- So this was born out of the idea that there were some patients who come to us with a positive physical exam or problems on dialysis, bleeding after dialysis, high pressures, low flows, that still have normal fistulograms. And as our nephrology colleagues teach us, each time you give a patient some contrast,
you lose some renal function that they maintain, even those patients who are on dialysis have some renal function. And constantly giving them contrasts is generally not a good thing. So we all know that intimal hyperplasia
is the Achilles Heel of dialysis access. We try to do surveillance. Debbie talked about the one minute check and how effective dialysis is. Has good sensitivity on good specificity, but poor sensitivity in determining
dialysis access problems. There are other measured parameters that we can use which have good specificity and a little better sensitivity. But what about ultrasound? What about using ultrasound as a surveillance tool and how do you use it?
Well the DOQI guidelines, the first ones, not the ones that are coming out, I guess, talked about different ways to assess dialysis access. And one of the ways, obviously, was using duplex ultrasound. Access flows that are less than 600
or if they're high flows with greater than 20% decrease, those are things that should stimulate a further look for clinical stenosis. Even the IACAVAL recommendations do, indeed, talk about volume flow and looking at volume flow. So is it volume flow?
Or is it velocity that we want to look at? And in our hands, it's been a very, very challenging subject and those of you who are involved with Vasculef probably have the same thing. Medicare has determined that dialysis shouldn't, dialysis access should not be surveilled with ultrasound.
It's not medically necessary unless you have a specific reason for looking at the dialysis access, you can't simply surveil as much as you do a bypass graft despite the work that's been done with bypass graft showing how intervening on a failing graft
is better than a failed graft. There was a good meta-analysis done a few years ago looking at all these different studies that have come out, looking at velocity versus volume. And in that study, their conclusion, unfortunately, is that it's really difficult to tell you
what you should use as volume versus velocity. The problem with it is this. And it becomes, and I'll show you towards the end, is a simple math problem that calculating volume flows is simply a product of area and velocity. In terms of area, you have to measure the luminal diameter,
and then you take the luminal diameter, and you calculate the area. Well area, we all remember, is pi r squared. So you now divide the diameter in half and then you square it. So I don't know about you,
but whenever I measure something on the ultrasound machine, you know, I could be off by half a millimeter, or even a millimeter. Well when you're talking about a four, five millimeter vessel, that's 10, 20% difference.
Now you square that and you've got a big difference. So it's important to use the longitudinal view when you're measuring diameter. Always measure it if you can. It peaks distally, and obviously try to measure it in an non-aneurysmal area.
Well, you know, I'm sure your patients are the same as mine. This is what some of our patients look like. Not many, but this is kind of an exaggerated point to make the point. There's tortuosity, there's aneurysms,
and the vein diameter varies along the length of the access that presents challenges. Well what about velocity? Well, I think most of us realize that a velocity between 100 to 300 is probably normal. A velocity that's over 500, in this case is about 600,
is probably abnormal, and probably represents a stenosis, right? Well, wait a minute, not necessarily. You have to look at the fluid dynamic model of this, and look at what we're actually looking at. This flow is very different.
This is not like any, not like a bypass graft. You've got flow taking a 180 degree turn at the anastomosis. Isn't that going to give you increased turbulence? Isn't that going to change your velocity? Some of the flow dynamic principles that are important
to understand when looking at this is that the difference between plug and laminar flow. Plug flow is where every bit is moving at the same velocity, the same point from top to bottom. But we know that's not true. We know that within vessels, for the most part,
we have laminar flow. So flow along the walls tends to be a little bit less than flow in the middle. That presents a problem for us. And then when you get into the aneurysmal section, and you've got turbulent flow,
then all bets are off there. So it's important, when you take your sample volume, you take it across the whole vessel. And then you get into something called the Time-Averaged mean velocity which is a term that's used in the ultrasound literature.
But it basically talks about making sure that your sample volume is as wide as it can be. You have to make sure that your angle is as normal in 60 degrees because once you get above 60 degrees, you start to throw it off.
So again, you've now got angulation of the anastomosis and then the compliance of a vein and a graft differs from the artery. So we use the two, we multiply it, and we come up with the volume flow. Well, people have said you should use a straight segment
of the graft to measure that. Five centimeters away from the anastomosis, or any major branches. Some people have actually suggested just using a brachial artery to assess that. Well the problems in dialysis access
is there are branches and bifurcations, pseudoaneurysms, occlusions, et cetera. I don't know about you, but if I have a AV graft, I can measure the volume flow at different points in the graft to get different numbers. How is that possible?
Absolutely not possible. You've got a tube with no branches that should be the same at the beginning and the end of the graft. But again, it becomes a simple math problem. The area that you're calculating is half the diameter squared.
