- I'd like to share with you our experience using tools to improve outcomes. These are my disclosures. So first of all we need to define the anatomy well using CTA and MRA and with using multiple reformats and 3D reconstructions. So then we can use 3D fusion with a DSA or with a flouro
or in this case as I showed in my presentation before you can use a DSA fused with a CT phase, they were required before. And also you can use the Integrated Registration like this, when you can use very helpful for the RF wire
because you can see where the RF wire starts and the snare ends. We can also use this for the arterial system. I can see a high grade stenosis in the Common iliac and you can use the 3D to define for your 3D roadmapping you can use on the table,
or you can use two methods to define the artery. Usually you can use the yellow outline to define the anatomy or the green to define the center. And then it's a simple case, 50 minutes, 50 minutes of ccs of contrast,
very simple, straightforward. Another everybody knows about the you know we can use a small amount of contrast to define the whole anatomy of one leg. However one thing that is relatively new is to use a 3D
in order to map, to show you the way out so you can do in this case here multiple segmental synosis, the drug-eluting-balloon angioplasty using the 3D roadmap as a reference. Also about this case using radial fre--
radial access to peripheral. Using a fusion of image you can see the outline of the artery. You can see where the high grade stenosis is with a minimum amount of contrast. You only use contrast when you are about
to do your angiogram or your angioplasty and after. And that but all everything else you use only the guide wires and cathers are advanced only used in image guidance without any contrast at all. We also been doing as I showed before the simultaneous injection.
So here I have two catheters, one coming from above, one coming from below to define this intravenous occlusion. Very helpful during through the and after the 3D it can be helpful. Like in this case when you can see this orange line is where
the RF wire is going to be advanced. As you can see the breathing, during the breathing cycle the pleura is on the way of the RF wire track. Pretty dangerous stuff. So this case what we did we asked the anesthesiologist
to have the patient in respiratory breath holding inspiration. We're able to hyperextend the lungs, cross with the RF wire without any complication. So very useful. And also you can use this outline yellow lines here
to define anatomy can help you to define where you need to put the stents. Make sure you're covering everything and having better outcomes at the end of the case without overexposure of radiation. And also at the end you can use the same volt of metric
reconstruction to check where you are, to placement of the stent and if you'd covered all the lesion that you had. The Cone beam CT can be used for also for the 3D model fusion. As you can see that you can use in it with fluoro as I
mentioned before you can do the three views in order to make sure that the vessels are aligned. And those are they follow when you rotate the table. And then you can have a pretty good outcome at the end of the day at of the case. In that case that potentially could be very catastrophic
close to the Supra aortic vessels. What about this case of a very dramatic, symptomatic varicose veins. We didn't know and didn't even know where to start in this case. We're trying to find our way through here trying to
understand what we needed to do. I thought we need to recanalize this with this. Did a 3D recan-- a spin and we saw ours totally off. This is the RFY totally interior and the snare as a target was posterior in the ASGUS.
Totally different, different plans. Eventually we found where we needed to be. We fused with the CAT scan, CT phase before, found the right spot and then were able to use
Integrated registration for the careful recanalization above the strip-- interiorly from the Supraaortic vessels. As you can see that's the beginning, that's the end. And also these was important to show us where we working.
We working a very small space between the sternal and the Supraaortic vessels using the RF wire. And this the only technology would allowed us to do this type of thing. Basically we created a percutaneous in the vascular stent bypass graft.
You can you see you use a curved RF wire to be able to go back to the snare. And that once we snare out is just conventional angioplasty recanalized with covered stents and pretty good outcome. On a year and a half follow-up remarkable improvement in this patient's symptoms.
Another patient with a large graft in the large swelling thigh, maybe graft on the right thigh with associated occlusion of the iliac veins and inclusion of the IVC and occlusion of the filter. So we did here is that we fused the maps of the arterial
phase and the venous phase and then we reconstruct in a 3D model. And doing that we're able to really understand the beginning of the problem and the end of the problem above the filter and the correlation with the arteries. So as you can see,
the these was very tortuous segments. We need to cross with the RF wire close to the iliac veins and then to the External iliac artery close to the Common iliac artery. But eventually we were able to help find a track. Very successfully,
very safe and then it's just convention technique. We reconstructed with covered stents. This is predisposed, pretty good outcome. As you can see this is the CT before, that's the CT after the swelling's totally gone
and the stents are widely open. So in conclusion these techniques can help a reduction of radiation exposure, volume of contrast media, lower complication, lower procedure time.
In other words can offer higher value in patient care. Thank you.
- We are talking about the current management of bleeding hemodialysis fistulas. I have no relevant disclosures. And as we can see there with bleeding fistulas, they can occur, you can imagine that the patient is getting access three times a week so ulcerations can't develop
and if they are not checked, the scab falls out and you get subsequent bleeding that can be fatal and lead to some significant morbidity. So fatal vascular access hemorrhage. What are the causes? So number one is thinking about
the excessive anticoagulation during dialysis, specifically Heparin during the dialysis circuit as well as with cumin and Xarelto. Intentional patient manipulati we always think of that when they move,
the needles can come out and then you get subsequent bleeding. But more specifically for us, we look at more the compromising integrity of the vascular access. Looking at stenosis, thrombosis, ulceration and infection. Ellingson and others in 2012 looked at the experience
in the US specifically in Maryland. Between the years of 2000/2006, they had a total of sixteen hundred roughly dialysis death, due to fatal vascular access hemorrhage, which only accounted for about .4% of all HD or hemodialysis death but the majority did come
from AV grafts less so from central venous catheters. But interestingly that around 78% really had this hemorrhage at home so it wasn't really done or they had experienced this at the dialysis centers. At the New Zealand experience and Australia, they had over a 14 year period which
they reviewed their fatal vascular access hemorrhage and what was interesting to see that around four weeks there was an inciting infection preceding the actual event. That was more than half the patients there. There was some other patients who had decoags and revisional surgery prior to the inciting event.
So can the access be salvaged. Well, the first thing obviously is direct pressure. Try to avoid tourniquet specifically for the patients at home. If they are in the emergency department, there is obviously something that can be done.
Just to decrease the morbidity that might be associated with potential limb loss. Suture repairs is kind of the main stay when you have a patient in the emergency department. And then depending on that, you decide to go to the operating room.
Perera and others 2013 and this is an emergency department review and emergency medicine, they use cyanoacrylate to control the bleeding for very small ulcerations. They had around 10 patients and they said that they had pretty good results.
But they did not look at the long term patency of these fistulas or recurrence. An interesting way to kind of manage an ulcerated bleeding fistula is the Limberg skin flap by Pirozzi and others in 2013 where they used an adjacent skin flap, a rhomboid skin flap
and they would get that approximal distal vascular control, rotate the flap over the ulcerated lesion after excising and repairing the venotomy and doing the closure. This was limited to only ulcerations that were less than 20mm.
When you look at the results, they have around 25 AV fistulas, around 15 AV grafts. The majority of the patients were treated with percutaneous angioplasty at least within a week of surgery. Within a month, their primary patency was running 96% for those fistulas and around 80% for AV grafts.
If you look at the six months patency, 76% were still opened and the fistula group and around 40% in the AV grafts. But interesting, you would think that rotating an adjacent skin flap may lead to necrosis but they had very little necrosis
of those flaps. Inui and others at the UC San Diego looked at their experience at dialysis access hemorrhage, they had a total 26 patients, interesting the majority of those patients were AV grafts patients that had either bovine graft
or PTFE and then aneurysmal fistulas being the rest. 18 were actually seen in the ED with active bleeding and were suture control. A minor amount of patients that did require tourniquet for a shock. This is kind of the algorithm when they look at
how they approach it, you know, obviously secure your proximal di they would do a Duplex ultrasound in the OR to assess hat type of procedure
they were going to do. You know, there were inciting events were always infection so they were very concerned by that. And they would obviously excise out the skin lesion and if they needed interposition graft replacement they would use a Rifampin soak PTFE
as well as Acuseal for immediate cannulation. Irrigation of the infected site were also done and using an impregnated antibiotic Vitagel was also done for the PTFE grafts. They were really successful in salvaging these fistulas and grafts at 85% success rate with 19 interposition
a patency was around 14 months for these patients. At UCS, my kind of approach to dealing with these ulcerated fistulas. Specifically if they bleed is to use
the bovine carotid artery graft. There's a paper that'll be coming out next month in JVS, but we looked at just in general our experience with aneurysmal and primary fistula creation with an AV with the carotid graft and we tried to approach these with early access so imagine with
a bleeding patient, you try to avoid using catheter if possible and placing the Artegraft gives us an opportunity to do that and with our data, there was no significant difference in the patency between early access and the standardized view of ten days on the Artegraft.
Prevention of the Fatal Vascular Access Hemorrhages. Important physical exam on a routine basis by the dialysis centers is imperative. If there is any scabbing or frank infection they should notify the surgeon immediately. Button Hole technique should be abandoned
even though it might be easier for the patient and decreased pain, it does increase infection because of that tract The rope ladder technique is more preferred way to avoid this. In the KDOQI guidelines of how else can we prevent this,
well, we know that aneurysmal fistulas can ulcerate so we look for any skin that might be compromised, we look for any risk of rupture of these aneurysms which rarely occur but it still needs to taken care of. Pseudoaneurysms we look at the diameter if it's twice the area of the graft.
If there is any difficulty in achieving hemostasis and then any obviously spontaneous bleeding from the sites. And the endovascular approach would be to put a stent graft across the pseudoaneurysms. Shah and others in 2012 had 100% immediate technical success They were able to have immediate access to the fistula
but they did have around 18.5% failure rate due to infection and thrombosis. So in conclusion, bleeding to hemodialysis access is rarely fatal but there are various ways to salvage this and we tried to keep the access viable for these patients.
Prevention is vital and educating our patients and dialysis centers is key. Thank you.
- I want to thank the organizers for putting together such an excellent symposium. This is quite unique in our field. So the number of dialysis patients in the US is on the order of 700 thousand as of 2015, which is the last USRDS that's available. The reality is that adrenal disease is increasing worldwide
and the need for access is increasing. Of course fistula first is an important portion of what we do for these patients. But the reality is 80 to 90% of these patients end up starting with a tunneled dialysis catheter. While placement of a tunneled dialysis catheter
is considered fairly routine, it's also clearly associated with a small chance of mechanical complications on the order of 1% at least with bleeding or hema pneumothorax. And when we've looked through the literature, we can notice that these issues
that have been looked at have been, the literature is somewhat old. It seemed to be at variance of what our clinical practice was. So we decided, let's go look back at our data. Inpatients who underwent placement
of a tunneled dialysis catheter between 1998 and 2017 reviewed all their catheters. These are all inpatients. We have a 2,220 Tesio catheter places, in 1,400 different patients. 93% of them placed on the right side
and all the catheters were placed with ultrasound guidance for the puncture. Now the puncture in general was performed with an 18 gauge needle. However, if we notice that the vein was somewhat collapsing with respiratory variation,
then we would use a routinely use a micropuncture set. All of the patients after the procedures had chest x-ray performed at the end of the procedure. Just to document that everything was okay. The patients had the classic risk factors that you'd expect. They're old, diabetes, hypertension,
coronary artery disease, et cetera. In this consecutive series, we had no case of post operative hemo or pneumothorax. We had two cut downs, however, for arterial bleeding from branches of the external carotid artery that we couldn't see very well,
and when we took out the dilator, patient started to bleed. We had three patients in the series that had to have a subsequent revision of the catheter due to mal positioning of the catheter. We suggest that using modern day techniques
with ultrasound guidance that you can minimize your incidents of mechanical complications for tunnel dialysis catheter placement. We also suggest that other centers need to confirm this data using ultrasound guidance as a routine portion of the cannulation
of the internal jugular veins. The KDOQI guidelines actually do suggest the routine use of duplex ultrasonography for placement of tunnel dialysis catheters, but this really hasn't been incorporated in much of the literature outside of KDOQI.
We would suggest that it may actually be something that may be worth putting into the surgical critical care literature also. Now having said that, not everything was all roses. We did have some cases where things didn't go
so straight forward. We want to drill down a little bit into this also. We had 35 patients when we put, after we cannulated the vein, we can see that it was patent. If it wasn't we'd go to the other side
or do something else. But in 35%, 35 patients, we can put the needle into the vein and get good flashback but the wire won't go down into the central circulation.
Those patients, we would routinely do a venogram, we would try to cross the lesion if we saw a lesion. If it was a chronically occluded vein, and we weren't able to cross it, we would just go to another site. Those venograms, however, gave us some information.
On occasion, the vein which is torturous for some reason or another, we did a venogram, it was torturous. We rolled across the vein and completed the procedure. In six of the patients, the veins were chronically occluded
and we had to go someplace else. In 20 patients, however, they had prior cannulation in the central vein at some time, remote. There was a severe stenosis of the intrathoracic veins. In 19 of those cases, we were able to cross the lesion in the central veins.
Do a balloon angioplasty with an 8 millimeter balloon and then place the catheter. One additional case, however, do the balloon angioplasty but we were still not able to place the catheter and we had to go to another site.
Seven of these lesions underwent balloon angioplasty of the innominate vein. 11 of them were in the proximal internal jugular vein, and two of them were in the superior vena cava. We had no subsequent severe swelling of the neck, arm, or face,
despite having a stenotic vein that we just put a catheter into, and no subsequent DVT on duplexes that were obtained after these procedures. Based on these data, we suggest that venous balloon angioplasty can be used in these patients
to maintain the site of an access, even with the stenotic vein that if your wire doesn't go down on the first pass, don't abandon the vein, shoot a little dye, see what the problem is,
and you may be able to use that vein still and maintain the other arm for AV access or fistular graft or whatever they need. Based upon these data, we feel that using ultrasound guidance should be a routine portion of these procedures,
and venoplasty should be performed when the wire is not passing for a central vein problem. Thank you.
- Thank you chairman, ladies and gentlemen. I have no conflict of interest for this talk. So, basically for vTOS we have the well known treatment options. Either the conservative approach with DOAC or anticoagulation for three months or longer supported by elastic stockings.
And alternatively there's the invasive approach with catheter thrombolysis and decompression surgery and as we've just heard in the talk but Ben Jackson, also in surgeons preference, additional PTA and continuation or not of anticoagulation.
And basically the chosen therapy is very much based on the specific specialist where the patient is referred to. Both treatment approaches have their specific complications. Rethrombosis pulmonary embolism,
but especially the post-thrombotic syndrome which is reported in conservative treatment in 26 up to 66%, but also in the invasive treatment approach up to 25%. And of course there are already well known complications related to surgery.
The problem is, with the current evidence, that it's only small retrospective studies. There is no comparative studies and especially no randomized trials. So basically there's a lack of high quality evidence leading to varying guideline recommendations.
And I'm not going through them in detail 'cause it's a rather busy slide. But if you take a quick look then you can see some disparencies between the different guidelines and at some aspects there is no recommendation at all,
or the guidelines refer to selected patients, but they define how they should be selected. So again, the current evidence is insufficient to determine the most clinically and cost effective treatment approach, and we believe that a randomized trial is warranted.
And this is the UTOPIA trial. And I'm going to take you a bit through the design. So the research question underline this trial is, does surgical treatment, consisting of catheter directed thrombolysis and first rib section, significantly reduce post-thrombotic syndrome
occurrence, as compared to conservative therapy with DOAC anticoagulation, in adults with primary upper extremity deep vein thrombosis? The design is multicenter randomized and the population is all adults with first case of primary Upper Extremity
Deep Venous Thrombosis. And our primary outcome is occurrence of post-thrombotic syndrome, and this the find according the modified Villalta score. And there are several secondary outcomes, which of course we will take into account,
such as procedural complications, but also quality of life. This is the trial design. Inclusion informed consent and randomization are performed at first presentation either with the emergency department or outpatient clinic.
