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Viabahn BX Balloon Expandable Stent-Graft (Gore) For SFA Lesions: Indications And 2-Year Results: Advantages And Limitations
Viabahn BX Balloon Expandable Stent-Graft (Gore) For SFA Lesions: Indications And 2-Year Results: Advantages And Limitations
angiogramangioplastyballooncontralateralevarexpandablefreedomGORE MedicalGore Viabahn VBXiliaciliacsimprovedinfrarenallengthlesionslumensmatrixocclusionocclusiveostialpatencyrenalsrutherfordstentstent graft systemstentssustainedtasctechniquetherapeuticVeithviabahn
Advantages Of The Gore VBX Balloon Expandable Stent-Graft For F/EVAR, Ch/EVAR And Aorto-Iliac Occlusive Disease
Advantages Of The Gore VBX Balloon Expandable Stent-Graft For F/EVAR, Ch/EVAR And Aorto-Iliac Occlusive Disease
anatomiesaneurysmaneurysmsaortobifemoralaortoiliacarterybrachialbranchcatheterizedCHcustomizablecustomizedistallyendovascularevarexcellentFfenestratedFenestrated GraftfenestrationflarefollowupGORE MedicalGore Viabahn VBXgraftgraftshypogastriciliaciliacsmodelingoccludedocclusiveparallelpatencyperfusionproximalpseudoaneurysmPseudoaneurysm of the proximal juxtarenal graft anastomosisptferenalsSelective Catheterization of the Right CIA to Hypogastric Arterystenosisstentstent graft systemstentstherapeuticVBX Stent Graftvesselvesselsvisceral
Clinical Experience With The New BeGrafts: Potential Advantages?
Clinical Experience With The New BeGrafts: Potential Advantages?
aneurysmsarteriesBeGraftBentley InnomedceliaccoveredcurvaturedeployF/BEVARfavorfenestratedfenestrationsgraftgraftshypogastricoccludedpatencyradialstentstent graft systemstentstargetTEVARtherapeuticthoracoabdominaltransitionType II TAAAuncoveredvisceralvisibilityvisiblezone
Panel Discussion (Session 59a) 2018
Panel Discussion (Session 59a) 2018
BeGraftBentley InnomedGore Viabahn VBX (Gore Medical)stent graft systemtherapeutic
The Phoenix Hybrid Atherectomy System: The Basics
The Phoenix Hybrid Atherectomy System: The Basics
atherectomybaselinecalcificdebriseaseembolienrollingimprovementinterimobservationalocclusivePhoenixPhoenix Atherectomy Systemrutherfordstenosisstudytherapeuticwire
Endovascular Treatment Of Chronically Occluded Saphenous Vein Grafts: A New Treatment Horizon That Can Be Effective: Techniques And Results
Endovascular Treatment Of Chronically Occluded Saphenous Vein Grafts: A New Treatment Horizon That Can Be Effective: Techniques And Results
acuteanastomosesangulationanteriorarteriovenousbypasscatheterschronicChronic Occlusion of BypassdilatationdilateddistalextravasationfemoralfemoropoplitealfinalFistulaGORE MedicalGore Viabahn VBXguidewiresnativeoccludedocclusionpatencypatientpedalpoplitealproximalPTArecanalizationrecanalizeresidualrupturesaphenoussegmentstentstent graft systemStent Placementsurgicaltherapeuticthrombectomythrombolysisthrombustibialveinviabil
Value Of Drug Eluting Stents (DESs) To Salvage Failed Or Failing Vein Grafts
Value Of Drug Eluting Stents (DESs) To Salvage Failed Or Failing Vein Grafts
anastomosisaneurysmsangioplastyarteryassistedballoonbilaterallybypassbypassescabgcDEScomparablecomparedconduitcoronarydistaldistallydrugdrug elutingDrug eluting Coronary StentelutingendovascularfailuregraftgraftsinfrainguinalInterventionslesionsmechanicalneointimaloccludedOpen RevisionoperativeorthopedicpatencypatientsperformedperinealpoplitealprimaryproximalrecurrentsaphenousstandardstenosisStenosis of Distal AnastomosisstentstentstechnicaltherapeuticthrombosedtibialveinVeith
Comparable Long-Term (4-Year) Outcomes Of Grafts Of Greater Saphenous Vein And PTFE With Bonded Heparin (Propaten) For Tibial Artery Bypasses: Does A Distal Vein Patch Make A Difference
Comparable Long-Term (4-Year) Outcomes Of Grafts Of Greater Saphenous Vein And PTFE With Bonded Heparin (Propaten) For Tibial Artery Bypasses: Does A Distal Vein Patch Make A Difference
anastomoticarterybypasscohortcomorbiditycomparablecomparedconnectconnectingcreatecreateddistalDistal anastomotic patch creation)distallyfemoralFemoro-posterior tibial artery bypass (Heparin-bonded Propaten graftGORE MedicalGore PropatengraftincisionlengthlimbLong segment SFA stent occlusionmultipleoperativepatchpatencypatientpatientsposteriorproximalptfesalvagesaphenoussurgeonstechniquetermstherapeutictibialtypicallyundergoingunderwentvascular graftveinvessels
Are Fempop Bypasses With Heparin Bonded PTFE (Propaten) Durable Treatment For Long SFA-Pop Occlusions: When Are They The Best Treatment And Why
Are Fempop Bypasses With Heparin Bonded PTFE (Propaten) Durable Treatment For Long SFA-Pop Occlusions: When Are They The Best Treatment And Why
autologousbypassclaudicantscomparisoncriticaleradicationGORE MedicalGore Propatengraftischemiajournallimblowocclusionpatencypatientperformedprimaryprostheticptfepublishedrandomizedrateregistryreinterventionresultsaphenousscoresubgroupsurgicalsurvivaltherapeuticvascularvascular graftvein
Transcript

- It's an honor to be here at Veith and talk about the Viabahn BX two year results in iliac lesions as well as some insights into that. We know that ballon expandable covered stents are superior to regular non-covered stents for TASC C and D lesions and there are a lot of advantages of what we can treat in the iliacs with these types of devices.

