximal vessel into a 3-distal and you have to treat it, the results are never as good. I think that's something that we saw if we looked at the BEST trial, whereas the BASIL trial was really more just tibial disease. If you could actually have a good treatment of the below-knee POP and tibial and get a good outcome, I think it would completely change the durability of having a PTAB in there to treat the occluded femoral popliteal segment. To me, that person with reoccluded stent graft that's super, super calcified lesion that you spend forever trying to use etherate to be on or lithoplasty on or-

[Dr. Sabeen Dhand]
Long case.

[Dr. Sean Lyden]
-stents designed for that, they're long, long cases, and if I can just avoid all that.

[Dr. Sabeen Dhand]
A hour-and-a-half sounds amazing.

[Dr. Sean Lyden]
Right. Exactly. Anybody who has a bunch of this in their practice, you tell them, "You can do this an hour-and-a-half," they're like-

[Dr. Sabeen Dhand]
Yes, sure.

[Dr. Sean Lyden]
"Okay." Then they'll do it, and they'll say, "No, it really wasn't that hard."

[Dr. Sabeen Dhand]
Yes. Sean, this has been great. Any kind of parting words of wisdom to people who are either familiar or unfamiliar with Detour and thinking about bringing this into their practice?

[Dr. Sean Lyden]
Hopefully we'll have the report out there of the outcomes for one year of the JVS as where we're going to plan on submitting it to you, hopefully in the next week or so. The trial results for the two-year presented at the Vascular Annual Meeting, so they will be available through that format. I just tell people when you're getting new devices and having trained people on carotid stents, SFA stents, atherectomy devices, EVAR devices, TEVAR devices, look at what the trial looked at, try to make those your first patients. Don't try to do the hardest case your first case, and once you're good at it, then kind of live off, kilter a little bit, trying to do something harder.

You can play around a little bit, but I always tell people that I always do the straightforward, simple cases because I want when I now have the device in my hands to prove I can continue to do what I did in the trial and that my results are good, and not to sit there and find the worst, hardest case that everybody would say, "You did it and it's great." You want to sit there and reproduce those outcomes from the trial of your own first before you start doing the really toughies.

[Dr. Sabeen Dhand]
Yes. No, that's great advice. Don't start off with something so hard and with the new device, that's just going to make things 10 times tougher. Sean, thank you so much. Thanks for taking the time to be on our podcast today and teach everyone about Detour and PTAB. I think it's something-- it's almost-- this thing is too good to be true. All the stuff you're saying, it's so nice. I'm really looking forward to now seeing it in clinical practice in other people's hands, and hopefully we can bring it into my practice too. This sounds great. literally my mind is already spinning with multiple patients who'd benefit from this. Thank you so much. Thanks, Nick, for being our engineer today. We look forward to seeing you again, Sean. Thank you.

[Dr. Sean Lyden]
Thank you so much for having me. It's been my pleasure.

Podcast Contributors

Dr. Sean Lyden

Dr. Sean Lyden is the chairman of vascular surgery and a professor of surgery with Cleveland Clinic in Cleveland, Ohio.

Dr. Sabeen Dhand

Dr. Sabeen Dhand is a practicing interventional radiologist with PIH Health in Los Angeles.

Cite This Podcast

BackTable, LLC (Producer). (2023, September 11). Ep. 364 – Percutaneous Transmural Arterial Bypass (PTAB) as a Treatment Option for CTOs [Audio podcast]. Retrieved from https://www.backtable.com

Disclaimer: The Materials available on BackTable.com are for informational and educational purposes only and are not a substitute for the professional judgment of a healthcare professional in diagnosing and treating patients. The opinions expressed by participants of the BackTable Podcast belong solely to the participants, and do not necessarily reflect the views of BackTable.