When we look at patients 18 years or older and the symptoms should be there for less than 14 days. Exclusion criteria are relevant when there's a secondary upper extremity deep vein thrombosis or any contra-indication for DOACs or catheter directed thrombolysis.
We do perform imaging at baseline with a CT venography. We require this to compare baseline characteristics of both groups to mainly determine what the underlying cause of the thrombosis being either vTOS or idiopathic.
And then a patient follows the course of the trial either the invasive treatment with decompression surgery and thrombolysis and whether or not PTA is required or not, or conservative treatment and we have to prefer DOAC Rivaroxaban or apixaban to be used.
Further down the patient is checked for one month and the Villalta score is adapted for use in the upper extremity and we also apply quality of life scores and scores for cost effectiveness analysis. And this is the complete flowchart of the whole trial.
Again, very busy slide, but just to show you that the patient is followed up at several time points, one, three, six, and 12 months and the 12 months control is actually the endpoint of the trial
And then again, a control CT venography is performed. Sample size and power calculation. We believe that there's an effect size of 20% reduction in post-thrombotic syndrome in favor of the invasive treatment and there's a two-side p-value of 0.05
and at 80% power, we consider that there will be some loss to follow up, and therefore we need just over 150 patients to perform this trial. So, in short, this slide more or less summarize it. It shows the several treatment options
that are available for these patients with Upper Extremity Venous Thrombosis. And in the trial we want to see, make this comparison to see if anticoagulation alone is as best as invasive therapy. I thank for your attention.
- Talk to you a little bit about again a major paradigm shift in AVMs which is the retrograde vein approach. I mean I think the biggest benefit and the biggest change that we've seen has been in the Yakes classification the acknowledgment
and understanding that the safety, efficacy and cure rate for AVMs is essentially 100% in certain types of lesions where the transvenous approach is not only safer, but easier and far more effective. So, it's the Yakes classification
and we're talking about a variety of lesions including Yakes one, coils and plugs. Two A the classic nidus. Three B single outflow vein. And we're talking now about these type of lesions. Three A aneurysmal vein single outflow.
Three B multiple outflows and diffuse. This is what I personally refer to as venous predominant lesions. And it's these lesions which I think have yielded the most gratifying and most dramatic results. Close to 100% cure if done properly
and that's the Yakes classification and that's really what it's given us to a great degree. So, Yakes one has been talked about, not a problem put a plus in it it's just an artery to vein.
We all know how to do that. That's pulmonary AVM or other things. Yakes two B however, is a nidus is still present but there is a single outflow aneurysmal vein. And there are two endovascular approaches. Direct puncture, transarterial,
but transvenous retrograde or direct puncture of the vein aneurism with the coil, right. You got to get to the vein, and the way to get to the vein is either by directly puncturing which is increasingly used, but occasionally transvenous. So, here's an example I showed a similar one before,
as I said I think some of these are post phlebitic but they represent the archetype of this type of lesion a two B where coil embolization results in cure, durable usually one step sometimes a little more. In the old days we used to do multiple
arterial injections, we now know that that's not necessary. This is this case I showed earlier. I think the thing I want to show here is the nature of the arteriovenous connection. Notice the nidus there just on this side of the
vein wall with a single venous outflow, and this can of course be cured by puncture, there's the needle coming in. And interestingly these needles can be placed in any way. Wayne and I have talked about this.
I've gone through the bladder under ultrasound guidance, I've gone from behind and whatever access you can get that's safe, as long as you can get a needle into it an 18 gauge needle, blow coils in you get a little tired, and you're there a long time putting in
coils and guide wires and so on. But the cures are miraculous, nothing short of miraculous. And many of these patients are patients who have been treated inappropriately in the past and have had very poor outcomes,
and they can be cured. And that a three year follow-up. The transcatheter retrograde vein is occasionally available. Here's an example of an acquired but still an AVM an acquired AVM
of the uterus where you see the venous filling on the left, lots of arteries. This cannot be treated with the arterial approach folks. So, this one happened to be available
and I was having fun with it as well, which is through the contralateral vein in and I was able to catheterize that coil embolization, cured so. Three A is a slightly different variant but it's important it is different.
Multiple in-flow arteries into an aneurysmal vein wall. And the important identification Wayne has given us is that the vein wall itself is the nidus and there's a single out-flow vein. So, once again, attacking the vein wall by destroying the vein, packing
and thrombosing that nidus. I think it's a combination of compression and thrombosis can often be curative. A few examples of that this was shown earlier, this is from Dr. Yake's experience but it's a beautiful example
and we try to give you the best examples of a singular type of lesion so you understand the anatomy. That's the sequential and now you see single out-flow vein. How do you treat this?
Coil embolization, direct puncture and ultimately a cure. And that's the arteriogram. Cured. And I think it's a several year follow-up two or three year follow-up on this one.
So a simple lesion, but illustrative of what we're trying to do here. A foot AVM with a single out-flow vein, this is cured by a combination of direct puncture right at the vein. And you know I would say that the beauty of
venous approach is actually something which it isn't widely acknowledged, which is the safety element. Let's say you're wrong, let's say you're treating an AVM and you think okay I'm going to attack
from the vein side, well, if you're not successful from the vein side, you've lost nothing. The risk in all of these folks is, if you're in the artery and you don't understand that the artery is feeding significant tissue,
these are where all the catastrophic, disastrous complications you've heard so much about have occurred. It's because the individuals do not understand that they're in a nutrient artery. So, when in doubt direct puncture
and stay on the venous side. You can't hurt yourself with ethanol and that's why ethanol is as safe as it is when it's used properly. So, three B finally is multiple in-flow arteries/arterioles shunting into an aneurysmal vein
this is multiple out-flow veins. So direct puncture, coils into multiple veins multiple sessions. So, here's an example of that. This is with alcohol this is a gentleman I saw with a bad ulcer,
and this looks impossible correct? But look at the left hand arteriogram, you can see the filling of veins. Look at the right hand in a slight oblique. The answer here is to puncture that vein. Where do we have our coil.
The answer is to puncture here, and this is thin tissue, but we're injecting there. See we're right at the vein, right here and this is a combination arteriogram. Artery first, injection into the vein.
Now we're at the (mumbles), alcohol is repeatedly placed into this, and you can see that we're actually filling the nidus here. See here. There's sclerosis beginning destruction of the vein
with allowing the alcohol to go into the nidus and we see progressive healing and ultimately resolution of the ulcer. So, a very complex lesion which seemingly looks impossible is cured by alcohol in an out-flow vein.
So the Yakes classification of AVMs is the only one in which architecture inform treatment and produces consistent cures. And venous predominant lesions, as I've shown you here, are now curable in a high percentage of cases
when the underlying anatomy is understood and the proper techniques are chosen. Thanks very much.
- Mr. Chairman, ladies and gentlemen, good morning. I'd like to thank Dr. Veith for the opportunity to present at this great meeting. I have nothing to disclose. Since Dr. DeBakey published the first paper 60 years ago, the surgical importance of deep femoral artery has been well investigated and documented.
It can be used as a reliable inflow for low extremity bypass in certain circumstances. To revascularize the disease, the deep femoral artery can improve rest pain, prevent or delay the amputation, and help to heal amputation stump.
So, in this slide, the group patient that they used deep femoral artery as a inflow for infrainguinal bypass. And 10-year limb salvage was achieved in over 90% of patients. So, different techniques and configurations
of deep femoral artery angioplasty have been well described, and we've been using this in a daily basis. So, there's really not much new to discuss about this. Next couple minutes, I'd like to focus on endovascular invention 'cause I lot I think is still unclear.
Dr. Bath did a systemic review, which included 20 articles. Nearly total 900 limbs were treated with balloon angioplasty with or without the stenting. At two years, the primary patency was greater than 70%. And as you can see here, limb salvage at two years, close to, or is over 98% with very low re-intervention rate.
So, those great outcomes was based on combined common femoral and deep femoral intervention. So what about isolated deep femoral artery percutaneous intervention? Does that work or not? So, this study include 15 patient
who were high risk to have open surgery, underwent isolated percutaneous deep femoral artery intervention. As you can see, at three years, limb salvage was greater than 95%. The study also showed isolated percutaneous transluminal
angioplasty of deep femoral artery can convert ischemic rest pain to claudication. It can also help heal the stump wound to prevent hip disarticulation. Here's one of my patient. As you can see, tes-tee-lee-shun with near
or total occlusion of proximal deep femoral artery presented with extreme low-extremity rest pain. We did a balloon angioplasty. And her ABI was increased from 0.8 to 0.53, and rest pain disappeared. Another patient transferred from outside the facility
was not healing stump wound on the left side with significant disease as you can see based on the angiogram. We did a hybrid procedure including stenting of the iliac artery and the open angioplasty of common femoral artery and the profunda femoral artery.
Significantly improved the perfusion to the stump and healed wound. The indications for isolated or combined deep femoral artery revascularization. For those patient presented with disabling claudication or rest pain with a proximal
or treatable deep femoral artery stenosis greater than 50% if their SFA or femoral popliteal artery disease is unsuitable for open or endovascular treatment, they're a high risk for open surgery. And had the previous history of multiple groin exploration, groin wound complications with seroma or a fungal infection
or had a muscle flap coverage, et cetera. And that this patient should go to have intervascular intervention. Or patient had a failed femoral pop or femoral-distal bypass like this patient had, and we should treat this patient.
So in summary, open profundaplasty remains the gold standard treatment. Isolated endovascular deep femoral artery intervention is sufficient for rest pain. May not be good enough for major wound healing, but it will help heal the amputation stump
to prevent hip disarticulation. Thank you for much for your attention.
- Thank you, chairman. Good afternoon, ladies and gentlemen. I've not this conflict of interest on this topic. So, discussion about double-layer stent has been mainly focused about the incidence of new lesions, chemical lesions after the stenting, and because there are still some issue
about the plaque prolapse, this has still has been reduced in a comparison to conventional stent that's still present. We started our study two years ago to evaluate on two different set of population of a patient who underwent stent, stenting,
to see if there is any different between the result of two stents, Cguard from Inspire, and Roadsaver from Terumo in term of ischemic lesion and if there is a relationship between the activity of the plaque evaluated with the MRI
and new ischemic lesion after the procedure. So, the population was aware of similar what we found, and that there's no difference between the two stent we have had, and new ischemic lesions is, there's a 38%, for a total amount of 34 lesions,
and ipsilateral in 82% of cases. The most part of the lesion appeared at the 24 hours, for the 88.2% of cases, while only the 12% of cases, we have a control at our lesion. According to the DWI, we have seen that
the DWI of the plaque is positive, or there is an activity of the plaque. There's a higher risk of embolization with a high likelihood or a risk of 6.25%. But, in the end, what we learned in the beginning, what there have known,
there's no difference in the treatment of the carotid stenosis with this device, and the plaque activity, when positive at the DWI MR, is a predictive for a higher risk of new ischemic lesions at 24 hours. But, what we are still missing in terms of information,
where something about the patency of the stents at mid-term follow-up, and the destiny of external carotid artery at mid-term follow-up. Alright, we have to say we have an occlusion transitory, occlusion of the semi-carotid artery
immediately after the deployment of the Terumo stent. The ECA recovery completely. But in, what we want to check, what could happen, following the patient in the next year. So, we perform a duplicate ultrasound, at six, at 12, and 24 months after the procedure,
in order to re-evaluate the in-stent restenosis and then, if there was a new external carotid artery stenosis or occlusion. We have made this evaluation according to the criteria of grading of carotid in-stent restenosis proposed on Stroke by professors attache group.
And what we found that we are an incidence of in-stent restenosis of 10%, of five on 50 patient, one at six month and four at one year. And we are 4% of external carotid artery new stenosis. All in two patient, only in the Roadsaver group.
We are three in-stent restenosis for Roadsaver, two in-stent restenosis for Cguard, and external new stenosis only in the Roadsaver group. And this is a case of Roadsaver stent in-stent restenosis of 60% at one year. Two year follow-up,
so we compare what's happening for Cguard and Roadsaver. We see that no relation have been found with the plaque activity or the device. If we check our result, even if this is a small series, we both reported in the literature for the conventional stent,
we've seen that in our personal series, with the 10% of in-stent restenosis, that it's consistent with what's reported for conventional CAS. And the same we found when we compared our result with the result reported for CAS with conventional stent.
So in our personal series, we had not external carotid artery occlusion. We have 4% instance, and for stenosis while with conventional CAS, occlusion of external carotid artery appear in 3.8% of cases.
So, what can we add to our experience now in the incidence, if, I'm sorry, if confirmed by larger count of patient and longer study? We can say that the incidence of in-stent restenosis for this new double-layer stent and the stenosis on the external carotid artery,
if not the different for all, with what reported for conventional stent. Thank you.
- Thank you. I have two talks because Dr. Gaverde, I understand, is not well, so we- - [Man] Thank you very much. - We just merged the two talks. All right, it's a little joke. For today's talk we used fusion technology
to merge two talks on fusion technology. Hopefully the rest of the talk will be a little better than that. (laughs) I think we all know from doing endovascular aortic interventions
that you can be fooled by the 2D image and here's a real life view of how that can be an issue. I don't think I need to convince anyone in this room that 3D fusion imaging is essential for complex aortic work. Studies have clearly shown it decreases radiation,
it decreases fluoro time, and decreases contrast use, and I'll just point out that these data are derived from the standard mechanical based systems. And I'll be talking about a cloud-based system that's an alternative that has some advantages. So these traditional mechanical based 3D fusion images,
as I mentioned, do have some limitations. First of all, most of them require manual registration which can be cumbersome and time consuming. Think one big issue is the hardware based tracking system that they use. So they track the table rather than the patient
and certainly, as the table moves, and you move against the table, the patient is going to move relative to the table, and those images become unreliable. And then finally, the holy grail of all 3D fusion imaging is the distortion of pre-operative anatomy
by the wires and hardware that are introduced during the course of your procedure. And one thing I'd like to discuss is the possibility that deep machine learning might lead to a solution to these issues. How does 3D fusion, image-based 3D fusion work?
Well, you start, of course with your pre-operative CT dataset and then you create digitally reconstructed radiographs, which are derived from the pre-op CTA and these are images that resemble the fluoro image. And then tracking is done based on the identification
of two or more vertebral bodies and an automated algorithm matches the most appropriate DRR to the live fluoro image. Sounds like a lot of gobbledygook but let me explain how that works. So here is the AI machine learning,
matching what it recognizes as the vertebral bodies from the pre-operative CT scan to the fluoro image. And again, you get the CT plus the fluoro and then you can see the overlay with the green. And here's another version of that or view of that.
You can see the AI machine learning, identifying the vertebral bodies and then on your right you can see the fusion image. So just, once again, the AI recognizes the bony anatomy and it's going to register the CT with the fluoro image. It tracks the patient, not the table.
And the other thing that's really important is that it recognizes the postural change that the patient undergoes between the posture during the CT scan, versus the posture on the OR table usually, or often, under general anesthesia. And here is an image of the final overlay.
And you can see the visceral and renal arteries with orange circles to identify them. You can remove those, you can remove any of those if you like. This is the workflow. First thing you do is to upload the CT scan to the cloud.