That said, the original devices had some limitations, they had a fairly small size matrix both in terms of length and diameter, they were fairly rigid and they foreshortened if you tried to make them significantly larger. The Viabahn BX and other newer ones,

have potentia the size matrix is much larger, they are conformable, you can inflate them larger with a lot less foreshortening, therefore making them more tailorable throughout the length of the stent

and they have improved deliverability. These are just pictures of the balloon expandable Viabahn BX stent. This size matrix brings a smile to all of our faces. If you look at the number of lengths available, up to 79 mm in length and the fact that you can make them

up to 16 mm in diameter with less foreshortening. Well, their IDE approval trial has been published, we were in that trial and it showed beautiful results. I point this slide out in red just to show the complexity of the lesions, a lot of TASC C and D, contralateral access,

kissing stents and external iliacs, so more complex than the usual iliac trials. Despite this complexity, the technical success was 100% as defined here and you can see here at nine month low MAE rates 2.3% TLR, no other major events.

If you looked at the nine and 12 months data you can see that there was improvement of at least one for Rutherford Becker, 95% and the ABI was improved and these improvements were sustained at 12 months. If you looked at primary patency and freedom from TLR, in the IDE trial, again outstanding at one year, 97%

and maintained at 12 months. What about two years? Well here the results now available at two years, you can see the freedom from TLR at two years was outstanding, well over 90% in each of the subgroups with exception of external iliac arteries

and the freedom from clinically driven TLR was almost 98% at two years. Here shows that the TASC C and D lesions treated with the VBX, did extremely well, 95% freedom from TLR at two years. There were maintained clinical

and objective evidence at two years as well. The vast majority of patients, 94%, were still improved with a Rutherford Becker, only 1% worsened. The ABI remained well above 0.9 at two years, significantly improved from baseline. And the indices of walking distances in questionnaires,

again significant sustained improvement at two years with this study. I'll end with two cases highlighting the beauty of this stent. This is from our own lab, ostial occlusion ectatic disease on the right,

occlusion on the left, crossed and treated with angioplasty and you can see that there's a little gradient here so we we had to treat this with a short stent, we wanted to cover this longer ectatic disease. So, this gives us a long stent on the right, a short one on the left and the ability to tailor it

and those kind of results. And finally, the CERAB technique, you're going to hear a presentation on this eloquent technique next but we love this now with this device. This is an occlusion of the infrarenal abdominal aorta,

shown here, very small aorta. You can see this is only 8 cm between the renals and the bifurcation. We were able to cross that. This is a VBX implanted precisely and again you'll see this technique demonstrated next talk.

We post-dilate that part with a non-compliant balloon and then placed two of the VBX stents above the internal iliac, matching them in the aorta. And there's the final result and again, a very complex aortic occlusive case and more importantly five month CT angiogram looks beautiful.

And if you look here, on the actual images here's a CERAB technique right here. You see both lumens widely patent, both iliacs widely patent. Well, I can conclude, even if PowerPoint won't let me conclude.

The conclusion of this, is a unique balloon expandable covered stent. It has a lot of potential advantages and the nine month and two year data look outstanding and I think it's an important addition to our armamentarium. Thank you very much for your attention.

- I'm going to take it slightly beyond the standard role for the VBX and use it as we use it now for our fenestrated and branch and chimney grafts. These are my disclosures. You've seen these slides already, but the flexibility of VBX really does give us a significant ability to conform it

to the anatomies that we're dealing with. It's a very trackable stent. It doesn't, you don't have to worry about it coming off the balloon. Flexible as individual stents and in case in a PTFE so you can see it really articulates

between each of these rings of PTFE, or rings of stent and not connected together. I found I can use the smaller grafts, the six millimeter, for parallel grafts then flare them distally into my landing zone to customize it but keep the gutter relatively small

and decrease the instance of gutter leaks. So let's start with a presentation. I know we just had lunch so try and shake it up a little bit here. 72-year-old male that came in, history of a previous end-to-side aortobifemoral bypass graft

and then came in, had bilateral occluded external iliac arteries. I assume that's for the end-to-side anastomosis. I had a history of COPD, coronary artery disease, and peripheral arterial disease, and presented with a pseudoaneurysm

in the proximal juxtarenal graft anastomosis. Here you can see coming down the thing of most concern is both iliacs are occluded, slight kink in the aortofemoral bypass graft, but you see a common iliac coming down to the hypogastric, and that's really the only blood flow to the pelvis.

The aneurysm itself actually extended close to the renal, so we felt we needed to do a fenestrated graft. We came in with a fenestrated graft. Here's the renal vessels here, SMA. And then we actually came in from above in the brachial access and catheterized

the common iliac artery going down through the stenosis into the hypogastric artery. With that we then put a VBX stent graft in there which nicely deployed that, and you can see how we can customize the stent starting with a smaller stent here

and then flaring it more proximal as we move up through the vessel. With that we then came in and did our fenestrated graft. You can see fenestrations. We do use VBX for a good number of our fenestrated grafts and here you can see the tailoring.

You can see where a smaller artery, able to flare it at the level of the fenestration flare more for a good seal. Within the fenestration itself excellent flow to the left. We repeated the procedure on the right. Again, more customizable at the fenestration and going out to the smaller vessel.

And then we came down and actually extended down in a parallel graft down into that VBX to give us that parallel graft perfusion of the pelvis, and thereby we sealed the pseudoaneurysm and maintain tail perfusion of the pelvis and then through the aortofemoral limbs

to both of the common femoral arteries, and that resolved the pseudoaneurysm and maintained perfusion for us. We did a retrospective review of our data from August of 2014 through March of 2018. We had 183 patients who underwent endovascular repair

for a complex aneurysm, 106 which had branch grafts to the renals and the visceral vessels for 238 grafts. When we look at the breakdown here, of those 106, 38 patients' stents involved the use of VBX. This was only limited by the late release of the VBX graft.

And so we had 68 patients who were treated with non-VBX grafts. Their other demographics were very similar. We then look at the use, we were able to use some of the smaller VBXs, as I mentioned, because we can tailor it more distally

so you don't have to put a seven or eight millimeter parallel graft in, and with that we found that we had excellent results with that. Lower use of actual number of grafts, so we had, for VBX side we only had one graft

per vessel treated. If you look at the other grafts, they're anywhere between 1.2 and two grafts per vessel treated. We had similar mortality and followup was good with excellent graft patency for the VBX grafts.

As mentioned, technical success of 99%, mimicking the data that Dr. Metzger put forward to us. So in conclusion, I think VBX is a safe and a very versatile graft we can use for treating these complex aneurysms for perfusion of iliac vessels as well as visceral vessels

as we illustrated. And we use it for aortoiliac occlusive disease, branch and fenestrated grafts and parallel grafts. It's patency is equal to if not better than the similar grafts and has a greater flexibility for modeling and conforming to the existing anatomy.

Thank you very much for your attention.

- Well, thank you very much, Enrico, and I am going to discuss a graft that is not available in the United States, and I'm going to discuss 'em outside IFU, or an off-label use, so I am in for some trouble in this session. These are my disclosures, and I was part of the early launch group of the BeGraft+.

But I go back to the reason why we stent those fenestrations and, actually it was done by John Anderson, and in the early days it was to guarantee the option to re-catheterize the target vessel. Later, we moved to balloon-expandable covered stents, because we moved up the aorta,

but also because we saw that the patency of the covered stents was better than the uncovered stents. And finally, we know that these balloon-expandable grafts are very easy to deploy precisely and are very conformable, as you can see in this image. Another important point is the purpose of relining

with a self-expandable uncovered stent. That is usually to prevent kinking in a ballon-expandable covered stent, and to smoothen the transition zone with the target vessel. With that in mind, we can look at this new family of the BeGraft.

The middle of those grafts is the new BeGraft peripheral that is actually indicated for fenestrations in our center, and the BeGraft+, which has an extra layer with a sandwich technique, is even stronger, which we use for branches. And you can see that this graft has a higher radial force,

whether it's necessary, we don't know, but what in my mind is more important, is that it's very kink-resistant when you use it in branches. Here you see video by the company to demonstrate the superiority over other balloon-expandable covered stents

and this is the off-label use for us, BeGraft+ in branches, as I said, high radial force, kink-resistant and flexible, and a very nice visibility and the BeGraft in fenestrations. We started using the BeGraft+ in branches because of the tactile aspect of the graft. I had it in my hands and I found it, indeed,

very kink-resistant and I thought that would be very interesting. So let me show you two examples. In somewhat more difficult anatomy, certainly, in the beginning here you see a celiac trunk and you can appreciate the visibility of the stent graft.

You can also appreciate that it adapts nicely to the curvature of the vessel, and this is a post-op CT in different directions. This is another case where we used it both for visceral arteries and an IBD, and you can see the path of the renal arteries here

and the hypogastric artery. And here again, the images that go with the procedure and the deployment and the post-op CT scan. So, again, we use this in fairly difficult anatomy to start with. 57 BeGrafts in total,

both in thoracoabdominal aortic aneurysms and in IBDs and we had one occlusion, and that occlusion, to go back to the beginning of my presentation, was clearly due to a very angled transition zone in the target vessel.

The patient occluded came in acutely, fortunately, and we were able to recover that kidney and obviously extend it with a self-expandable stent. Now, let's move to the BeGraft, and here, it's more because of the available length that we were very interested by that graft,

because we have other grafts that do a very good job. This is a complex case where you can see fenestrations being treated by the BeGraft. Again, a very nicely visible graft, easy to deploy very precisely and also easy to flare. I must be honest with you,

we used the Lifestream before that when we needed the 27-28mm length, and we found out that the Lifestream was far more difficult to flare and tended to jump forward. That's the reason we stopped using that in favor of the BeGraft.

And here you can see the same in the SMA and obviously in this patient with a branch for the celiac, we used a BeGraft+. Experience mainly, not only, but mainly in that typical length of 27-28mm, 52 BeGrafts in total

and we had not one single problem up to now. So to conclude, for me, I'm very happy to say that the BeGraft and BeGraft+ are clearly a new generation bridging stent grafts, covered stents, that are kind of more fenestrated and branched design. They are very visible and very kink-resistant,

and as mentioned before in the previous presentation, all lengths are available. And don't be fooled, if you have a problem with a transition zone, you may still need to reline with a self-expandable stent. Thank you very much for your attention.

- [Interviewer] I mean it's got to be challenging to discuss a graft that none of us have seen but we can start with Jim. Jim can take on anything. What do you think of this new B graft? - [Jim] Well, yeah, I have fortunately been able to see it over in Europe and being teased by it. I guess the concern I have is the thickness of the fabric.

It seems like it is two layer of PTFE and stent sandwiched in between, so you're getting thicker and thicker so if you're using a smaller B Graft Plus, are you concerned about low flow and thrombosis with it? - You may say so.

First of all, it's only the B Graft Plus that has that dull technology and the reason is clearly that it's designed for branches and usually you use, now a days, branches in the larger vessels, mostly the celiac and SMA. We have gone done is using branches for renal arteries

for that precise angle having to reline, because let's be honest, if you use an autograft, you will very much more likely reline it with a self expandable stent to prevent the kinking, so the end result is the same.

So the answer to your question, Jim, is no, I'm not concerned more than with any other bridging stent graft. - And what about the distal flexibility of the B Graft. I mean, that's kind of what's driven me to go to VBX is that, you know, I had a couple patients that came in that

they kind of kinked and you had one in your series there. The VBX tends to be much more flexible distally. - Yeah, I am probably the only guy in this world that is not completely convinced yet by the VBX and I've listened to you, I've listened to Gustave, and to Mark Farmer,

and I hear a few little things here and there. The flexibility is excellent, the tactile feeling of that graft is excellent. I agree that the B Graft Plus feels much harder, but it is very kink resistant and that's why I pointed out

that's the transition though is still important because that indeed is, can in an angle be a problem. So you have to choose it correctly. - So, Jim, in the VBX, and you've done a lot of cases, how often did you have to put an additional stent to fix a kink?

- The only time I've ever had to put another is for length. I've never had to reinforce or put a self expanding end. For like the one that I showed where I went from did it as a parallel graft going all the way down, I had to use two there because they only come in 79 and the one problem we have is when you start,

like any balloon expandable stent, when you start oversizing it and they actually have eight that will go to 16 as Chris pointed out, but it will start for shortening, but I have not had problems where I had to support it with a self expanding stent.