Then, when you're ready to perform the procedure, that is downloaded onto the medical grade PC that's in your OR next to your fluoro screen, and as soon as you just step on the fluoro pedal, the CYDAR overlay appears next to your, or on top of your fluoro image,
next to your regular live fluoro image. And every time you move the table, the computer learning recognizes that the images change, and in a couple of seconds, it replaces with a new overlay based on the obliquity or table position that you have. There are some additional advantages
to cloud-based technology over mechanical technology. First of all, of course, or hardware type technology. Excuse me. You can upgrade it in real time as opposed to needing intermittent hardware upgrades. Works with any fluoro equipment, including a C-arm,
so you don't have to match your 3D imaging to the brand of your fluoro imaging. And there's enhanced accuracy compared to mechanical registration systems as imaging. So what are the clinical applications that this can be utilized for?
Fluoroscopy guided endovascular procedures in the lower thorax, abdomen, and pelvis, so that includes EVAR and FEVAR, mid distal TEVAR. At present, we do need two vertebral bodies and that does limit the use in TEVAR. And then angioplasty stenting and embolization
of common iliac, proximal external and proximal internal iliac artery. Anything where you can acquire a vertebral body image. So here, just a couple of examples of some additional non EVAR/FEVAR/TEVAR applications. This is, these are some cases
of internal iliac embolization, aortoiliac occlusion crossing, standard EVAR, complex EVAR. And I think then, that the final thing that I'd like to talk about is the use with C-arm, which is think is really, extremely important.
Has the potential to make a very big difference. All of us in our larger OR suites, know that we are short on hybrid availability, and yet it's difficult to get our institutions to build us another hybrid room. But if you could use a high quality 3D fusion imaging
with a high quality C-arm, you really expand your endovascular capability within the operating room in a much less expensive way. And then if you look at another set of circumstances where people don't have a hybrid room at all, but do want to be able to offer standard EVAR
to their patients, and perhaps maybe even basic FEVAR, if there is such a thing, and we could use good quality imaging to do that in the absence of an actual hybrid room. That would be extremely valuable to be able to extend good quality care
to patients in under-served areas. So I just was mentioning that we can use this and Tara Mastracci was talking yesterday about how happy she is with her new room where she has the use of CYDAR and an excellent C-arm and she feels that she is able to essentially run two rooms,
two hybrid rooms at once, using the full hybrid room and the C-arm hybrid room. Here's just one case of Dr. Goverde's. A vascular case that he did on a mobile C-arm with aortoiliac occlusive disease and he places kissing stents
using a CYDAR EV and a C-arm. And he used five mils of iodinated contrast. So let's talk about a little bit of data. This is out of Blain Demorell and Tara Mastrachi's group. And this is use of fusion technology in EVAR. And what they found was that the use of fusion imaging
reduced air kerma and DSA runs in standard EVAR. We also looked at our experience recently in EVAR and FEVAR and we compared our results. Pre-availability of image based fusion CT and post image based fusion CT. And just to clarify,
we did have the mechanical product that Phillip's offers, but we abandoned it after using it a half dozen times. So it's really no image fusion versus image fusion to be completely fair. We excluded patients that were urgent/emergent, parallel endographs, and IBEs.
And we looked at radiation exposure, contrast use, fluoro time, and procedure time. The demographics in the two groups were identical. We saw a statistically significant decrease in radiation dose using image based fusion CT. Statistically a significant reduction in fluoro time.
A reduction in contrast volume that looks significant, but was not. I'm guessing because of numbers. And a significantly different reduction in procedure time. So, in conclusion, image based 3D fusion CT decreases radiation exposure, fluoro time,
and procedure time. It does enable 3D overlays in all X-Ray sets, including mobile C-arm, expanding our capabilities for endovascular work. And image based 3D fusion CT has the potential to reduce costs
and improve clinical outcomes. Thank you.
- Thank you so much. We have no disclosures. So I think everybody would agree that the transposed basilic vein fistula is one of the most important fistulas that we currently operate with. There are many technical considerations
related to the fistula. One is whether to do one or two stage. Your local criteria may define how you do this, but, and some may do it arbitrarily. But some people would suggest that anything less than 4 mm would be a two stage,
and any one greater than 4 mm may be a one stage. The option of harvesting can be open or endovascular. The option of gaining a suitable access site can be transposition or superficialization. And the final arterial anastomosis, if you're not superficializing can either be
a new arterial anastomosis or a venovenous anastomosis. For the purposes of this talk, transposition is the dissection, transection and re tunneling of the basilic vein to the superior aspect of the arm, either as a primary or staged procedure. Superficialization is the dissection and elevation
of the basilic vein to the superior aspect of the upper arm, which may be done primarily, but most commonly is done as a staged procedure. The natural history of basilic veins with regard to nontransposed veins is very successful. And this more recent article would suggest
as you can see from the upper bands in both grafts that either transposed or non-transposed is superior to grafts in current environment. When one looks at two-stage basilic veins, they appear to be more durable and cost-effective than one-stage procedures with significantly higher
patency rates and lower rates of failure along comparable risk stratified groups from an article from the Journal of Vascular Surgery. Meta-ana, there are several meta-analysis and this one shows that between one and two stages there is really no difference in the failure and the patency rates.
The second one would suggest there is no overall difference in maturation rate, or in postoperative complication rates. With the patency rates primary assisted or secondary comparable in the majority of the papers published. And the very last one, again based on the data from the first two, also suggests there is evidence
that two stage basilic vein fistulas have higher maturation rates compared to the single stage. But I think that's probably true if one really realizes that the first stage may eliminate a lot of the poor biology that may have interfered with the one stage. But what we're really talking about is superficialization
versus transposition, which is the most favorite method. Or is there a favorite method? The early data has always suggested that transposition was superior, both in primary and in secondary patency, compared to superficialization. However, the data is contrary, as one can see,
in this paper, which showed the reverse, which is that superficialization is much superior to transposition, and in the primary patency range quite significantly. This paper reverses that theme again. So for each year that you go to the Journal of Vascular Surgery,
one gets a different data set that comes out. The final paper that was published recently at the Eastern Vascular suggested strongly that the second stage does consume more resources, when one does transposition versus superficialization. But more interestingly also found that these patients
who had the transposition had a greater high-grade re-stenosis problem at the venovenous or the veno-arterial anastomosis. Another point that they did make was that superficialization appeared to lead to faster maturation, compared to the transposition and thus they favored
superficialization over transposition. If one was to do a very rough meta-analysis and take the range of primary patencies and accumulative patencies from those papers that compare the two techniques that I've just described. Superficialization at about 12 months
for its primary patency will run about 57% range, 50-60 and transposition 53%, with a range of 49-80. So in the range of transposition area, there is a lot of people that may not be a well matched population, which may make meta-analysis in this area somewhat questionable.
But, if you get good results, you get good results. The cumulative patency, however, comes out to be closer in both groups at 78% for superficialization and 80% for transposition. So basilic vein transposition is a successful configuration. One or two stage procedures appear
to carry equally successful outcomes when appropriate selection criteria are used and the one the surgeon is most favored to use and is comfortable with. Primary patency of superficialization despite some papers, if one looks across the entire literature is equivalent to transposition.
Cumulative patency of superficialization is equivalent to transposition. And there is, appears to be no apparent difference in complications, maturation, or access duration. Thank you so much.
- Thanks Fieres. Thank you very much for attending this session and Frank for the invitation. These are my disclosures. We have recently presented the outcomes of the first 250 patients included in this prospective IDE at the AATS meeting in this hotel a few months ago.
In this study, there was no in-hospital mortality, there was one 30-day death. This was a death from a patient that had intracranial hemorrhage from the spinal drain placement that eventually was dismissed to palliative care
and died on postoperative day 22. You also note that there are three patients with paraplegia in this study, one of which actually had a epidural hematoma that was led to various significant and flacid paralysis. That prompted us to review the literature
and alter our outcomes with spinal drainage. This review, which includes over 4700 patients shows that the average rate of complications is 10%, some of those are relatively moderate or minor, but you can see a rate of intracranial hemorrhage of 1.5% and spinal hematoma of 1% in this large review,
which is essentially a retrospective review. We have then audited our IDE patients, 293 consecutive patients treated since 2013. We looked at all their spinal drains, so there were 240 placement of drains in 187 patients. You can see that some of these were first stage procedures
and then the majority of them were the index fenestrated branch procedure and some, a minority were Temporary Aneurysm Sac Perfusions. Our rate of complication was identical to the review, 10% and I want to point out some of the more important complications.
You can see here that intracranial hypotension occurred in 6% of the patients, that included three patients, or 2%, with intracranial hemorrhage and nine patients, or 5%, with severe headache that prolonged hospital stay and required blood patch for management.
There were also six patients with spinal hematomas for a overall rate of 3%, including the patient that I'll further discuss later. And one death, which was attributed to the spinal drain. When we looked at the intracranial hypotension in these 12 patients, you can see
the median duration of headache was four days, it required narcotics in seven patients, blood patch in five patients. All these patients had prolonged hospital stay, in one case, the prolongation of hospital stay was of 10 days.
Intracranial hemorrhage in three patients, including the patient that I already discussed. This patient had a severe intracranial hemorrhage which led to a deep coma. The patient was basically elected by the family to be managed with palliative care.
This patient end up expiring on postoperative day 21. There were other two patients with intracranial hemorrhage, one remote, I don't think that that was necessarily related to the spinal drain, nonetheless we had it on this review. These are some of the CT heads of the patients that had intracranial hemorrhage,
including the patient that passed away, which is outlined in the far left of your slide. Six patients had spinal hematoma, one of these patients was a patient, a young patient treated for chronic dissection. Patient evolved exceptionally well, moving the legs,
drain was removed on postoperative day two. As the patient is standed out of the bed, felt weakness in the legs, we then imaged the spine. You can see here, very severe spinal hematoma. Neurosurgery was consulted, decided to evacuate, the patient woke up with flacid paralysis
which has not recovered. There were two other patients with, another patient with paraplegia which was treated conservatively and improved to paraparesis and continues to improve and two other patients with paraparesis.
That prompted changes in our protocol. We eliminated spinal drains for Extent IVs, we eliminated for chronic dissection, in first stages, on any first stage, and most of the Extent IIIs, we also changed our protocol of drainage
from the routine drainage of a 10 centimeters of water for 15 minutes of the hours to a maximum of 20 mL to a drainage that's now guided by Near Infrared Spectroscopy, changes or symptoms. This is our protocol and I'll illustrate how we used this in one patient.
This is a patient that actually had this actual, exact anatomy. You can see the arch was very difficult, the celiac axis was patent and provided collateral flow an occluded SMA. The right renal artery was chronically occluded.
As we were doing this case the patient experienced severe changes in MEP despite the fact we had flow to the legs, we immediately stopped the procedure with still flow to the aneurysm sac. The patient develops pancreatitis, requires dialysis
and recovers after a few days in the ICU with no neurological change. Then I completed the repair doing a subcostal incision elongating the celiac axis and retrograde axis to this graft to complete the branch was very difficult to from the arm
and the patient recovered with no injury. So, in conclusion, spinal drainage is potentially dangerous even lethal and should be carefully weighted against the potential benefits. I think that our protocol now uses routine drainage for Extent I and IIs,
although I still think there is room for a prospective randomized trial even on this group and selective drainage for Extent IIIs and no drainage for Extent IVs. We use NIRS liberally to guide drainage and we use temporary sac perfusion
in those that have changes in neuromonitoring. Thank you very much.
- Good morning, thank you, Dr. Veith, for the invitation. My disclosures. So, renal artery anomalies, fairly rare. Renal ectopia and fusion, leading to horseshoe kidneys or pelvic kidneys, are fairly rare, in less than one percent of the population. Renal transplants, that is patients with existing
renal transplants who develop aneurysms, clearly these are patients who are 10 to 20 or more years beyond their initial transplantation, or maybe an increasing number of patients that are developing aneurysms and are treated. All of these involve a renal artery origin that is
near the aortic bifurcation or into the iliac arteries, making potential repair options limited. So this is a personal, clinical series, over an eight year span, when I was at the University of South Florida & Tampa, that's 18 patients, nine renal transplants, six congenital
pelvic kidneys, three horseshoe kidneys, with varied aorto-iliac aneurysmal pathologies, it leaves half of these patients have iliac artery pathologies on top of their aortic aneurysms, or in place of the making repair options fairly difficult. Over half of the patients had renal insufficiency
and renal protective maneuvers were used in all patients in this trial with those measures listed on the slide. All of these were elective cases, all were technically successful, with a fair amount of followup afterward. The reconstruction priorities or goals of the operation are to maintain blood flow to that atypical kidney,
except in circumstances where there were multiple renal arteries, and then a small accessory renal artery would be covered with a potential endovascular solution, and to exclude the aneurysms with adequate fixation lengths. So, in this experience, we were able, I was able to treat eight of the 18 patients with a fairly straightforward
endovascular solution, aorto-biiliac or aorto-aortic endografts. There were four patients all requiring open reconstructions without any obvious endovascular or hybrid options, but I'd like to focus on these hybrid options, several of these, an endohybrid approach using aorto-iliac
endografts, cross femoral bypass in some form of iliac embolization with an attempt to try to maintain flow to hypogastric arteries and maintain antegrade flow into that pelvic atypical renal artery, and a open hybrid approach where a renal artery can be transposed, and endografting a solution can be utilized.
The overall outcomes, fairly poor survival of these patients with a 50% survival at approximately two years, but there were no aortic related mortalities, all the renal artery reconstructions were patented last followup by Duplex or CT imaging. No aneurysms ruptures or aortic reinterventions or open
conversions were needed. So, focus specifically in a treatment algorithm, here in this complex group of patients, I think if the atypical renal artery comes off distal aorta, you have several treatment options. Most of these are going to be open, but if it is a small
accessory with multiple renal arteries, such as in certain cases of horseshoe kidneys, you may be able to get away with an endovascular approach with coverage of those small accessory arteries, an open hybrid approach which we utilized in a single case in the series with open transposition through a limited
incision from the distal aorta down to the distal iliac, and then actually a fenestrated endovascular repair of his complex aneurysm. Finally, an open approach, where direct aorto-ilio-femoral reconstruction with a bypass and reimplantation of that renal artery was done,
but in the patients with atypical renals off the iliac segment, I think you utilizing these endohybrid options can come up with some creative solutions, and utilize, if there is some common iliac occlusive disease or aneurysmal disease, you can maintain antegrade flow into these renal arteries from the pelvis
and utilize cross femoral bypass and contralateral occlusions. So, good options with AUIs, with an endohybrid approach in these difficult patients. Thank you.
- Thank you very much both. It was a great pleasure to see you. I continue to be grateful for the guidance you have given me over the years. Thank you to the organizers for advising me to speak. These are my disclosures. So really there are two questions posed by this topic.
One is, is the patent popliteal vein necessary? I would assume from this is it necessary for patency and symptom relief to be achieved in treating patients with both acute DVT and potentially chronic. And has the evolution formic mechanical therapy
led to over stenting. Which means we have to ask the question what is an appropriate rate for stenting. I am not sure we know the answer to that. So being able to answer over stenting requires us to know how many patients
actually need the stent in the first place in acute DVT treatments. The problem is essentially this. Is that when we form lithic therapies and this is a classic case of treatment formed with formic and mechanical device
but without a follow up using lithic in the patient for whom lithic was not feasible. You end up opening up a vessel but you can see from the image on the left hand side that there is a degree still of luminol contrast deficit suggesting some cult left behind
in the external iliac vein. Well there is obviously a May-Thurner legion at the top. The question of over stenting is one of do we just stent the May-Thruner and extend it down into the external iliac vein to trap that thrombus
or would a period of time of lithic have resulted in this clot resolving and not needed a stent at the end of it. To get to the question of how many people should be stented. The only way we can really do this
is try and exstipulate from the literature to some extent. This is the short and long term outcome from the Kevin study. Where there is ultrasound follow up of patients underwent standard treatment only.