- But also when you enlarge it, you lose some of the radio force, no? Probably the reason you didn't have a kink is because the area that you, actually, the area that could be kinked is not dilated enough. You want to dilate approximately or distant it to fit more

of the the anatomy then you lose of the radio force, I guess. Theoretically at least. - Only the 8L is really expandable beyond two millimeters. So a six you can dilate up to an eight. So I really haven't seen that tremendous for shortening

except with the L, and obviously I'm not going to put an 8L into a renal or a vishal vessel. - The length of the Bridging Stent Graft is interesting though. We are doing far more fenestrations, and if we do Branch Grafts is usually grafts with both

fenestrations and branches, and you have to deploy these grafts based on the position of the fenestrations, and then you plan your branches to be fairly near through the target vessels. Say you end up using more like six centimeters instead of eight centimeters.

We virtually don't use the 79 or the eight millimeters Covera anymore. Having said that, there are new designs, designs from other companies coming out where you are planning even longer Bridging Stent Grafts up to ten 15 centimeters but we will have to see wither that

induces new risks. - I think that was one thing that we found interesting 'cause we also use them for parallel grafts and then you do need longer ones because in the cuffs we never put more than two parallel grafts at any one place, and so if I'm doing it, I'll do like a celiac SMA

and I'll put cuff in there and I'll come down and I'll do the renal so as parallel for torrical abdominal, since we don't have readily available access to the stuff that you have. But then I need longer, so if anything I'd like to see longer than 79,

just for some of these other grafts and the advantage is you go in, you put a six in, and you can flare it to eight to go in the celiac and SMA but you gutters only at a six. - Chris I have a, just one second - Chris the SFA, the VBX for the SFA, when is an over kill and when do you think

it's absolutely decaded? - For the SFA? - SFA. - Yeah, I got to say, I have not used a balloon expandable stent in the SFA very often. I guess if you really had an hospitable reason

that you really needed a stent in precision and short maybe you'd use it. You know, I think the title given here was a misnomer because it was a two year results instead of SFA trial. Truth be told I've used a whole lot of them in the aorta and the iliac and some of the extensions that Jim and

Eric have talked about but I've never used one in the SFA. I think it would be, you know I think if we have other options for the SFA, the viabahn, nitinol stent and then you could reinforce that if you needed to with an interwoven stent if you really needed a pave in graft.

I've not used it in the SFA. - Any question from the audience? We have a couple of extra minutes. - Is the cuffs playing a role for the VBX because in Europe it's clearly more expensive other bridging stent grafts and I heard from the Munster Group,

off the record, when they do chimneys with the VBX the reline it to increase the retinal force. So what about the radio force? - We followed ours going up to two years or as long as VBX has been available for that, we haven't an increase instance of crush or need

for relining. The cost is, and all cost is local, but a 018 viabahn is more expensive in our office than the VBX of equivalent size and length. - And that's the same in our lab as well. - Yes sir.

Introduce yourself and ask the question please. - [Eka] I'm Eka Jaan, so sorry, I'm from Hartford. Question for Doctor Mackenzie regarding the VBX and the fenestrations. Do you have any concerns with the unsupported portion of the VBX at the transition zone with the fenestrations,

it's not supported there so can it collapse or can there be offset between the fenestrations? - That certainly was a concern. I always deploy my stents as 90 degrees the axis so if I've got a four dot fenestration and I turn it to a three dot so I know I'm right perpendicular and I literally will

try and land between the two wire forms so it expands and actually kind of as the grommet seals there, and all the ones we have done we have no had any endoleaks at the approximate aspect of the stent and quiet candidly I'd rather have a leak there than include a stent at distal aspect 'cause I can always come in and put a

balloon expandable which, of course I haven't had to do. - Yes, last question. - [Andy] Hi, Andy Plum, Chicago. Along those lines, yesterday the Munster Group was doing a workshop and they actually favored the Atrium stent over the VBX.

For that reason, they are saying they've seen with the VBX, because the stents are independent without a cross bridge that they've actually seen shortening like accordioning with time with their ChEVARs. Now this was a medtronic presentation, little bit biased towards medtronic,

but they were actually favoring the Atrium stent for their ChEVARs. - My problem is the rigidity of the Atrium stent and it's crushability. Here you've got a little bit more play, David Muino would come out and tell is to do

the eye of the tiger with that and you can do that it but I have not seen for sure accordioning of it especially in a graft that you're using as a parallel graft. Now I guess at the very top you could, it may come down a little bit above the area of where you're

interfacing with the graft but it's going to give it more stability so I'm just not seeing that being a problem, either with implantation or long term follow up. - Thank you.

- My disclosures, which aren't relevant, but, so the Phoenix Atherectomy System. So it's an atherectomy catheter. It has no really capital equipment. It's easy to use, you can hold it in your hand. The wire has a wire clip and a bag to collect the debris.

Take a second. So Archimedes probably, arguably, antiquity's greatest genius. So if you remember, Archimedes felt this Archimedes screw and literally used it to pull water out of a river,

such that it could be used. Much like the Phoenix Atherectomy System, it isn't dealing with water, it's dealing with plaque, but it's a cut, capture, and clear system. It has a frontal cutter.

It captures the debris and uses this Archimedes screw to remove the debris back into the bag. Again, capturing clearance, there was less than 1% rate of symptomatic distal emboli in the EASE trial, which we'll

get to in a second. It's very easily used. It's small. You can hold it one hand and holds to a wire clip. And it's very easily delivered. It's low profile.

In terms of personalization of care, we've talked a lot about this, it can be used for below the knee, it can be used above the knee lesions, as well as from soft to calcific plaque. As you can see here to the right,

these are two intravascular ultrasound images. To the left, heterogeneous plaque with a pretty much occlusive lesion. And then after the using 2.4 millimeter device, an increase in a lumen size of about 67%. Talking about the EASE study,

this was performed by, the primary author was Dr. Tom Davis out of Detroit. And what he did was, he looked at 128 patients and used an array of lesions, the majority of which were below the knee. 58% technical success with using this

atherectomy device was 95.1% . 30-day major adverse events was low at 5.7%. The improvement of greater than one or equal to one Rutherford class in 74.5% through 30 days and for 80% through six months. Six-month freedom for TLR and TVR was 88%

and 86.1% respectively. In terms of the second study, the Phoenix Registry, this was a prospective, multi-center observational study enrolling 500 patients. Currently, it's at 250, of which 142 were CLI patients. The CLI patients were followed out to 12 months.

Looking at the demographics, a significant proportion were diabetic. Smokers as you can see here in red. The mean length, approximately eight sonometers in the Rutherford 2-3 and 11 sonometers in the Rutherford 4-6.

Baseline stenosis in the CLI was about 90%. Looking at the CLI group, the majority had below the knee, as expected at 74% and looking at the whole group in terms of chronic total occlusions, was about 42%. Looking at the results of the study thus far,

if you looked at the Rutherford class change from baseline of all comers, it improved by greater than one at about 56%. If you looked at all improvement, or no change in Rutherford class, it increased to 98%.

If you look specifically at CLI subgroup, it improved by one in approximately 71%. If you look at no change or any improvement in Rutherford class, it included the whole population of the CLI subgroup. So in summary, and for future outlook,

the Phoenix Atherectomy System performance at this interim analysis of registry data is consistent with the findings of the EASE study published by Dr. Davis. Interim results reveal similar safety and efficacy profile including the CLI population.

Interim data show durable improvement in CLI patients. And then the Phoenix Atherectomy System is a viable solution in the treatment paradigm for all spectrums of peripheral arterial disease. Rutherford classes two through six.

Thank you very much for your attention.

- I would like to show, very shortly, my limited experience because we have done a very strong selection with patient having a chronically occluded femoropopliteal or femoral distal bypass with a saphenous vein. We know as a general concept that the saphenous vein bypass is the best option for recanalization,

very long occlusion in SFA or popliteal artery in patient having critical limb ischemia. In case of an acute or recent occlusion of saphenous bypass, the options are well-recognized local thrombolysis or PTA plus stenting, surgical thrombectomy or surgical revision

and the patency primary secondary patient is very good. But the question is when we have a chronic occluded bypass, and one solution has been published using the native vessel to recanalize

and to try to have patency of the native vessel, but the result are not so good. Other solution might be a new saphenous bypass, medical therapy, and an attempt, we have done, to recanalize the occluded bypass.

We start the considerations about our experience. Negotiation of anastomoses may be especially the distal troublesome. Advance of our guidewires and catheters to the occluded segment is usually easy. The acute or late, in terms of hours,

late rupture may occur. And saw with the availability and the use of stent-grafts is mandatory. And a close follow-up, in terms of hours and days, and so on, is suggested. This is kinds of chronic occlusion of bypass.

You can see during the recanalization, extravasation a cure that we put a Viabil at this side. And after several dilatation also in the distal part of the segment, we have a good result, but in the proximal part,

even on the right side, we can see some irregularities of the wall. And so, the following day, we saw good patency of the stent, but a rupture, a new rupture in the proximal segment of the bypass.

A new bypass Viabil was positioned. Very good, the result, at the final angiography. This another case in which recanalization was obtained using only a bare stent in a segment of residual stenosis. Note the patency of the anterior tibial artery,

probably due to embolization, occlusion of the pedal artery. 24 hours later, pain and leg swelling occurred, and you can see the result, very clear, extravasation there. We put a Viabil stent

with a very good result. And please note, the recanalization is spontaneous circulation of the pedal artery. This another case with occlusion, chronic occlusion of the distal part of a bypass, maintained patency,

patent in the proximal part because of arteriovenous fistula remain venous. And the advance of the wire was easy. And with the help of a catheter, we overcome the angulation in the distal segment, we dilated very easily.

At this side, we can see that there is a residual stenosis, and we dilated with 18 atmospheres, and we had a rupture of the vein. And again, we put a Viabil stent with a very good result, at the final control. But the patient discontinued

double antiaggregation. And one month later, a new occlusion developed, and we performed a thrombolysis with rTPA, a total dose of 20 milligrams. And that this is the final result. Some residual thrombus in this segment

in the femoral segment of the bypass, but the final result is very good. So, these are our results. Seven patient has been treated during the last four years. Three died in the first year of follow-up. The remaining four are free of symptoms

with double antiaggregation. Only in one, the bypass re-thrombosed and restoration local thrombolysis and angioplasty. So, my final comments are the following. This method is feasible. Vein wall is very fragile and may rupture.

It is necessary careful monitoring for this kind of procedures. Stent graft of different size and length should be available. And it is questionable to do a preventative protection of this entire segment of the bypass

with stent grafts. Thank you for your attention.

- Good afternoon, I'd like to thank the moderators and Dr. Veith for inviting me to discuss our experience with using coronary drug eluting stents to salvage failed or failing vein grafts. Vein graft stenosis is the major cause of delayed graft failure after infrainguinal bypass.

It affects one-third of bypasses and reduces primary patency. Obviously the gold standard is open revision, but there isn't always conduit for that. It requires a general anesthesia. The result of endovascular interventions

have been largely disappointing. In particular, conventional peripheral stents are way too large to treat most saphenous vein bypass grafts. Coronary drug eluting stents are a better match from a size standpoint

to saphenous vein bypass grafts and they have a mechanical advantage, or many mechanical advantages over balloons, especially with regard to watermelon seeding. The scaffold of the stent prevents the balloon from slipping proximately

or distally when your dilating the stent. Finally, the mechanism of vein graft stenosis, especially at anastomoses, is neointimal hyperplasia, so the drug eluding stent is rational and obviously it's been proven in saphenous vein grafts used for

coronary artery bypass grafting when compared to angioplasty and bare metal stenting. So this is a case of proximal stenosis of a bypass graft arising from the femoral artery, which we treated with a balloon mounted coronary drug eluting stent

with an excellent technical result. We retrospectively looked at our experience doing this from 2012 to 2017 and we looked at the following outcomes. Primary stenosis-free patency, assisted graft patency, graft occlusion,

amputation, and then I'll talk about this briefly, comparison to standard endovascular interventions on the same patients in the same bypasses. We put 21 drug eluting coronary stents and 19 lesions in 17 patients bypasses. All of these bypasses were either

baloney popliteal bypasses or tibial bypasses using saphenous vein bypass graft. The lesions were most likely or most often just distal to the proximal anastomosis or at the proximal anastomosis, although three of them were at the distal anastomosis.

Twelve of them were performed after failure of angioplasty at the same operative setting. The others were performed as a primary intervention in a single setting. Operative technical success was 100%, primary stenosis-free patency

and assisted graft patency were good at six months and declined from there, as you might expect. Five patients occluded their grafts during follow up and that resulted in four amputations, but twelve bypasses, or 70%, were still open at the end of the follow up.