And a additional group in the patients had catheter-directed thrombolysis. We can see there that the patients did six months in catheter-directed thrombolysis group is around 60%. And the patency seen with the non treated group
is around 40%. If we kind of use these numbers as a guide we probably expect therefore that the stent rate would be somewhere between 40 and 60 percent. To account for treating the outflow structure that presumably patients see at six months.
But this is clearly not a very rebost method of being absolutely clear on who needs stents. Additional method is we don't really have and answer for who should be stented at the end of a procedure. So if you look at the massive variability
in the other studies. We see that attract stent rate is approximately 28% for the study. Which is obviously a operative discretion and has been criticized for that reason. But there is no comment on the Popliteal vein
or Popliteal vein patency. Cavent did an stent rate of 15% again with no real comment on whether the Popliteal vein was open and it wasn't a prerequisite for treatment in the study. This contrast with the Ansberg Aspirex Registry.
Which is a registry of a purely mechanical device to aspirex clot and the stent rate is 100%. Baekgaard Copenhagen used a catered-directed thrombolysis with a mandated open popliteal vein for purpose to be in the study. He has a stent rate of 60%.
My own personal experience of 160 odd patients is that were stenting around 80% of patients with outflow legion at the end of treatment. And were not really bothered by whether the popliteal vein is clear or not. But that doesn't necessarily answer the question
whether it makes a difference in the long run. So its very difficult even looking at the data we have because there is no standard definition of what a outflow stenosis is. There is no objective measure for an outflow stenosis. So stenting becomes and operative discretion decision.
But you would have to say that if your taking purely mechanical devices and the stent rates are going up to 100% that the inclination would be that there is potential for formic mechanical therapy to lead to overstenting and increase use
for stents for sure. In our experience then we had 81 patients who had CDT alone verse 70 patients who had AngioJet Thrombectomy. The basic characteristics of the group are pretty much identical.
With similar ages and no difference between whether the thrombus with left side or right side of body or so on. And these are the patency curves for the different groups with equivalent primary, primary assisted and secondary patency over two yeas.
We had no difference in stent rates with the median stenting of 80% in both groups with two stents used in average for each of those patients. However in our practice AngioJet is rarely used alone. So we had 70 patients for whom AngioJet was used. 24 of those where AngioJet was used up front
as the first line of treatment followed by some CDT. We have tended find that if we wanted full clock clearance. We have always had omit to some extent. And single stage therapy is quite difficult to achieve unless you spent a lot of time in it.
Patency in the popliteal vein is clearly affected by some extent. These are our follow up results if we don't have a patent popliteal vein at the end. It does drop off in stent patency. So the conclusions then I think.
Is that patent popliteal vein is necessary for long term results. But you can still treat patients that have acute popliteal vein for larsons that is not a contraindication. Pure mechanical therapies may well lead to higher stent rate.
But is this a bad thing or a good thing? We don't really know this at this stage as to what the long term outcomes will be. Thank you very much.
- Thank you, good morning everybody. Thank you for the kind invitation, Professor Veith, it's an honor for me to be here again this year in New York. I will concentrate my talk about the technical issues and the experience in the data we have already published about the MISACE in more than 50 patients.
So I have no disclosure regarded to this topic. As you already heard, the MISACE means the occlusion of the main stem of several segmental arteries to preserve the capability of the collateral network to build new arteries. And as a result, we developed
the ischemic preconditioning of the spinal cord. Why is this so useful? Because it's an entirely endovascular first stage of a staged approach to treat thoracoabdominal aortic aneurysm in order to reduce the ischemic spinal cord injury.
How do you perform the MISACE? Basically, we perform the procedure in local anesthesia, through a percutaneous trans-femoral access using a small-bore sheath. The patient is awake, that means has no cerebrospinal fluid damage
so we can monitor the patient's neurological for at least 48 hours after the procedure. So, after the puncture of the common femoral artery, using a technique of "tower of power" in order to cannulate the segmental arteries. As you can see here, we started with a guiding catheter,
then we place a diagnosis catheter and inside, a microcatheter that is placed inside the segmental artery. Then we started occlusion of the ostial segment of the segmental artery. We use coils or vascular plugs.
We don't recommend the use of fluids due to the possible distal embolization and the consequences. Since we have started this procedure, we have gained a lot of experience and we have started to ask,
what is a sufficient coilembolization? As you can see here, this artery, we can see densely packed coils inside, but you can see still blood flowing after the coil. So, was it always occluding, or is it spontaneous revascularization?
That, we do not know yet. The question, is it flow reduction enough to have a ischemic precondition of the spinal cord? Another example here, you can see a densely packed coil in the segmental artery at the thoracic level. There are some other published data
with some coils in the segm the question is, which technique should we use, the first one, the second one? Another question, is which kind of coil to use? For the moment, we can only use the standard coils
in our center, but I think if we have 3-D or volume coils or if you have microvascular plugs that are very compatible with the microcatheter, we have a superior packing density, we can achieve a better occlusion of the segmental artery, and we have less procedure time and radiation time,
but we have to think of the cost. We recommend to start embolization of the segmental artery, of course, at the origin of it, and not too far inside. Here, you can see a patient where we have coiled a segmental artery very shortly after the ostium,
but you can see here also the development of the collaterals just shortly before the coils, leading to the perfusion of segmental artery that was above it. As you can see, we still have a lot of open question. Is it every patent segmental artery
a necessary to coil? Should we coil only the large ones? I show you an example here, you can see this segmental artery with a high-grade stenotic twisted ostium due to aortic enlargement.
I can show you this segmental artery, six weeks after coiling of a segmental artery lower, and you can see that the ostium, it's no more stenotic and you can see also the connection between the segmental artery below to the initial segmental artery.
Another question that we have, at which level should we start the MISACE? Here, can see a patient with a post-dissection aneurysm after pedicle technique, so these are all uncovered dissection stent, and you can see very nicely the anterior spinal artery
feeded by the anterior radiculomedullary artery from the segmental artery. So, in this patient, in fact, we start the coiling exactly at the seat of this level, we start to coil the segmental artery that feeds the anterior spinal artery.
So, normally we find this artery of the Th 9 L1, and you can see here we go upwards and downwards. We have some challenges with aneurysm sac enlargement, in this case, we use this technique to open the angle of the catheter, we can use also deflectable steerable sheath
in order to reach the segmental artery. And you can see here our results, again, I just will go fast through those, we have treated 57 patients, most of them were Type II, Type III aortic aneurysms. We have found in median nine patent segmental artery
at the level of the aorta to be treated, between 2 and 26, and we have coiled in multiple sessions with a mean interval of 60 days between the sessions. No sooner than seven days we perform the complete exclusion of the aneurysm
in order to let the collateral to develop, and you can see our result: at 30 days we had no spinal cord ischemia. So I can conclude that our first experience suggest that MISACE is feasible, safe, and effective, but segmental artery coiling in thoracoabdominal aneurysm
can be challenging, it's a new field with many open questions, and I looking forward for the results with PAPA_ARTiS study. Thank you a lot.
- So thank you to the organizers and to Dr. Veith, and thank you to Dr. Ouriel for giving me the introduction of the expense of an unsuitable procedure for pain patients. We have no disclosures.
I think when you look at MRV or Venous interventions, you can look at it as providing you a primary diagnosis, confirming a diagnosis if there's confusion. Procedural planning, you can use it as a procedural adjunct,
or you can use it as a primary procedural modality. In general, flow-dependent MRI has a low sensitivity and a slow acquisition time, making it practically impractical. Flow-independent MRI has become more popular, with sensitivity and specificities
rounding at 95 to 100%. There's a great deal of data on contrast-enhanced MRI, avoiding adanalenum using the iron compounds, and you'll hear later from Dr. Black about Direct Thrombus Imaging. There has been significant work on Thrombus Imaging,
but I will leave it up to him to talk about it. MR you can diagnose a DVT, either in both modalities, and you can see here with the arrows. It will also provide you data on the least inaccessible areas for duplex and other modalities,
such as the iliac veins and the IVC, as can be seen here. It is also perhaps easier to use than CTV, because at least in my institution CTV always comes out as a CTA, and I can't help that no matter what happens.
MR can also show you collaterals, which may be very important as you are trying to diagnose a patient. And in essence it may show you the smaller vein that you're more interested in, particularly in pelvic congestion syndrome,
such as this patient with an occluded internal iliac vein. It can also demonstrate, for those of you who deal with dialysis access, or it's central line problems, central venous stenosis and Thrombus. But equally importantly
it may show you that a stenosis is not intrinsic to the wall, but it's actually intrinsic to extravascular inflammation, as in this patient with mediastinal fibrosis, and which will give you a different way of what you wish to do and treat.
The European guidelines have addressed MR in it's future with chronic venous disease and they give it a 1C rating, and they recommend that if doesn't work you should proceed to Ibes. It can be used for the diagnoses of pulmonary embolism,
it can eliminate the use of ECHO, one can diagnose both the presence of the Thrombus, the dilatation of the ventricul, and if one is using Dynamic MR Imaging one can also see mcconnell sign or the equivalent on the septum between the two ventricles.
More interestingly it can also be used now in the chronic thrombuc, pulmonary hypertension, where it can show both the legions that are treatable and untreatable, as some of you may have heard from Dr. Roosevelt
earlier in the day, where they're now treating the outlying lesions with balloon angioplasty serial sessions. It can also look at the ventricul and give you some idea of where the ventricul stands with regard to it's performance,
we're looking at and linking this to the lungs. It can also show you the unusual, such as atresia of the IVC or it can help with you the diagnosis of Pelvic Congestion Syndrome. And it is extremely valuable
in dealing with AVM's, although it may take one, two, or three sessions with differing contrast bulosus to identify both the arterial, the intrinsic lesion, and the outflow lesions,
but a very valuable adjunct. In renal carcinoma it has two values, one is that it can may diagnosis venous invasion, and it may also let you understand whether or not you are dealing with bland thrombus or tumor thrombus,
which can change the staging for the patient and also change the actual intervention that you may perform. If you use flash imaging one will get at least an 89% sensitivity of the nature of thrombus,
whether it's bland or tumor thrombus, which may change what you need to do during the procedure. It could also tell you whether there's actual true wall invasion, which will require excision of the IVC
as opposed to the simple thromboendarterectomy. And this can run up to a specificity of 88% to exclude it. In the brain it's commonly used to diagnose the intra tumor vasculature. Diagnosing between veins and arterial systems, which can be helpful
particularly if one is considering percutaneous or other interventions. With regard to central venous stenosis there is some data and most people are now using an onlay technique where they take the MRI,
they develop the lines for the vessels and then use that as guide in one or two dimensions with fusion imaging to achieve access with a wire, catheter and balloon, as opposed to a blind stick technique.
There is data to show that you can image with the correct catheter balloons within the vessels and do serial MR's to show that it works. And finally with guidance catheters EP is now able to guide the catheter further and further in to achieve from the,
either the jugular or the venous access across the septum and to burn the entrium as appropriate. And finally, one can use MR to actually gain access, burn, and then actually use the MR to look at the specific tissue,
to show that you've achieved a burn at the appropriate area within the cardiac system and thus prove that your modality has achieved it. So in summary, we can use it for primary diagnosis, confirmatory diagnosis,
procedural planning, and procedural adjunct, but we're only still learning how to use it as a primary procedural modality. Thank you so much.
- Good morning. I'd like to thank Dr. Veith and Symposium for my opportunity to speak. I have no disclosures. So the in Endovascular Surgery, there is decrease open surgical bypass. But, bypass is still required for many patients with PAD.
Autologous vein is preferred for increase patency lower infection rate. And, Traditional Open Vein Harvest does require lengthy incisions. In 1996 cardiac surgery reported Endoscopic Vein Harvest. So the early prospective randomized trial
in the cardiac literature, did report wound complications from Open Vein Harvest to be as high as 19-20%, and decreased down to 4% with Endoscopic Vein Harvest. Lopes et al, initially, reported increase risk of 12-18 month graft failure and increased three year mortality.
But, there were many small studies that show no effect on patency and decreased wound complications. So, in 2005, Endoscopic Vein Harvest was recommended as standard of care in cardiac surgical patients. So what about our field? The advantages of Open Vein Harvest,
we all know how to do it. There's no learning curve. It's performed under direct visualization. Side branches are ligated with suture and divided sharply. Long term patency of the bypass is established. Disadvantages of the Open Vein Harvest,
large wound or many skip wounds has an increased morbidity. PAD patients have an increased risk for wound complications compared to the cardiac patients as high as 22-44%. The poor healing can be due to ischemia, diabetes, renal failure, and other comorbid conditions.
These can include hematoma, dehiscense, infection, and increased length of stay. So the advantages of Endoscopic Vein Harvest, is that there's no long incisions, they can be performed via one or two small incisions. Limiting the size of an incision
decreases wound complications. It's the standard of care in cardiac surgery, and there's an overall lower morbidity. The disadvantages of is that there's a learning curve. Electro-cautery is used to divide the branches, you need longer vein compared to cardiac surgery.
There's concern about inferior primary patency, and there are variable wound complications reported. So recent PAD data, there, in 2014, a review of the Society of Vascular Surgery registry, of 5000 patients, showed that continuous Open Vein Harvest
was performed 49% of the time and a Endo Vein Harvest about 13% of the time. The primary patency was 70%, for Continuous versus just under 59% for Endoscopic, and that was significant. Endoscopic Vein Harvest was found to be an independent risk factor for a lower one year
primary patency, in the study. And, the length of stay due to wounds was not significantly different. So, systematic review of Endoscopic Vein Harvest data in the lower extremity bypass from '96 to 2013 did show that this technique may reduce
primary patency with no change in wound complications. Reasons for decreased primary patency, inexperienced operator, increased electrocautery injury to the vein. Increase in vein manipulation, you can't do the no touch technique,
like you could do with an Open Harvest. You need a longer conduit. So, I do believe there's a roll for this, in the vascular surgeon's armamentarium. I would recommend, how I use it in my practices is, I'm fairly inexperienced with Endoscopic Vein Harvest,
so I do work with the cardiac PA's. With increased percutaneous procedures, my practice has seen decreased Saphenous Vein Bypasses, so, I've less volume to master the technique. If the PA is not available, or the conduit is small, I recommend an Open Vein Harvest.
The PA can decrease the labor required during these cases. So, it's sometimes nice to have help with these long cases. Close surveillance follow up with Non-Invasive Arterial Imaging is mandatory every three months for the first year at least. Thank you.
- This talk is a brief one about what I think is an entity that we need to be aware of because we see some. They're not AVMs obviously, they're acquired, but it nevertheless represents an entity which we've seen. We know the transvenous treatment of AVMs is a major advance in safety and efficacy.
And we know that the venous approach is indeed very, very favorable. This talk relates to some lesions, which we are successful in treating as a venous approach, but ultimately proved to be,
as I will show you in considerable experience now, I think that venous thrombosis and venous inflammatory disease result in acquired arteriovenous connections, we call them AVMs, but they're not. This patient, for example,
presented with extensive lower extremity swelling after an episode of DVT. And you can see the shunting there in the left lower extremity. Here we go in a later arterial phase. This lesion we found,
as others, is best treated. By the way, that was his original episode of DVT with occlusion. Was treated with stenting and restoration of flow and the elimination of the AVM.
So, compression of the lesion in the venous wall, which is actually interesting because in the type perivenous predominant lesions, those are actually lesions in the vein wall. So these in a form, or in a way, assimilate the AVMs that occur in the venous wall.