We compared the 21 coronary drug eluting stent interventions to 23 more standard endovascular interventions for lesions of saphenous vein bypass grafts. When we compared the two approaches for all lesions, we didn't see any difference in primary stenosis-free patency

between the coronary drug eluting stents and the more standard endovascular interventions. Similarly, for recurrent lesions we didn't see any difference. But for primary treatment of initial lesions in saphenous vein bypass grafts,

there was better primary stenosis-free patency for the coronary drug eluting stents then for the standard endovascular interventions. So a couple of caveats. This is a single institution experience, it's a small sample size.

However for these tough lesions threatening bypass grafts, we saw that the majority of coronary drug eluting stents placed after immediate PTA failure were technically successful. Half of them were placed for recurrent lesions

and we did see a kind of patency that was at least comparable to standard vascular interventions. Here's a woman who was in a lot of trouble when she originally came to us. She had had bilateral knee arthroplasties

with a tourniquet, but she had popliteal aneurysms bilaterally that the orthopedic surgeon didn't recognize. So she thrombosed both her popliteal aneurysms. She only had enough conduit for a bypass on one side

so she got an above knee amputation on the other side. But the one side had kind of a not so great of saphenous vein and not so great of perineal artery, but we performed the bypass

and I then had to intervene on this bypass graft a number of times to keep it patent. And here you can see a stenosis at our distal anastomosis and some disease in her perineal artery that we treated with a drug eluting coronary stent

with an excellent technical result and this leg is still attached and she's walking. So again, in a small cohort at a single institution, I think this experience demonstrates that coronary drug eluting stents

provide durability at least comparable to standard endovascular interventions for the treatment of infrainguinal bypass graph stenosis that threaten bypasses and coronary drug eluting stents definitely performed better than

standard endovascular interventions in initial lesions. I think these results warrant further clinical investigation. Thanks.

- Thank you. I don't have any disclosure. Okay here we go. Okay, good I want to start off my talk by presenting with a patient that I typically see in my practice. He's a patient presenting with a left foot gangrene,

his past medical history's significant for diabetes. Of note, he had a prior open heart surgery of which saphenous vein has been harvested. He has treated with hyperbaric treatment without any improvement and also has had multiple endovascular interventions.

The angiogram of this patient typically show something like this. He has to have multiple stent placement in his femoral artery as shown in the picture to your right. And a single vessel run off in the middle

with a very prominent on the foot. Given the fact that he has no available saphenous vein with the multiple failed long segment occlusion in femoral artery this patient is someone we would offer osulc or femoral bypass to tibial artery using a heparin-bonded Propaten graft.

Specifically we will also add a so called distal anastomotic patch to create in the distal site. So for those in the audience who are not surgeons you may wonder what does that mean? Well over the several last two decades surgeons

have made efforts to improve the bypass graft patency particularly for distal bypass by creating some kind of anastomotic compliant devices. So some examples such as Miller Cup, Taylor Patch in the middle showing with a patch in the distal anastomotic site.

There our colleague from Great Britain also popularized the St. Mary Boot. Linton Patch is the one that's used in our study which is basically we create a patch in the distal artery followed by a PTFE graft. Another device has been popularized recently is creating

a vein patch connecting the artery and then together create a fistula. For this patient we created proximal artery anastomosis very typically making an incision in a proximally, created an anastomotic incision, connecting the PTFE or the Propaten graft to the artery.

Distally we made a distal incision by isolating the posterior tibial artery we create a patch first using either saphenous vein or bovine patch. Follow that we create a connecting PTFE graft to the patch and this patient had a very different recovery.

Post-operatively day 10 you can see an improvement by day 30 the wound is fully healed. With this as a background, we created the so-called posterior tibial bypass using a heparin-bonded PTFE Propaten graft with a distal anastomotic patch.

So we recently published and analyzed our outcome and I want to share with you the results of our publication. This was published last year which expands over 15 year period. We compared two groups in which a patient underwent saphenous vein bypass graft was compared

to those patients undergoing this technique which is called the Propaten graft with distal vein patch. In the Propaten group there were 62 patients. They underwent a proximal PTFE connection to the femoral, distally connected to tibial vessels with a patch followed by PTFE graft connection to a.

Cohort 46 patients who had skip incisions in which we harvest the saphenous vein connecting from a femoral to tibial vessels with multiple long incisions. Both group had a very similar epidemiological and comorbidity group and in terms

of underlying baseline comorbidity bypass indications, Rutherford classification both group had a very similar results. In terms of the operative time of note that patients undergoing a PTFE graft has less operative time compared to the vein graft.

Of note, the Propaten graft typically takes us less than three hours whereas a vein graft typically takes approximately five hours. Length of hospitalization in part because incision has also resulted in a difference in the hospital stay.

Now proximal anastomotic sites also varies. For the PTFE graft the majority of our patients that we can connect it with ease to the common femoral artery. In a vein graft, in part because the length of amobility, sometimes we have to connect to the femoral

or popliteal artery. So in term of primary patency, both group at four years followup have very similar primary patency approaching 65%. In terms of secondary patency, both groups also have very similar results

approaching 75 to 80%. In terms of limb salvage, both groups has also very comparable limb salvage rate at 48 months with a rate approaching 90%. So we will also perform a analysis variate including univariate and multivariate analysis

we found that in our cohort active smokers also the poor runoff scores were inversely related to the outcome. So in summary, our study showed that by comparing the femoro-tibial bypass graft using the Propaten it was a distal anastomotic patch.

This technique has a very similar comparison in terms of patency and limb salvage rate compared to the traditional vein graft connecting to tibial vessels and Propaten graft specifically has a shorter operative time and also shorter length of stay.

In treatment success is inversely related to tobacco use and poor outcome. So in conclusion we found that this particular technique has a very comparable tibial compared to a very typical outcome compared to a vein graft and it's a very viable conduit

in patient who does not have available vein graft undergoing tibial vessels bypass. Thank you very much.

- Current guidelines support the role of open surgical bypass in long occlusion of superficial femoral artery, provided that a good quality autologous saphenous vein is present. However, a good quality saphenous vein may be lacking in up to 40% of the patient with critical limb ischemia.

And also, the results of alternative autologous materials are not so satisfactory in comparison with prosthetic grafts. For the reason, when a good quality vein is not available, prosthetic graft remains an acceptable alternative. Among the various materials studied during the years

for below-the-knee bypasses, heparin-bonded PTFE graft reached promising results in recent years, and provided significantly better result than those obtained with standard PTFE in recent North European randomized trial. Since 2005, our hospital is the coordinating center

of a multicentric registry involving seven Italian teaching and regional hospitals, concerning the collection of all the intervention performed with heparin-bonding graft in recent years. Our registry obtained twice validation from an external company who certified

the reliability of our data. And today, I'm going to present our updated result of 2017 with more than 1,300 heparin-bonded PTFE bypasses performed mainly in patient with critical limb ischemia in the below-knee setting. Up today, the median duration of our follow-up

is about 38 months, and involves nearly all the patient in our registry. As far as the results, in the above-knee bypass are concerned, you can see that we recently published in Journal of Vascular Surgery this paper

showing excellent result at eight-year follow-up, with primary patency approaching 60%, both in claudicants and in patient with critical limb ischemia. And if we look at the result in patient with intermittent claudication,

we recently sent and were accepted for publication in the JVS paper on such a bypass in patient with claudication, showing again ten-year results of primary patency of about 60%, with a low rate of reintervention during follow-up.

When we look at the results in the below-knee setting in patient with critical limb ischemia, the results are equally satisfactory, with a five-year primary patency of 40% and secondary patency of about 50%, with good results in term of amputation-free survival.

In the attempt to identify which patient can mostly benefit from the use of this graft, we published last year in the World Journal of Surgery a predictive score for amputation-free survival in our patient. We created a score including the five characteristics,

age, coronary artery disease, end-stage renal disease, tissue loss, and poor runoff. And we are able to identify three subgroup of risk, patient with a score from zero to two, low-risk group, patient with a score from three to four, medium-risk group,

and patient with score from five to 11, high-risk group. And you can see that five-year amputation-free survival declined from the low value to the higher one. And we were able to see that in patient with low-risk group, five-year amputation-free survival is about 70%, which is not far different

from the result obtained with autologous vein in most published series. Intermediate risk subgroup has a amputation-free survival of about 50% while high-risk patient had a very poor result, 25% amputation-free survival at five years.

As far as the rate of infection is concerned, again we submit recently a paper to European Journal of Vascular Surgery. We had a low rate of infection, about 2.3%. However, these cases had poor outcome with a high rate of amputation and mortality

despite complete surgical eradication of the infection. In conclusion, to answer to the question of my presentation, it's probably a subgroup of patient with a low score does exist in which you can suggest the use of heparin-bonded graft if primary method, also in the presence

of an available vein. Under this point of view, prospective randomized comparison with autologous vein in patient with low-risk is underway in our centers. Thank you for your attention.

- [Audience Member 1] So I have a question for Dr. Jackson, but maybe everybody else on the panel can chip in, and it just has to do with what your first intervention is going to be for a focal stenosis in a vein graft, and I guess, Ben, my question is, in general, is your first time you intervene going to be a drug-eluding stent?

Our strategy generally has been, to start with, a cutting balloon based on a series, I think it was from Schneider, who compared it and saw pretty good results. Nowadays, I think maybe I'd do that, and at the same time then put a drug-coated balloon in, and that's

increasing the cost, there's no good data to say that's better than just a cutting balloon, but I think I might do that and reserve the drug-eluding stent for the second time or third time. So my question is, what's your intervention the first time you intervene endovascularly

for a focal vein graft stenosis? - [Dr. Benjamin Jackson] So if you're not going to do an open revision, right, we'll preface with that, I'll use a coronary drug-eluding stent first. - [Audience Member 1] Okay. - [Speaker 1] Okay, so, are you happy with that?

- [Audience Member 1] Well, I was hoping to get other opinions, but if you want to move on, that's fine. - [Speaker 1] Alright, so I'll give you my opinion. I don't think there's anything wrong with putting a stent. The idea that the stent is going to be occupying space and is going to mess up your next procedure, I think

that's more out of fear than actually the reality. We have patients that in the SFA popliteal segmentary, we're on the fifth round of stents, and you'd be surprised how you can distend the fifth stent inside the SFA. I never thought it was possible, actually.

We have some IBIS documentation showing at least a five millimeter lumen after you do that thing. So I'm not so concerned about that. The problem with this, and I agree with putting a stent because there's a very rigid lesion sometimes. It's not easy to balloon them, it's not easy to

because usually the cutting balloon probably already got the lumen that you want, but then definitely it increases the cost that way. Again, who knows the other answer. Anybody else? - [Dr. Chris Metzger] Yeah, a brief comment.

I don't think all vein graft lesions are alike, so it depends if it's diffused or focal. The other thing is, I think your response to initial therapy is important, so if you do your balloon, cutting balloon, then it's going to tell you recoil, not recoil,

and the other thing I would say is intravascular ultrasound, if you're in doubt on how large that is, I think helps a lot. So, you know, if it's very focal, very high grade, I think drug-eluding stent is perfect, the question is what size, IBIS helps with that.

Otherwise, I think your strategy for longer disease might be a reasonable strategy as well. - [Dr. George Adams] And the only other comment I'd make is if there is a thrombotic component like Chris was saying, depending on the client morphology I might use laser atherectomy followed by a

biologic therapy such as a drug-coated balloon. - [Speaker 1] Yes, sir? - [Audience Member 2] About that last presentation, are you using any type of anticoagulation when you do these PTFE tibial bypasses, or were the groups comparable where there's only antiplatelet

therapy in the vein grafts and in the prosthetic grafts, or are you putting all of them on factor 10A inhibitor coumadin? - [Dr. Peter Lin] So our patient, we typically put them on aspirin, and for the Propaten we don't add any distal antiplatelet agents.

- [Audience Member 2] Because that's a lot better than historical reports, probably. I wondered, why do you think it shows so much better, even with previous vein cusp patches? - [Dr. Peter Lin] So I think the patch matters, and I also think that over the years, we also learned

a whole lot about the distal anastomotic patch, because time won't let me tell you something and go into great detail. So the patch, you know, we make, is about two to two and a half centimeter long, so that length of the patch is almost twice the length of

the diameter of the graft itself, so I think that's also a significant factor. So it's something that previous literature has not really emphasized on, and the PTFE ideally should be connected to the proximal one-third, instead of distal one-third, so that also may make

some of the same area boost configuration. So the whole idea is you want to make the patch as long distally as possible. So some of the variations, I think, have in part helped, and ideally is that the vein is available, that would be great, if not we also have used a lot

of bovine patch as our patch material, so that thing I think made a lot of difference. So I don't think, all things considered, antiplatelet agents played a huge role, but I think the distal anastomotic compliance mismatch, if we can alleviate that, it will help your outcome.