Another man, a 53-year-old gentleman with leg swelling after an episode of DVT, we can see the extensive filling via these collaterals, and these are inflammatory collaterals in the vein wall. This is another man with a prior episode of DVT. See his extensive anterior pelvic collaterals,
and he was treated with stenting and success. A recent case, that Dr. Resnick and I had, I was called with a gentleman said he had an AVM. And we can see that the arteriogram sent to me showed arterial venous shunting.
Well, what was interesting here was that the history had not been obtained of a prior total knee replacement. And he gave a very clear an unequivocal history of a DVT of sudden onset. And you can see the collaterals there
in the adjacent femoral popliteal vein. And there it is filling. So treatment here was venous stenting of the lesion and of the underlying stenosis. We tried an episode of angioplasty,
but ultimately successful. Swelling went down and so what you have is really a post-inflammatory DVT. Our other vast experience, I would say, are the so-called uterine AVMs. These are referred to as AVMs,
but these are clearly understood to be acquired, related to placental persistence and the connections between artery and veins in the uterus, which occurs, a part of normal pregnancy. These are best treated either with arterial embolization, which has been less successful,
but in some cases, with venous injection in venous thrombosis with coils or alcohol. There's a subset I believe of some of our pelvic AVMs, that have histories of DVT. I believe they're silent. I think the consistency of this lesion
that I'm showing you here, that if we all know, can be treated by coil embolization indicates to me that at least some, especially in patients in advanced stage are related to DVT. This is a 56-year-old, who had a known history of prostate cancer
and post-operative DVT and a very classic looking AVM, which we then treated with coil embolization. And we're able to cure, but no question in my mind at least based on the history and on the age, that this was post-phlebitic.
And I think some of these, and I think Wayne would agree with me, some of these are probably silent internal iliac venous thromboses, which we know can occur, which we know can produce pulmonary embolism.
And that's the curative final arteriogram. Other lesions such as this, I believe are related, at least some, although we don't have an antecedent history to the development of DVT, and again of course,
treated by the venous approach with cure. And then finally, some of the more problematic ones, another 56-year-old man with a history of prior iliofemoral DVT. Suddenly was fine, had been treated with heparin and anticoagulation.
And suddenly appeared with rapid onset of right lower extremity swelling and pain. So you see here that on an arteriogram of the right femoral, as well as, the super selective catheterization of some of these collaterals.
We can see the lesion itself. I think it's a nice demonstration of lesion. Under any other circumstance, this is an AVM. It is an AVM, but we know it to be acquired because he had no such swelling. This was treated in the only way I knew how to treat
with stenting of the vein. We placed a stent. That's a ballon expanded in the angiogram on your right is after with ballon inflation. And you can see the effect that the stenting pressure, and therefore subsequently occlusion of the compression,
and occlusion of the collaterals, and connections in the vein wall. He subsequently became asymptomatic. We had unfortunately had to stent extensively in the common femoral vein but he had an excellent result.
So I think pelvic AVMs are very similar in location and appearance. We've had 13 cases. Some with a positive history of DVT. I believe many are acquired post-DVT, and the treatment is the same venous coiling and or stent.
Wayne has seen some that are remarkable. Remember Wayne we saw at your place? A guy was in massive heart failure and clearly a DVT-related. So these are some of the cases we've seen
and I think it's noteworthy to keep in mind, that we still don't know everything there is to know about AVMs. Some AVMs are acquired, for example, pelvic post-DVT, and of course all uterine AVMs. Thanks very much.
(audience applause) - [Narrator] That's a very interesting hypothesis with a pelvic AVMs which are consistently looking similar. - [Robert] In the same place right? - [Narrator] All of them are appearing at an older age. - [Robert] Yep.
Yep. - This would be a very, very good explanation for that. I've never thought about that. - Yeah I think-- - I think this is very interesting. - [Robert] And remember, exactly.
And I remember that internal iliac DVT is always a silent process, and that you have this consistency, that I find very striking. - [Woman] So what do you think the mechanism is? The hypervascularity looked like it was primarily
arterial fluffy vessels. - [Robert] No, no, no it's in the vein wall. If you look closely, the arteriovenous connections and the hypervascularity, it's in the vein wall. The lesion is the vein wall,
it's the inflammatory vein. You remember Tony, that the thing that I always think of is how we used to do plain old ballon angioplasty in the SFA. And afterwards we'd get this
florid venous filling sometimes, not every case. And that's the very tight anatomic connection between those two. That's what I think is happening. Wayne? - [Wayne] This amount is almost always been here.
We just haven't recognized it. What has been recognized is dural fistula-- - Yep. - That we know and that's been documented. Chuck Kerber, wrote the first paper in '73 about the microvascular circulation
in the dural surface of the dural fistula, and it's related to venous thrombosis and mastoiditis and trauma. And then as the healing process occurs, you have neovascular stimulation and fistulization in that dural reflection,
which is a vein wall. And the same process happens here with a DVT with the healing, the recanalization, inflammation, neovascular stimulation, and the development of fistulas. increased vascular flow into the lumen
of the thrombosed area. So it's a neovascular stimulation phenomenon, that results in the vein wall developing fistula very identical to what happens in the head with dural fistula had nothing described of in the periphery.
- [Narrator] Okay, very interesting hypothesis.
Thanks very much, Tom. I'll be talking about thermal ablation on anticoagula is it safe and effective? I have no disclosures. As we know, extensive review of both RF and laser
ablation procedures have demonstrated excellent treatment effectiveness and durability in each modality, but there is less data regarding treatment effectiveness and durability for those procedures in patients who are also on systemic anticoagulation. As we know, there's multiple studies have been done
over the past 10 years, with which we're all most familiar showing a percent of the durable ablation, both modalities from 87% to 95% at two to five years. There's less data on those on the anticoagulation undergoing thermal ablation.
The largest study with any long-term follow up was by Sharifi in 2011, and that was 88 patients and follow-up at one year. Both RF and the EVLA had 100% durable ablation with minimal bleeding complications. The other studies were all smaller groups
or for very much shorter follow-up. In 2017, a very large study came out, looking at the EVLA and RF using 375 subjects undergoing with anticoagulation. But it was only a 30-day follow-up, but it did show a 30% durable ablation
at that short time interval. Our objective was to evaluate efficacy, durability, and safety of RF and EVLA, the GSV and the SSV to treat symptomatic reflux in patients on therapeutic anticoagulation, and this group is with warfarin.
The data was collected from NYU, single-center. Patients who had undergone RF or laser ablation between 2011 and 2013. Ninety-two vessels of patients on warfarin at the time of endothermal ablation were selected for study. That's the largest to date with some long-term follow-up.
And this group was compared to a matched group of 124 control patients. Devices used were the ClosureFast catheter and the NeverTouch kits by Angiodynamics. Technical details, standard IFU for the catheters. Tumescent anesthetic.
And fiber tips were kept about 2.5 centimeters from the SFJ or the SPJ. Vein occlusion was defined as the absence of blood flow by duplex scan along the length of the treated vein. You're all familiar with the devices, so the methods included follow-up, duplex ultrasound
at one week post-procedure, and then six months, and then also at a year. And then annually. Outcomes were analyzed with Kaplan-Meier plots and log rank tests. The results of the anticoagulation patients, 92,
control, 124, the mean follow-up was 470 days. And you can see that the demographics were rather similar between the two groups. There was some more coronary disease and hypertension in the anticoagulated groups, and that's really not much of a surprise
and some more male patients. Vessels treated, primarily GSV. A smaller amount of SSV in both the anticoagulated and the control groups. Indications for anticoagulation.
About half of the patients were in atrial fibrillation. Another 30% had a remote DVT in the contralateral limb. About 8% had mechanical valves, and 11% were for other reasons. And the results. The persistent vein ablation at 12 months,
the anticoagulation patients was 97%, and the controls was 99%. Persistent vein ablation by treated vessel, on anticoagulation. Didn't matter if it was GSV or SSV. Both had persistent ablation,
and by treatment modality, also did not matter whether it was laser or RF. Both equivalent. If there was antiplatelet therapy in addition to the anticoagulation, again if you added aspirin or Clopidogrel,
also no change. And that was at 12 months. We looked then at persistent vein ablation out at 18 months. It was still at 95% for the controls, and 91% for the anticoagulated patients. Still not statistically significantly different.
At 24 months, 89% in both groups. Although the numbers were smaller at 36 months, there was actually still no statistically significant difference. Interestingly, the anticoagulated group actually had a better persistent closure rate
than the control group. That may just be because the patients that come back at 36 months who didn't have anticoagulation may have been skewed. The ones we actually saw were ones that had a problem. It gets harder to have patients
come back at three months who haven't had an uneventful venous ablation procedure. Complication, no significant hematomas. Three patients had DVTs within 30 days. One anticoagulation patient had a popliteal DVT, and one control patient.
And one control patient had a calf vein DVT. Two EHITs. One GSV treated with laser on anticoagulation noted at six days, and one not on anticoagulation at seven days. Endovenous RF and EVLA can be safely performed
in patients undergoing long-term warfarin therapy. Our experience has demonstrated a similar short- and mid-term durability for RF ablation and laser, and platelet therapy does not appear to impact the closer rates,
which is consistent with the prior studies. And the frequency of vein recanalization following venous ablation procedures while on ACs is not worse compared to controls, and to the expected incidence as described in the literature.
This is the largest study to date with follow-up beyond 30 days with thermal ablation procedures on anticoagulation patients. We continue to look at these patients for even longer term durability. Thanks very much for your attention.
- Thank you very much, so my disclosures, I'm one of the co-PIs for national registry for ANARI. And clearly venous clot is different, requires different solutions for the arterial system. So this is a device that was built ground up to work in the venous system. And here's a case presentation of a 53 year old male,
with a history of spondylolisthesis had a lumbar inner body fusion, he had an anterior approach and corpectomy with application of an inner body cage. And you can see these devices here. And notably he had application of local bone graft and bone powder
and this is part of what happened to this patient. About seven days later he came in with significant left leg swelling and venous duplex showed clot right here, and this extended all the way down to the tibial vessels. And if you look at the CT
you can see extravasation of that bone powder and material obstructing the left iliac vein. And had severe leg swelling so the orthopedic people didn't want us to use TPA in this patient so we considered a mechanical solution. And so at this day and age I think goals of intervention
should be to maximize clot removal of course and minimize bleeding risk and reduce the treatment or infusion time and go to single session therapy whenever possible. Our ICUs are full all the time and so putting a lytic patient in there
reduces our ability to get other patients in. (mouse clicks So this is the ClotTriever thrombectomy device. It has a sheath that is a 13 French sheath and they're developing a 16 French, that opens up with a funnel
after it's inserted into the poplitiel. So the funnel is in the lower femoral vein and this helps funnel clot in when it's pulled down. The catheter has this coring element that abuts the vein wall and carves the thrombus off in a collecting bag
that extends up above to allow the thrombus to go into the bag as you pull it down. So you access the popliteal vein, cross the thrombosed segments with standard techniques and you need to then put an exchange length wire up into the SVC
or even out into the subclavian vein for stability. And then the catheter's inserted above the clot and is gradually pulled down, sort of milking that stuff off of the wall and into the bag that is then taken down to the funnel and out of the leg.
So this is the patient we had, we had thrombus in the femoral and up into the IVC. Extensive, you can see the hardware here. And it was very obstructed right at that segment where it was, had the bone material pushing on the vein it was quite difficult to get through there
but finally we did and we ballooned that to open a channel up large enough to accommodate ClotTriever catheter. We then did multiple passes and we extracted a large amount of thrombus. Some looking like typically acute stuff
and then some more dense material that may have been a few days worth of build up on the wall there. We then stinted with an 18 by 90 across the obstructed segment and this was our completion run.
It's not perfect but it looks like a pretty good channel going through. This is the hardware not obstruction at that level. Hospital course, the patient had significant improvement in their swelling by post-op day one. Was discharged on compression and anti-coagulation.
He returned about two months ago for his three month follow-up and really had very minimal symptoms in the left leg. Venous duplex showed that the left common femoral was partially compressible but did have phasic flow and the stent appeared to be open through it's course.
So of course this is an anecdote, this is early in the experience with this catheter. There have been numerous improvements made to ease the use of it and do it in fewer steps. And so we're starting a ClotTriever outcomes registry
to enroll up to 500 patients to begin to define outcomes with this device. It does offer the promise of single session therapy without lytic administration and we'll see how it performs and which patients it works best in through the registry.
Thank you very much.
So I think when it comes to distal bypasses and ultra-distal bypasses it's all about how we make our decision. We know now that early intervention these patients have better outcome. We use waveform analysis to make our decision about how critical their skin is
we use different topical anesthesia depending the patient's fitness. I think this is just one important point that patient's with dark skin did not show all the full range of skin changes and patients get this dark foot sign
even before they start necrosing their skin. It's very important how we give our anesthetics we use vascular anesthesia with special interest prevascular disease because these patients are quite labile. We use even sometimes inotropes during the procedure
and post operative to maintain a good blood pressure. We believe that short bypasses have got better outcomes. Dr. Veith, have already published in the 80s about short bypasses also doing now the Tibiotibial bypasses on the look anesthetic. Some patients with very high risk for general anesthesia.
And our study we showed that the majority of our patients, who had ultra-distal bypasses had the bypasses from either popliteal or SFA artery. We use different techniques to improve on how to take our bypasses from the proximal anastomosis distally. So we use hybrid revascularization, we use drug-eluting
balloons, and stenting of the SFA and popliteal artery, so we can perform our bypass from the popliteal level. We even use Remote Endarterectomy to improve on our length of the inflow. So by doing remote endarterectomy of the SFA
and popliteal artery, we can take the bypass quite distally from the popliteal artery to the foot level. This is a patient who got critical leg ischaemia on the right side limited, venous conduit. We did remote endarterectomy of her SFA and popliteal artery. And then we can
easily take the bypass from the popliteal artery down to the foot level. On the left side, she had hybrid revascularization with SFA stenting and ultra-distal bypass. We use venous conduit in almost all our patients with ultra-distal bypass.
In distal bypasses we can PTFE but the majority of our patients have long saphenous veins or even arm veins. We started using Omniflow in our infected patients for distal bypasses with quite good results. We scan all our veins prior to the procedure
to make sure that we got good quality vein and amount to perform the procedure. We have published in our small veins series less than 3mm, we still have a very good outcome in distal bypasses. Especially when we do tibial bypasses
or dorsalis pedis bypasses we turn the grafts anatomically. You can see in this angiogram the graft going through the interosseous membrane down to the foot level. We put our incision a bit immediately on the foot level so if there is necrosis of the wound on the foot level that we don't expose the graft, especially when we
knew the patient was coming from the lateral aspect through the interosseous membrane. We select our bypasses especially in the foot level using the duplic scanogram, angiogram or CT angiogram. During the procedure we don't clamp our arteries we use the Flo-Rester and Flo-Through prothesis
to stop patients from bleeding while we're doing it. And we've never used tourniquet before all this has been published. Hand held doppler is the only quality control that we do we don't do on-table angiograms and we find this quite useful for our patients.
We can do the debridement and at the same time while we're doing the bypass at the ankle level. As for anticoagulation and antiplatelet therapy We do antiplatelet therapy for all patient with distal and ultra-distal bypass. And we use heparin and warfarin for patients
who have got redo surgery. Graft surveillance for all our patients Unfortunately, we can only afford it in the NHS for one year, but if the patient get an intervention they go for another full year. Salvage angioplasty is essential for these patients
and we treat these patients as quite as a emergency when they present. So, conclusion, Mr. Sherman, ladies and gentlemen, distal and ultra-distal bypasses require good planning. We use veins for all our bypasses when it comes to the foot level and ultra-distal bypasses,
and of course selecting the target vessel in the foot is very important. Graft Surveillance is essential to maintain quality and outcome for these patients. Thank you very much.