- [Speaker 1] So Peter, you believe that those grafts have a thrombotic threshold, or you think there's no thrombotic threshold for PTFE? - [Dr. Peter Lin] Oh, I think so. - [Speaker 1] Let me just continue my thought process. So if there is a thrombotic threshold, it doesn't matter

how long you're going to put the vein patch. You can put a 16 millimeter vein patch, it's not going to make any difference, if you reach that thrombotic threshold. So then we come to the criticism that maybe you're selecting the cases

with good runoff, and in the good runoff, it's hard to show a difference between vein and (unintelligible) bonded with the patch, maybe. But if you are to do those terrible cases that have an isolated TPO segment, or they're all the way on the foot or the plantar arteries, that maybe the

saphenous vein will come up much better than this. What do you think? - [Dr. Peter Lin] Well, these are all great points. It's hard to discern based on a single yes or no answer. Saphenous vein has certain limitations, although I believe there's still a standard of care

in terms of conduit choice. Often times the veins are sclerotic, we're limited by vein length, so again, I brought up some points that in some patients we can only connect it to a superficial femoral, even a popliteal bypass because the vein is not long enough.

So PTFE, while it's not perfect in some scenarios, it does have advantages, because I can connect it even to the external iliac artery, I can connect at the common femoral artery, so that's that benefit. I did mention very briefly in our multi-vein analysis, the single vessel runoff is the (unintelligible) runoff.

So in those cases, you're going to have bad outcome no matter what kind of conduit you use, I do believe that, but in general we'd just use aspirin for that patient. But I believe that if we do believe there's an underlying prothrombotic condition, we would add additional anticoagulants, but that's not typical routine practice.

- [Speaker 1] Alright, I just want to add that in poor runoff situations, the vein clearly does better, and it works for a long time. We had published three years ago, on plantar arteries in branches of tibial vessels in the foot, and they did work, only with vein.

Everything else kind of failed, even with the fistulas. Yes, sir? - [Audience Member 3] I have just a quick question about the Phoenix device, a two part question. A, do you use it with a filter, or can you use it with a filter, and two, do you use it as a standalone therapy

or adjunct to a drug-eluding balloon or anything else? - [Dr. George Adams] So, in general, atherectomy is always with adjunct balloon angioplasty. In regards to the filter, especially with the Phoenix device, you have to be careful and very selective with the wire that you use,

you want to use a nitinol wire. So for a filter usually I use a free-floating filter, the NAV-6, and you can't use it over that nitinol wire, you have to use a graduated tip wire, usually a Viper or a Viper Flex. So I would select cases where you would not use

a filter specifically with this device, so if you have a long lesion or if there's any thrombotic component to it, I'd be very conscientious of using this device with that. - [Speaker 1] Thank you. Any questions from the panel?

Because I have a few questions. - [Dr. George Adams] Actually, it was I think very stimulating as to the conversation we just had, in regards to thrombotic or anticoagulants with antiplatelets, you know. Recently the COMPASS trial just came out, as well

as an E-PAD which was more or less a pilot study, showing that just taking peripheral arterial disease regardless of grafts, there seems to be a thrombotic component, and factor 10A inhibitors may have benefit in addition to antiplatelet therapy in regards to all PAD patients.

I think it's a very interesting discussion. - [Speaker 1] I have a question, Dr. Dorigo. Once you identify the high risk group of patients, is there any strategy to modify them to improve them and get them to another category? - [Dr. Walter Dorigo] Most of the perimeters we

examined were not modifiable. Age, extension of disease, coronary artery disease. Maybe one possibility is to improve the runoff status but, in concomitance with the intervention, one can try to improve the runoff score. But four out of five factors were not modifiable.

- [Speaker 1] Thank you, okay. I have one more question. So, do you do distal bypasses? - [Speaker 2] We do distal bypasses, I personally don't. I have a big group, I have three people in my group that only do distal bypasses.

- [Speaker 1] So, it says a patient in your group does not have a saphenous vein, and has a limited runoff. How will you approach there? - [Speaker 2] Well, that was a question I would want to ask both Walter and Peter.

Is there a role for composite bypasses? Because we do it quite a lot where we only have shorter parts of vein available, shorter lengths of vein available, we would do the above-knee PTFE, and then cross the knee with the vein. But I remember that last year at this meeting,

the Americans said that it's worse results, but we still do it. - [Dr. Walter Dorigo] Yes, in the registry are a crude amount, so about one, 150 composite bypasses with the short or long segmental vein and the part of PTFE graft, we use it.

And the results are not particularly better than those with the grafts, but it's likely better. - [Speaker 1] Right, I want to ask the panel, if you have the use the common femoral artery as an in-flow, and this vessel has been used

a few times before, what do you prefer to use? The external iliac, redo the groin again, or use the deep femoral as an in-flow? We'll start with Peter Lin. - [Dr. Peter Lin] I would probably go to external iliac,

because higher, it's got proximal better vessels, and it's greater diameter, all things considered. If you go deep femoral, you still got to navigate across a stenotic plaque common femoral artery. - [Speaker 1] No, it's not stenotic, it's a normal vessel. - [Dr. Peter Lin] So, I would, if all had been equal,

obviously common femoral might be better, but if common femoral's highly disease, stented and treated, and so there's a lot of scar tissue, I'd probably go with external iliac. - [Speaker 1] Okay, anybody else want to make a comment on what they preferentially use for in-flow?

- [Speaker 2] It depends what material you're going to use. If we use the vein, we go back to the common femoral, if we use prosthetic material, we would prefer to have a site where it's easier to go in and lower the risk of infection. - [Speaker 1] Right. I'll say that it depends on

the length, if I have enough length just to go deep femoral, I'll go deep femoral preferentially, but I have gone to the external iliac with a vein and have had no problem with kinking or anything, it would just make a tunnel lateral to the artery. We don't go medially because there are too many

branches there, but laterally, and you can do the anastomosis vein, and it only adds about two, three centimeters of length when you get it just above the inguinal ligament. With that, I'm going to thank the speakers, it was a great conference, and call the next moderators, please.

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