- I just like the title 'cuz I think we're in chaos anyway. Chaos management theory. Alright, unfortunately I have nothing to disclose, it really upsets me. I wish I had a laundry list to give you. Gettin' checks from everybody, it would be great. Let's start off with this chaos, what has been published.
Again "Ul Haq et al" is a paper from Hopkins. Bleomycin foam treatment of malformations, a promising agent. And they had 20 patients, 21 Bleomycin procedures. (mumbles) sclerosants in a few other patients, 40% complication rate, 30% minor, 10% major.
On a per procedure basis it was a 29% with about 7% major. All patients had decrease in symptoms. But to say "I use Bleomycin" or "I use X" because a complication (mumbles) is nonsense, you're mentally masturbating. It ain't going to be that way, you're going to have complications.
Alright, the use of Bleomycin should be reserved for locations where post-procedure swelling would be dangerous. Well they used it, and one patient required intubation for four days and another patient 15 days. So, it can happen with any agent.
So I don't know why that statement was made. "Hassan et al", noninvasive management of hemangiomas and vascular malformations using Bleomycin again, this handles the plastic surgery a few years ago. 71% effectiveness rate, 29% failure rate,
14% complication rate, 5 major ulcerations. Ulcerations happen with any agent. You're not going to escape that by saying, "Oh, well I'm not going to use alcohol because (mumbles)." No you're going to get it anyway. You all in the literature.
"Sainsbury", intra-lesional Bleomycin injection for vascular birthmarks five year experience again, 2011. 82% effectiveness, 17.3 for failure. Compli- severe blistering, ulcers, swelling, infections, recurrences. Okay, everybody's reporting it.
"Bai et al" sclerotherapy for lymphatic, oral and facial region, 2009. 43% effectiveness, but they found if they used it with surgery they had a higher effectiveness rate. Good. But again that's their effectiveness.
"Young et al", Bleomycin A5 cervico-facial vascular surgery, 2011. 81% effectiveness rate 19% failure for macrocystic. 37% failure from microcystic disease. Complications: ulcerations, hematoma, bleeding, fevers, soft tissue atrophy.
"Zhang et al." Now this is a study. They're goin' head-to-head alcohol versus Bleo. Oh, isn't that a nice thing to do. Huh, funny how that can happen sometimes. There's another paper out of Canada
that doesn't matter, there's 17 pages and there's no statistical significance for that. 138 patients, you got a lot of statistics. "Zhang et al", 138 children. 71 of 75 patients, which is 95% of that serie, were either cured,
markedly effective, or effective, with alcohol. In the Bleo group 41 of 63, that is 65% of the patients, had effective treatment. That means no cures, no markedly effective, just effective. That's their head-to-head comparison. Difference between Ethanol and
the Bleo group again was statistically significant. Ethanol at 75 patients of 14 cases skin necrosis. Bleo group at 63 patients of 5 cases skin necrosis. And in that group they stated it is statistically superior to Bleo. 95 versus 60, that's a big deal.
Again, cured, disappearance post-treatment without recurrence. Markedly effective, meant that greater than 80% was ablated. Effective means about less that 80% reduction but improved. Ineffective, no change. That was their criterion on that paper.
Again, 30 cases, superficial VMs effective rate was 95% in the Ethanol group and the deep group 94%. Okay. What was in the Bleo group? 68% superficial, 56% of deep group. So that's a statistical significance
of failure, between the two agents, comparing head-to-head in anatomic areas. Ethanol VM papers, let's go on to that, we're goin' to do other stuff. "Lee et al", advanced management, 2003, midterm results. 399 procedures in 87 patients,
95% significant or complete ablation, 12.4% complication. "Johnson et al", Kansas. University of Kansas med center, 2002. 100% success rate in tongues. One patient had a massive tongue and had breathing difficulties prior to treatment
remained intubated 5 days and then uneventfully discharged, that was their only complication. "Su et al", ethanol sclerotherapy, face and neck. Again, these are complex anatomies with complex issues of cranial nerves as well as airway control. 2010, 56 of 60 procedures, 90%, four minimal residual,
no skin necrosis, no nerve injuries. "Orlando", outpatient percutaneous treatment, low doses under local anesthesia. This is a very interesting paper out of Brazil. They did 'em under IV sedation, just a little bit by little bit.
They said they had trouble gettin' general so they had to figure another way. Smart, I like people thinkin' things out. Who here doesn't have a problem with anesthesia? Gettin' 'em not to quit before two o'clock? (laughs)
Alright, used local only 39 patients extremity VMs, main symptoms of pain. Cure or significant improvement in 94%. One ulcer, 3 transient paresthesias. "Lee et al", sclerotherapy craniofacial again, 2009. 87 patients, 75% were reductions.
71 of 87 excellent outcomes. One patient transient, tongue decreased sensation. One transient facial nerve palsy, no skin injuries. "Vogelzang" is a very important paper of a single center. Is that author- anybody here? Again, they did VMs and AVMs in this series
and then a per patient complication rate is 13.3, in AMVs 9.7 per patient, but I think what also is important is to do things with regards to procedures. And they listed both. So we'll just, it's about time to quit. This is our embolization series.
And neck, upper extremity, all the anatomies. And we're about a 10 to three ratio with regards to VM/LMs to AVMs in numbers. I think everybody's pretty much like that, a third of their practice. Again, our minor complications are that.
Major complications are these. Summary, what we found in the literature is that Ethanol publications state its efficacy rate routinely at 90 to 100%. And all other second tier sclerosants are 60 to 80%. So I think that's the take home message.
- Thank you, Dr. Ascher. Great to be part of this session this morning. These are my disclosures. The risk factors for chronic ischemia of the hand are similar to those for chronic ischemia of the lower extremity with the added risk factors of vasculitides, scleroderma,
other connective tissue disorders, Buerger's disease, and prior trauma. Also, hemodialysis access accounts for a exacerbating factor in approximately 80% of patients that we treat in our center with chronic hand ischemia. On the right is a algorithm from a recent meta-analysis
from the plastic surgery literature, and what's interesting to note is that, although sympathectomy, open surgical bypass, and venous arterialization were all recommended for patients who were refractory to best medical therapy, endovascular therapy is conspicuously absent
from this algorithm, so I just want to take you through this morning and submit that endovascular therapy does have a role in these patients with digit loss, intractable pain or delayed healing after digit resection. Physical examination is similar to that of lower extremity, with the added brachial finger pressures,
and then of course MRA and CTA can be particularly helpful. The goal of endovascular therapy is similar with the angiosome concept to establish in-line flow to the superficial and deep palmar arches. You can use an existing hemodialysis access to gain access transvenously to get into the artery for therapy,
or an antegrade brachial, distal brachial puncture, enabling you treat all three vessels. Additionally, you can use a retrograde radial approach, which allows you to treat both the radial artery, which is typically the main player in these patients, or go up the radial and then back over
and down the ulnar artery. These patients have to be very well heparinized. You're also giving antispasmodic agents with calcium channel blockers and nitroglycerin. A four French sheath is preferable. You're using typically 014, occasionally 018 wires
with balloon diameters 2.3 to three millimeters most common and long balloon lengths as these patients harbor long and tandem stenoses. Here's an example of a patient with intractable hand pain. Initial angiogram both radial and ulnar artery occlusions. We've gone down and wired the radial artery,
performed a long segment angioplasty, done the same to the ulnar artery, and then in doing so reestablished in-line flow with relief of this patient's hand pain. Here's a patient with a non-healing index finger ulcer that's already had
the distal phalanx resected and is going to lose the rest of the finger, so we've gone in via a brachial approach here and with long segment angioplasty to the radial ulnar arteries, we've obtained this flow to the hand
and preserved the digit. Another patient, a diabetic, middle finger ulcer. I think you're getting the theme here. Wiring the vessels distally, long segment radial and ulnar artery angioplasty, and reestablishing an in-line flow to the hand.
Just by way of an extreme example, here's a patient with a vascular malformation with a chronically occluded radial artery at its origin, but a distal, just proximal to the palmar arch distal radial artery reconstitution, so that served as a target for us to come in
as we could not engage the proximal radial artery, so in this patient we're able to come in from a retrograde direction and use the dedicated reentry device to gain reentry and reestablish in-line flow to this patient with intractable hand pain and digit ulcer from the loss of in-line flow to the hand.
And this patient now, two years out, remains patent. Our outcomes at the University of Pennsylvania, typically these have been steal symptoms and/or ulceration and high rates of technical success. Clinical success, 70% with long rates of primary patency comparing very favorably
to the relatively sparse literature in this area. In summary, endovascular therapy can achieve high rates of technical, more importantly, clinical success with low rates of major complications, durable primary patency, and wound healing achieved in the majority of these patients.
- So, I'm going to probably echo many of the themes that Gary just touched upon here. These are my disclosures. So, if we look at the CHEST guidelines on who should get pharmacomechanical techniques, it is very very very sobering, and I apologize if the previous speakers have shown this slide,
but essentially, what's right now being disseminated to the American College of CHEST Physicians is that nobody should get catheter-directed thrombolysis, the concept of pharmacomechanical technique should really only reserved as a last-ditch effort if nothing else works, if you happen to have somebody
with extraordinary expertise in your institution, it could not be more of a damning recommendation for what I'm about to talk to you about for the next eight or nine minutes or so. So, then the question is, what is the rationale? What are we talking about here?
And again, I'm going to say that Gary and I, I think are sort of kindred spirits in recognizing that we really do need to mature this concept of the catheter-based technique for pulmonary embolism. So, I'm going to put out a hypothetical question, what if there was a single session/single device therapy
for acute PE, Gary showed one, that could avoid high dose lytics, avoid an overnight infusion, acutely on the table lower the PA pressure, acutely improve the function of the right ventricle, rapidly remove, you know, by angiography,
thrombus and clot from the pulmonary artery, and it was extremely safe, what if we had that? Would that change practice? And I would respectfully say, yes it would. And then what if this concept has already been realized, and we're actually using this across the world
for STEMI, for stroke, for acute DVT, and so why not acute pulmonary embolism? What is limiting our ability to perform single session, rapid thrombus removal and
patient stabilization on the table? Gary showed this slide, there's this whole litany of different devices, and I would argue none of them is exactly perfect yet, but I'm going to try and sort of walk you through what has been developed in an attempt
to reach the concept of single session therapy. When we talk about pharmacomechanical thrombectomy or thrombo-aspiration, it really is just one line item on the menu of all the different things that we can offer patients that present with acutely symptomatic PE, but it is important to recognize
what the potential benefits of this technology are and, of course, what the limitations are. When we look at this in distinction to stroke or STEMI or certainly DVT, it's important to recognize that during a surgical pulmonary embolectomy case, the clot that's able to be extracted is quite impressive,
and this is a very very very sobering amount of material that is typically removed from the patient's right heart and their pulmonary circulation, so, in order to innovate and iterate a percutaneous technology based on existing concepts,
it really does demand significant disruption to achieve the goals, we have not tackled this yet in terms of our endovascular tool kit. So, what is the role? Well, it's potentially able to debulk in acute PE, in an intermediate risk patient which would
ideally eliminate the need for overnight lysis, as Gary alluded to, but what if it could actually replace surgical embolectomy in high risk patients? I think many of us have had the conversation where we, we sort of don't know that's there a
experienced, comfortable surgeon to do an embolectomy within the building or within immediate access to the patient that we see crashing in front of our eyes. I'm very very lucky here in New York that I've incredible cardiovascular surgeons that are able to perform this procedure very very safely 24/7,
but I know that's not the case across the country. So, one of our surgeons who actually came from the Brigham and Women's Hospital in Boston developed this concept, which was the sort of first bridge between surgical embolectomy and percutaneous therapy, which is a large bore aspiration catheter,
it's a 22 French cannula that was originally designed to be placed through a cutdown but can now be placed percutaneously, and I think many of us in the room are familiar with this technology, but essentially you advance this under fluoroscopy into the right heart,
place the patient on venous-venous bypass, and a trap, which is outside the patient, is demonstrated in the lower left portion of the screen here, is able to capture any thrombotic material and then restore the circulation via the contralateral femoral vein,
any blood that is aspirated. Very very scant data on this, here's the experience from Michael and Kenny up in Boston where they tried this technology in just a handful of cases, this was followed by John Moriarty's experience from UCLA, where he actually argued a little bit of caution
using this technology, largely related to its inability to safely and reliably deliver it to the pulmonary circulation. To that end, AngieDynamics is funding a prospective registry really looking at safety and efficacy at delivering this device to the pulmonary circulation
and its ability to treat acute pulmonary embolism as well as any right heart clot, but that data's not commercially available yet. This is just one case that we did recently of a clot in transit, which I would argue could not be treated with any other technology
and the patient was able to be discharged the same day, I personally think this is a wonderful application of this technology and is our default strategy right now for a very large clot in transit. The second entrance to the space is the Inari FlowTriever device, which is a 20 French cannula,
it does not require a perfusion team in vein-vein bypass, the concept is simple, a 20 French guide catheter is advanced into the pulmonary circulation and these trilobed disks, which function like a stentriever for stroke are deployed in the pulmonary circulation, retracted to allow the clot to be delivered to the guide cath,
and then using manual aspiration, the clot is retrieved from the patient. Just a few case reports in small series describing this, this one in JACC two years ago, showing quite robust ability to extract a clot, this company which is a relatively small company funded a
single-arm prospective trial enrolling 168 patients, and not only did they complete enrollment last year, but they actually received FDA approval, now there is no peer-reviewed literature on this, it has undergone public presentation, but we, we really don't know exactly which patients were treated,
and so we really can't dissect this, I think there is a learning curve to this technology, and it's not, certainly, ready for broad dissemination yet, we just don't know which patients are ideal for it currently. Another technology, the Penumbra CAT8 system,
a market reduction in the size, an 8 French catheter based technology, this is exact same technology that's used for thrombo-aspiration for acute ischemic stroke, currently just in a slightly different size, and then a number of cases demonstrating its efficacy at
alleviating the acute nonperfusion of an entire lobe, as Gary was referring to previously, and this is one of our cases from our own lab, where you see there's no perfusion of the right, middle and lower lobe, I'm not sure if I can get these movies to play here, oh here it goes,
and so using sort of a handmade separator, we were able to restore perfusion again to the right, middle and lower lobe here, so just one example where, I think there is a potential benefit of thrombo-aspiration in a completely occluded segment.
There has been a wealth of literature about this technology, mostly demonstrating safety and efficacy, the most recent one on the bottom right in CVIR demonstrates the ability to acutely reduce the PA pressures on the table with the use of this technology, and to that end,
Akhi Sista, our faculty here this morning, is the national principal investigator of a US multicenter prospective study looking at exactly that, to try and prove that this technology is safe and effective in the treatment of submassive pulmonary embolism, so more to come on that.
Lastly, the AngioJet System, probably the most reported and studied technology, this is a 6 French technology by default, a wealth of literature here showing safety and efficacy, however, due to adverse event reporting, this technology currently has black box label warnings
in the treatment of acute pulmonary embolism, so clearly this technology should not be used by the novice, and there are significant safety concerns largely related to bradyarrhythmias and hypotension, that being said, again, it is a quite experienced technology for this. So where do we currently stand?
I think we clearly see there are several attributes for thrombo-aspiration including just suction aspiration, a mechanical stent-triever technology, and the ability to not just insanguinate the patient but actually restore circulation and not make the patient anemic, here,
you can see where these technologies are going in terms of very very large bore and very small bore, I placed the question marked right in the center which is where I think this technology needs to converge in order to lead to the disruption for the broad adoption of a single session technology.
So, numerous devices exist, all the devices have been used clinically and have demonstrated the ability to be delivered in aspirary pulmonary embolus, at present, unfortunately there is no consensus regarding which device should be used for which patients and in which clinical presentations,
we need many prospective studies to demonstrate the safety and clinical benefit for our patients, we desperately do need a single session therapy, again, I completely agree with Gary on this, but there is a lot of work yet to do. Thank you for your attention.
- Good morning. It's a pleasure to be here today. I'd really like to thank Dr. Veith, once again, for this opportunity. It's always an honor to be here. I have no disclosures. Heel ulceration is certainly challenging,
particularly when the patients have peripheral vascular disease. These patients suffer from significant morbidity and mortality and its real economic burden to society. The peripheral vascular disease patients
have fivefold and increased risk of ulceration, and diabetics in particular have neuropathy and microvascular disease, which sets them up as well for failure. There are many difficulties, particularly poor patient compliance
with offloading, malnutrition, and limitations of the bony coverage of that location. Here you can see the heel anatomy. The heel, in and of itself, while standing or with ambulation,
has tightly packed adipose compartments that provide shock absorption during gait initiation. There is some limitation to the blood supply since the lateral aspect of the heel is supplied by the perforating branches
of the peroneal artery, and the heel pad is supplied by the posterior tibial artery branches. The heel is intolerant of ischemia, particularly posteriorly. They lack subcutaneous tissue.
It's an end-arterial plexus, and they succumb to pressure, friction, and shear forces. Dorsal aspect of the posterior heel, you can see here, lacks abundant fat compartments. It's poorly vascularized,
and the skin is tightly bound to underlying deep fascia. When we see these patients, we need to asses whether or not the depth extends to bone. Doing the probe to bone test
using X-ray, CT, or MRI can be very helpful. If we see an abcess, it needs to be drained. Debride necrotic tissue. Use of broad spectrum antibiotics until you have an appropriate culture
and can narrow the spectrum is the way to go. Assess the degree of vascular disease with noninvasive testing, and once you know that you need to intervene, you can move forward with angiography. Revascularization is really operator dependent.
You can choose an endovascular or open route. The bottom line is the goal is inline flow to the foot. We prefer direct revascularization to the respective angiosome if possible, rather than indirect. Calcanectomy can be utilized,
and you can actually go by angiosome boundaries to determine your incisions. The surgical incision can include excision of the ulcer, a posterior or posteromedial approach, a hockey stick, or even a plantar based incision. This is an example of a posterior heel ulcer
that I recently managed with ulcer excision, flap development, partial calcanectomy, and use of bi-layered wound matrix, as well as wound VAC. After three weeks, then this patient underwent skin grafting,
and is in the route to heal. The challenge also is offloading these patients, whether you use a total contact cast or a knee roller or some other modality, even a wheelchair. A lot of times it's hard to get them to be compliant.
Optimizing nutrition is also critical, and use of adjunctive hyperbaric oxygen therapy has been shown to be effective in some cases. Bone and tendon coverage can be performed with bi-layered wound matrix. Use of other skin grafting,
bi-layered living cell therapy, or other adjuncts such as allograft amniotic membrane have been utilized and are very effective. There's some other modalities listed here that I won't go into. This is a case of an 81 year old
with osteomyelitis, peripheral vascular disease, and diabetes mellitus. You can see that the patient has multi-level occlusive disease, and the patient's toe brachial index is less than .1. Fortunately, I was able to revascularize this patient,
although an indirect revascularization route. His TBI improved to .61. He underwent a partial calcanectomy, application of a wound VAC. We applied bi-layer wound matrix, and then he had a skin graft,
and even when part of the skin graft sloughed, he underwent bi-layer living cell therapy, which helped heal this wound. He did very well. This is a 69 year old with renal failure, high risk patient, diabetes, neuropathy,
peripheral vascular disease. He was optimized medically, yet still failed to heal. He then underwent revascularization. It got infected. He required operative treatment,
partial calcanectomy, and partial closure. Over a number of months, he did finally heal. Resection of the Achilles tendon had also been required. Here you can see he's healed finally. Overall, function and mobility can be maintained,
and these patients can ambulate without much difficulty. In conclusion, managing this, ischemic ulcers are challenging. I've mentioned that there's marginal blood supply, difficulties with offloading, malnutrition, neuropathy, and arterial insufficiency.
I would advocate that partial or total calcanectomy is an option, with or without Achilles tendon resection, in the presence of osteomyelitis, and one needs to consider revascularization early on and consider a distal target, preferentially in the angiosome distribution
of the posterior tibial or peroneal vessels. Healing and walking can be maintained with resection of the Achilles tendon and partial resection of the os calcis. Thank you so much. (audience applauding)
- So I'm just going to talk a little bit about what's new in our practice with regard to first rib resection. In particular, we've instituted the use of a 30 degree laparoscopic camera at times to better visualize the structures. I will give you a little bit of a update
about our results and then I'll address very briefly some controversies. Dr. Gelbart and Chan from Hong Kong and UCLA have proposed and popularized the use of a 30 degree laparoscopic camera for a better visualization of the structures
and I'll show you some of those pictures. From 2007 on, we've done 125 of these procedures. We always do venography first including intervascular intervention to open up the vein, and then a transaxillary first rib resection, and only do post-operative venography if the vein reclots.
So this is a 19 year old woman who's case I'm going to use to illustrate our approach. She developed acute onset left arm swelling, duplex and venogram demonstrated a collusion of the subclavian axillary veins. Percutaneous mechanical thrombectomy
and then balloon angioplasty were performed with persistent narrowing at the thoracic outlet. So a day later, she was taken to the operating room, a small incision made in the axilla, we air interiorly to avoid injury to the long thoracic nerve.
As soon as you dissect down to the chest wall, you can identify and protect the vein very easily. I start with electrocautery on the peripheral margin of the rib, and use that to start both digital and Matson elevator dissection of the periosteum pleura
off the first rib, and then get around the anterior scalene muscle under direct visualization with a right angle and you can see that the vein and the artery are identified and easily protected. Here's the 30 degree laparoscopic image
of getting around the anterior scalene muscle and performing the electrocautery and you can see the pulsatile vein up here anterior and superficial to the anterior scalene muscle. Here is a right angle around the first rib to make sure there are no structures
including the pleura still attached to it. I always divide, or try to divide, the posterior aspect of the rib first because I feel like then I can manipulate the ribs superiorly and inferiorly, and get the rib shears more anterior for the anterior cut
because that's most important for decompressing the vein. Again, here's the 30 degree laparoscopic view of the rib shears performing first the posterior cut, there and then the anterior cut here. The portion of rib is removed, and you can see both the artery and the vein
are identified and you can confirm that their decompressed. We insufflate with water or saline, and then perform valsalva to make sure that they're hasn't been any pneumothorax, and then after putting a drain in,
I actually also turn the patient supine before extirpating them to make sure that there isn't a pneumothorax on chest x-ray. You can see the Jackson-Pratt drain in the left axilla. One month later, duplex shows a patent vein. So we've had pretty good success with this approach.
23 patients have requires post operative reintervention, but no operative venous reconstruction or bypass has been performed, and 123 out of 125 axillosubclavian veins have been patent by duplex at last follow-up. A brief comment on controversies,
first of all, the surgical approach we continue to believe that a transaxillary approach is cosmetically preferable and just as effective as a paraclavicular or anterior approach, and we have started being more cautious
about postoperative anticoagulation. So we've had three patients in that series that had to go back to the operating room for washout of hematoma, one patient who actually needed a VATS to treat a hemathorax,
and so in recent times we've been more cautious. In fact 39 patients have been discharged only with oral antiplatelet therapy without any plan for definitive therapeutic anticoagulation and those patients have all done very well. Obviously that's contraindicated in some cases
of a preoperative PE, or hematology insistence, or documented hypercoagulability and we've also kind of included that, the incidence of postop thrombosis of the vein requiring reintervention, but a lot of patients we think can be discharged
on just antiplatelets. So again, our approach to this is a transaxillary first rib resection after a venogram and a vascular intervention. We think this cosmetically advantageous. Surgical venous reconstruction has not been required
in any case, and we've incorporated the use of a 30 degree laparoscopic camera for better intraoperative visualization, thanks.
- So Beyond Vascular procedures, I guess we've conquered all the vascular procedures, now we're going to conquer the world, so let me take a little bit of time to say that these are my conflicts, while doing that, I think it's important that we encourage people to access the hybrid rooms,
It's much more important that the tar-verse done in the Hybrid Room, rather than moving on to the CAT labs, so we have some idea basically of what's going on. That certainly compresses the Hybrid Room availability, but you can't argue for more resources
if the Hybrid Room is running half-empty for example, the only way you get it is by opening this up and so things like laser lead extractions or tar-verse are predominantly still done basically in our hybrid rooms, and we try to make access for them. I don't need to go through this,
you've now think that Doctor Shirttail made a convincing argument for 3D imaging and 3D acquisition. I think the fundamental next revolution in surgery, Every subspecialty is the availability of 3D imaging in the operating room.
We have lead the way in that in vascular surgery, but you think how this could revolutionize urology, general surgery, neurosurgery, and so I think it's very important that we battle for imaging control. Don't give your administration the idea that
you're going to settle for a C-arm, that's the beginning of the end if you do that, this okay to augment use C-arms to augment your practice, but if you're a finishing fellow, you make sure you go to a place that's going to give you access to full hybrid room,
otherwise, you are the subservient imagers compared to radiologists and cardiologists. We need that access to this high quality room. And the new buzzword you're going to hear about is Multi Modality Imaging Suites, this combination of imaging suites that are
being put together, top left deserves with MR, we think MR is the cardiovascular imaging modality of the future, there's a whole group at NIH working at MR Guided Interventions which we're interested in, and the bottom right is the CT-scan in a hybrid op
in a hybrid room, this is actually from MD Anderson. And I think this is actually the Trauma Room of the future, makes no sense to me to take a patient from an emergency room to a CT scanner to an and-jure suite to an operator it's the most dangerous thing we do
with a trauma patient and I think this is actually a position statement from the Trauma Society we're involved in, talk about how important it is to co-localize this imaging, and I think the trauma room of the future is going to be an and-jure suite
down with a CT scanner built into it, and you need to be flexible. Now, the Empire Strikes Back in terms of cloud-based fusion in that Siemans actually just released a portable C-arm that does cone-beam CT. C-arm's basically a rapidly improving,
and I think a lot of these things are going to be available to you at reduced cost. So let me move on and basically just show a couple of examples. What you learn are techniques, then what you do is look for applications to apply this, and so we've been doing
translumbar embolization using fusion and imaging guidance, and this is a case of one of my partners, he'd done an ascending repair, and the patient came back three weeks later and said he had sudden-onset chest pain and the CT-scan showed that there was a
sutured line dehiscence which is a little alarming. I tried to embolize that endovascular, could not get to that tiny little orifice, and so we decided to watch it, it got worse, and bigger, over the course of a week, so clearly we had to go ahead and basically and fix this,
and we opted to use this, using a new guidance system and going directly parasternal. You can do fusion of blood vessels or bones, you can do it off anything you can see on flu-roid, here we actually fused off the sternal wires and this allows you to see if there's
respiratory motion, you can measure in the workstation the depth really to the target was almost four and a half centimeters straight back from the second sternal wire and that allowed us really using this image guidance system when you set up what's called the bullseye view,
you look straight down the barrel of a needle, and then the laser turns on and the undersurface of the hybrid room shows you where to stick the needle. This is something that we'd refined from doing localization of lung nodules
and I'll show you that next. And so this is the system using the C-star, we use the breast, and the localization needle, and we can actually basically advance that straight into that cavity, and you can see once you get in it,
we confirmed it by injecting into it, you can see the pseudo-aneurism, you can see the immediate stain of hematoma and then we simply embolize that directly. This is probably safer than going endovascular because that little neck protects about
the embolization from actually taking place, and you can see what the complete snan-ja-gram actually looked like, we had a pig tail in the aura so we could co-linearly check what was going on and we used docto-gramming make sure we don't have embolization.
This patient now basically about three months follow-up and this is a nice way to completely dissolve by avoiding really doing this. Let me give you another example, this actually one came from our transplant surgeon he wanted to put in a vas,
he said this patient is really sick, so well, by definition they're usually pretty sick, they say we need to make a small incision and target this and so what we did was we scanned the vas, that's the hardware device you're looking at here. These have to be
oriented with the inlet nozzle looking directly into the orifice of the mitro wall, and so we scanned the heart with, what you see is what you get with these devices, they're not deformed, we take a cell phone and implant it in your chest,
still going to look like a cell phone. And so what we did, image fusion was then used with two completely different data sets, it mimicking the procedure, and we lined this up basically with a mitro valve, we then used that same imaging guidance system
I was showing you, made a little incision really doing onto the apex of the heart, and to the eur-aph for the return cannula, and this is basically what it looked like, and you can actually check the efficacy of this by scanning the patient post operatively
and see whether or not you executed on this basically the same way, and so this was all basically developed basing off Lung Nodule Localization Techniques with that we've kind of fairly extensively published, use with men can base one of our thoracic surgeons
so I'd encourage you to look at other opportunities by which you can help other specialties, 'cause I think this 3D imaging is going to transform what our capabilities actually are. Thank you very much indeed for your attention.
- Thank you very much, Frank, ladies and gentlemen. Thank you, Mr. Chairman. I have no disclosure. Standard carotid endarterectomy patch-plasty and eversion remain the gold standard of treatment of symptomatic and asymptomatic patient with significant stenosis. One important lesson we learn in the last 50 years
of trial and tribulation is the majority of perioperative and post-perioperative stroke are related to technical imperfection rather than clamping ischemia. And so the importance of the technical accuracy of doing the endarterectomy. In ideal world the endarterectomy shouldn't be (mumbling).
It should contain embolic material. Shouldn't be too thin. While this is feasible in the majority of the patient, we know that when in clinical practice some patient with long plaque or transmural lesion, or when we're operating a lesion post-radiation,
it could be very challenging. Carotid bypass, very popular in the '80s, has been advocated as an alternative of carotid endarterectomy, and it doesn't matter if you use a vein or a PTFE graft. The result are quite durable. (mumbling) showing this in 198 consecutive cases
that the patency, primary patency rate was 97.9% in 10 years, so is quite a durable procedure. Nowadays we are treating carotid lesion with stinting, and the stinting has been also advocated as a complementary treatment, but not for a bail out, but immediately after a completion study where it
was unsatisfactory. Gore hybrid graft has been introduced in the market five years ago, and it was the natural evolution of the vortec technique that (mumbling) published a few years before, and it's a technique of a non-suture anastomosis.
And this basically a heparin-bounded bypass with the Nitinol section then expand. At King's we are very busy at the center, but we did 40 bypass for bail out procedure. The technique with the Gore hybrid graft is quite stressful where the constrained natural stint is inserted
inside internal carotid artery. It's got the same size of a (mumbling) shunt, and then the plumbing line is pulled, and than anastomosis is done. The proximal anastomosis is performed in the usual fashion with six (mumbling), and the (mumbling) was reimplanted
selectively. This one is what look like in the real life the patient with the personal degradation, the carotid hybrid bypass inserted and the external carotid artery were implanted. Initially we very, very enthusiastic, so we did the first cases with excellent result.
In total since November 19, 2014 we perform 19 procedure. All the patient would follow up with duplex scan and the CT angiogram post operation. During the follow up four cases block. The last two were really the two very high degree stenosis. And the common denominator was that all the patients
stop one of the dual anti-platelet treatment. They were stenosis wise around 40%, but only 13% the significant one. This one is one of the patient that developed significant stenosis after two years, and you can see in the typical position at the end of the stint.
This one is another patient who develop a quite high stenosis at proximal end. Our patency rate is much lower than the one report by Rico. So in conclusion, ladies and gentlemen, the carotid endarterectomy remain still the gold standard,
and (mumbling) carotid is usually an afterthought. Carotid bypass is a durable procedure. It should be in the repertoire of every vascular surgeon undertaking carotid endarterectomy. Gore hybrid was a promising technology because unfortunate it's been just not produced by Gore anymore,
and unfortunately it carried quite high rate of restenosis that probably we should start to treat it in the future. Thank you very much for your attention.
- [Presenter] Thank you very much, Mr. Chairman, and ladies and gentlemen, and Frank Veith for this opportunity. Before I start my talk, actually, I can better sit down, because Hans and I worked together. We studied in the same city, we finished our medical study there, we also specialized in surgery
in the same city, we worked together at the same University Hospital, so what should I tell you? Anyway, the question is sac enlargement always benign has been answered. Can we always detect an endoleak, that is nice. No, because there are those hidden type II's,
but as Hans mentioned, there's also a I a and b, position dependent, possible. Hidden type III, fabric porosity, combination of the above. Detection, ladies and gentlemen, is limited by the tools we have, and CTA, even in the delayed phase
and Duplex-scan with contrast might not always be good enough to detect these lesions, these endoleaks. This looks like a nice paper, and what we tried to do is to use contrast-enhanced agents in combination with MRI. And here you see the pictures. And on the top you see the CTA, with contrast,
and also in the delayed phase. And below, you see this weak albumin contrast agent in an MRI and shows clearly where the leak is present. So without this tool, we were never able to detect an endoleak with the usual agents. So, at this moment, we don't know always whether contrast
in the Aneurysm Sac is only due to a type II. I think this is an important message that Hans pushed upon it. Detection is limited by the tools we have, but the choice and the success of the treatment is dependent on the kind of endoleak, let that be clear.
So this paper has been mentioned and is using not these advanced tools. It is only using very simple methods, so are they really detecting type II endoleaks, all of them. No, of course not, because it's not the golden standard. So, nevertheless, it has been published in the JVS,
it's totally worthless, from a scientific point of view. Skip it, don't read it. The clinical revelance of the type II endoleak. It's low pressure, Hans pointed it out. It works, also in ruptured aneurysms, but you have to be sure that the type II is the only cause
of Aneurysm Sac Expansion. So, is unlimited Sac Expansion harmless. I agree with Hans that it is not directly life threatening, but it ultimately can lead to dislodgement and widening of the neck and this will lead to an increasing risk for morbidity and even mortality.
So, the treatment of persistent type II in combination with Sac Expansion, and we will hear more about this during the rest of the session, is Selective Coil-Embolisation being preferred for a durable solution. I'm not so much a fan of filling the Sac, because as was shown by Stephan Haulan, we live below the dikes
and if we fill below the dikes behind the dikes, it's not the solution to prevent rupture, you have to put something in front of the dike, a Coil-Embolisation. So classic catheterisation of the SMA or Hypogastric, Trans Caval approach is now also popular,
and access from the distal stent-graft landing zone is our current favorite situation. Shows you quickly a movie where we go between the two stent-grafts in the iliacs, enter the Sac, and do the coiling. So, prevention of the type II during EVAR
might be a next step. Coil embolisation during EVAR has been shown, has been published. EVAS, is a lot of talks about this during this Veith meeting and the follow-up will tell us what is best. In conclusions, the approach to sac enlargement
without evident endoleak. I think unlimited Sac expansion is not harmless, even quality of life is involved. What should your patient do with an 11-centimeter bilp in his belly. Meticulous investigation of the cause of the Aneurysm Sac
Expansion is mandatory to achieve a, between quote, durable treatment, because follow-up is crucial to make that final conclusion. And unfortunately, after treatment, surveillance remains necessary in 2017, at least. And this is Hans Brinker, who put his finger in the dike,
to save our country from a type II endoleak, and I thank you for your attention.
- Dear Chairman, Ladies and Gentlemen, Thank you Doctor Veith. It's a privilege to be here. So, the story is going to be about Negative Pressure Wound Non-Excisional Treatment from Prosthetic Graft Infection, and to show you that the good results are durable. Nothing to disclose.
Case demonstration: sixty-two year old male with fem-fem crossover PTFE bypass graft, Key infection in the right groin. What we did: open the groin to make the debridement and we see the silergy treat, because the graft is infected with the microbiology specimen
and when identified, the Enterococcus faecalis, Staphylococcus epidermidis. We assess the anastomosis in the graft was good so we decided to put foam, black foam for irrigation, for local installation of antiseptics. This our intention-to treat protocol
at the University hospital, Zurich. Multi-staged Negative Pressure for the Wound Therapy, that's meets vascular graft infection, when we open the wound and we assess the graft, and the vessel anastomosis, if they are at risk or not. If they are not at risk, then we preserve the graft.
If they are at risk and the parts there at risk, we remove these parts and make a local reconstruction. And this is known as Szilagyi and Samson classification, are mainly validated from the peripheral surgery. And it is implemented in 2016 guidelines of American Heart Association.
But what about intracavitary abdominal and thoracic infection? Then other case, sixty-one year old male with intracavitary abdominal infection after EVAR, as you can see, the enhancement behind the aortic wall. What we are doing in that situation,
We're going directly to the procedure that's just making some punctures, CT guided. When we get the specimen microbiological, then start with treatment according to the microbiology findings, and then we downgrade the infection.
You can see the more air in the aneurism, but less infection periaortic, then we schedule the procedure, opening the aneurysm sac, making the complete removal of the thrombus, removing of the infected part of the aneurysm, as Doctor Maelyna said, we try to preserve the graft.
That exactly what we are doing with the white foam and then putting the black foam making the Biofilm breakdown with local installation of antiseptics. In some of these cases we hope it is going to work, and, as you see, after one month
we did not have a good response. The tissue was uneager, so we decided to make the removal of the graft, but, of course, after downgrading of this infection. So, we looked at our data, because from 2012 all the patients with
Prostetic Graft infection we include in the prospective observational cohort, known VASGRA, when we are working into disciplinary with infectious disease specialist, microbiologists, radiologist and surgical pathologist. The study included two group of patients,
One, retrospective, 93 patient from 1999 to 2012, when we started the VASGRA study. And 88 patient from April 2012 to Seventeen within this register. Definitions. Baseline, end of the surgical treatment and outcome end,
the end of microbiological therapy. In total, 181 patient extracavitary, 35, most of them in the groin. Intracavitary abdominal, 102. Intracavitary thoracic, 44. If we are looking in these two groups,
straight with Negative Pressure Wound Therapy and, no, without Negative Pressure Wound Therapy, there is no difference between the groups in the male gender, obesity, comorbidity index, use of endovascular graft in the type Samson classification,
according to classification. The only difference was the ratio of hospitalization. And the most important slide, when we show that we have the trend to faster cure with vascular graft infection in patients with Negative Pressure Wound Therapy
If we want to see exactly in the data we make uni variant, multi variant analysis, as in the initial was the intracavitary abdominal. Initial baseline. We compared all these to these data. Intracavitary abdominal with no Pressure Wound Therapy
and total graft excision. And what we found, that Endovascular indexoperation is not in favor for faster time of cure, but extracavitary Negative Pressure Wound Therapy shows excellent results in sense of preserving and not treating the graft infection.
Having these results faster to cure, we looked for the all cause mortality and the vascular graft infection mortality up to two years, and we did not have found any difference. What is the strength of this study, in total we have two years follow of 87 patients.
So, to conclude, dear Chairman, Ladies and Gentlemen, Explant after downgrading giving better results. Instillation for biofilm breakdown, low mortality, good quality of life and, of course, Endovascular vascular graft infection lower time to heal. Thank you very much for your attention.
- I'd like to thank Dr. Veith and the committee for the privilege of presenting this. I have no disclosures. Vascular problems and the type of injuries could be varied. We all need to have an awareness of acute and chronic injuries,
whether they're traumatic, resulting with compression, occlusion, tumoral and malformation results, or vasospastic. I'd like to present a thoracoscopic manipulation of fractured ribs to prevent descending aortic injury
in a patient with chest trauma. You know, we don't think about this but they can have acute or delayed onset of symptoms and the patient can change and suddenly deteriorate with position changes or with mechanical ventilation,
and this is a rather interesting paper. Here you can see the posterior rib fracture sitting directly adjacent to the aorta like a knife. You can imagine the catastrophic consequences if that wasn't recognized and treated appropriately.
We heard this morning in the venous session that the veins change positions based on the arteries. Well, we need to remember that the arteries and the whole vascular bundle changes position based on the spine
and the bony pieces around them. This is especially too when you're dealing with scoliosis and scoliotic operations and the body positioning whether it's supine or prone the degree of hypo or hyperkyphosis
and the vertebral angles and the methods of instrumentation all need to be considered and remembered as the aorta will migrate based on the body habits of the patient. Screws can cause all kinds of trouble.
Screws are considered risky if they're within one to three millimeters of the aorta or adjacent tissues, and if you just do a random review up to 15% of screws that are placed fall into this category.
Vertebral loops and tortuosity is either a congenital or acquired anomaly and the V2 segment of the vertebral is particularly at risk, most commonly in women in their fifth and sixth decades,
and here you can see instrumentation of the upper cervical spine, anterior corpectomy and the posterior exposures are all associated with a significant and lethal, at times, vertebral artery injuries.
Left subclavian artery injury from excessively long thoracic pedicle screws placed for proximal thoracic scoliosis have been reported. Clavicular osteosynthesis with high neurovascular injury especially when the plunge depth isn't kept in mind
in the medial clavicle have been reported and an awareness and an ability to anticipate injury by looking at the safe zone and finding this on the femur
with your preoperative imaging is a way to help prevent those kinds of problems. Injuries can be from stretch or retraction. Leave it to the French. There's a paper from 2011 that describes midline anterior approach
from the right side to the lumbar spine, interbody fusion and total disc replacement as safer. The cava is more resistant to injury than the left iliac vein and there's less erectile dysfunction reported. We had a patient present recently
with the blue bumps across her abdomen many years after hip complicated course. She'd had what was thought to be an infected hip that was replaced, worsening lower extremity edema, asymmetry of her femoral vein on duplex
and her heterogeneous mask that you can see here on imaging. The iliac veins were occluded and compressed and you could see in the bottom right the varicosities that she was concerned about. Another case is a 71-year-old male who had a post-thrombotic syndrome.
It was worsened after his left hip replacement and his wife said he's just not been the same since. Initially imaging suggests that this was a mass and a tumor. He underwent biopsy
and it showed ghost cells. Here you can see the venogram where we tried to recanalize this and we were unsuccessful because this was actually a combination of bone cement and inflammatory reaction.
Second patient in this category, bless you, is a 67-year-old female who had left leg swelling again after a total hip replacement 20 plus years ago. No DVTs but here you can see the cement compressing the iliac vein.
She had about a 40% patency when you put her through positioning and elected not to have anything done with that. Here you could see on MR how truly compressed this is. IVA suggested it was a little less tight than that.
So a vascular injury occurs across all surgical specialties. All procedures carry risk of bleeding and inadvertent damage to vessels. The mechanisms include tearing, stretching, fracture of calcific plaques,
direct penetration and thermal injury. The types of injuries you hear are most common after hip injuries, they need to be recognized in the acute phase as looking for signs of bleeding or ischemia. Arterial lesions are commonly prone then.
Bone cement can cause thermal injury, erosion, compression and post-implant syndrome. So again, no surgery is immune. You need to be aware and especially when you look at patients in the delayed time period
to consider something called particle disease. This has actually been described in the orthopedic literature starting in the 70s and it's a complex interaction of inflammatory pathways directed at microparticles that come about
through prosthetic wear. So not only acute injury but acute and chronic symptoms. Thank you for the privilege of the floor.
- Thank you, thanks for the opportunity to present. I have no disclosures. So, we all know that wounds are becoming more prevalent in our population, about 5% of the patient population has these non-healing wounds at a very significant economic cost, and it's a really high chance of lower extremity amputation
in these patients compared to other populations. The five-year survival following amputation from a foot ulcer is about 50%, which is actually a rate that's worse than most cancer, so this is a really significant problem. Now, even more significant than just a non-healing wound
is a wound that has both a venous and an arterial component to it. These patients are about at five to seven times the risk of getting an amputation, the end patients with either isolated venous disease or isolated PAD. It's important because the venous insufficiency component
brings about a lot more inflammation, and as we know, this is associated with either superficial or deep reflux, a history of DVT or incompetent perforators, but this adds an increasing complexity to these ulcers that refuse to heal.
So, it's estimated now about 15% of these ulcers are more of a mixed etiology, we define these as anyone who has some component of PAD, meaning an ABI of under point nine, and either superficial or deep reflux or a DVT on duplex ultrasound.
So we're going to talk for just a second about how do we treat these. Do we revascularize them first, do we do compression therapy? It has been shown in many, many studies, as with most things, that a multi-disciplinary approach
will improve the outcome of these patients, and the first step in any algorithm for these patients involves removing necrotic and infected tissue, dressings, if compression is feasible, based on the PAD level, you want to go ahead and do this secondary, if it's not, then you need to revascularize first,
and I'm going to show you our algorithm at Michigan that's based on summa the data. But remember that if the wounds fail to heal despite all of this, revascularization is a good option. So, based on the data, the algorithm that we typically use is if an ABI is less than point five
or a toe pressure is under 50, you want to revascularize first, I'll talk for a minute about the data of percutaneous versus open in these patients, but these are the patients you want to avoid compression in as a first line therapy.
If you have more moderate PAD, like in the point five to point eight range, you want to consider compression at the normal 40 millimeters of mercury, but you may need to modify it. It's actually been shown that that 40 millimeter of mercury
compression actually will increase flow to those wounds, so, contrary to what had previously been thought. So, revascularization, the data's pretty much equivocal right now, for these patients with these mixed ulcers, of whether you want to do endovascular or open. In diabetics, I think the data strongly favors
doing an open bypass if they have a good autogenous conduit and a good target, but you have to remember, in these patients, they have so much inflammation in the leg that wound healing from the surgical incisions is going to be significantly more difficult
than in a standard PAD patient, but the data has shown that about 60% of these ulcers heal at one year following revascularization. So, compression therapy, which is the mainstay either after revascularization in the severe PAD group or as a first line in the moderate group,
is really important 'cause it, again, increases blood flow to the wound. They've shown that that 40 millimeters of mercury compression is associated with a significant healing rate if you can do that, you additionally have to be careful, though,
about padding your bony areas, also, as we know, most patients don't actually keep their compression level at that 40, so there are sensors and other wearable technologies that are coming about that help patients with that, keeping in mind too, that the venous disease component
in these patients is really important, it's really important to treat the superficial venous reflux, EVLT is kind of the standard for that, treatment of perforators greater than five, all of that will help.
And I'm not going to go into any details of wound dressings, but there are plenty of new dressings that are available that can be used in conjunction with compression therapy. So, our final algorithm is we have a patient with these mixed arterial venous ulcers, we do woundcare debridement, determine the degree of PAD,
if it's severe, they go down the revascularization pathway, followed by compression, if it's moderate, then they get compression therapy first, possible treatment of venous disease, if it still doesn't heal at about 35 weeks, then you have to consider other things,
like biopsy for cancer, and then also consider revacularization. So, these ulcers are on a rise, they're a common problem, probably we need randomized control trials to figure out the optimal treatment strategies.
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