So there's definitely measurement area with the electronic calipers. The velocity, you've got sampling error, you've got the anatomy, which distorts velocity, and then you've got the angle with which it is taken. So when you start multiplying all this,
you've got a big reason for variations in flow. We looked at 82 patients in our study. We double blinded it. We used a fistulagram as the gold standard. The duplex flow was calculated at three different spots. Duplex velocity at five different spots.
And then the diameters and aneurysmal areas were noted. This is the data. And basically, what it showed, was something totally non-significant. We really couldn't say anything about it. It was a trend toward lower flows,
how the gradients (mumbles) anastomosis, but nothing we could say. So as you all know, you can't really prove the null hypothesis. I'm not here to tell you to use one or use the other, I don't think that volume flow is something that
we can use as a predictor of success or failure, really. So in conclusion, what we found, is that Debbie Brow is right. Clinical examinations probably still the best technique. Look for abnormalities on dialysis. What's the use of duplex ultrasound in dialysis or patients?
And I think we're going to hear that in the next speaker. But probably good for vein mapping. Definitely good for vein mapping, arterial inflow, and maybe predicting maturation. Thank you very much.
- These are my disclosure, did not influence my work. I would like to thank you for Dr. Weith for the invitation. And I think this is time we cannot ignore anymore one of our major complication during the procedures not just TAVIing with any other surgeries. My tool is the transcranial doppler and I just call it the
stethoscope to the brain because it's really listen to the flow, measure the speed of the flow, measure the direction of the flow. But it also tells me by the resistance if the vessel in the brain occluded or open.
So this is the example how an embolus traveling in the middle cerebral artery or the ACA look like. And again there's not many of those good emboli. The only good emboli we using for PFO testing. But-- sorry--
My pointer would like to show you that on the right bottom corner this is how an MC occlusion looks like real time when a waveform just disappears. This is the example also a teaching tool that you can was the contrast injection and how the lots of air with the contrast injection look like.
But again going back to the TAVI, you can see that the cerebral DWI lesion 90, 80 almost 86 percent, it's a really high number for this procedure. And when you divide them by the transcranial doppler you can see the balloon valvuloplasty and the placement
of the valve comes with the highest emboli count. During their study in Houston this is how they divided the procedure to different phases. And I just want to walk you through a procedure. And this is one of the first challenge, just crossing the valve.
Look at those white lines on the TCD real time while your wire trying to cross your valve. Those are all microemboli. During the BAV you can see there's a hypoperfusion. So hypoperfusion the brain really doesn't like hypoperfusion too much.
So but when you see the folly sword you can see the microemboli too. So again not just the microembolization but the hemodynamics, how your hypoperfusion is really important. And a successful BAV and a valve placement shows that you
have end diastolic flow. Here comes the arch crossing by the TAVI. And you can see just crossing the arch it's also comes with embolization. And why your positioning? The positioning itself again comes
with a shower of microembolization. And it also see that the diastolic profusion is also suffers. And a low diastolic profusion is hyperprofusion again. And why the placement you see the rapid pacing, this is comes with again hyperprofusion and microemboli.
Those are the incidents how we can see by deflating the balloon you're going to see the incidents of microembolization. The different valves again results of no flow pattern. And this is again, in this moment you can see the flow is gone.
Your concern is this something that we just lost a signal. The flow comes back and these are lack of signals and lack of flow of temporarily. But we can also assess how the AI is treated when there's no diastolic flow. That's not good,
that's correlating nicely. And the final results when finally you have a good end diastolic flow pattern that tells you that your surgery's successful. Again different devices can be studied by the DCD, a low deployment versus the balloon deployment.
And this is my most scary picture when you see that the valve is crossing the arch and one of the signals you're going to see and disappear. So this is why we encourage bilateral signal, bilateral MCM monitoring. And here when the microemboli comes,
your signal disappearing, that resulting in a stroke. And you can again act and go to the neuro angio suite. So our data also showed that despite that we have a really low number of stroke and TIA's, we didn't see too much difference.
But phase five, this is when the deployment happens with the high emboli count. But also you cannot ignore that the phase two, when you just moving your catheter causing the valve come through the high emboli count as well.
And just a different way of showing you that majority of the HITS again comes with the valve deployment. But also the low flow stages when we have hyperprofusion we just cannot ignore. Thank you so much for your attention.
- Thank you (mumbles). The purpose of deep venous valve repair is to correct the reflux. And we have different type of reflux. We know we have primary, secondary, the much more frequent and the rear valve agenesia. In primary deep venous incompetence,
valves are usually present but they are malfunctioning and the internal valvuloplasty is undoubtedly the best option. If we have a valve we can repair it and the results are undoubtedly the better of all deep vein surgery reconstruction
but when we are in the congenital absence of valve which is probably the worst situation or we are in post-thrombotic syndrome where cusps are fully destroyed, the situation is totally different. In this situation, we need alternative technique
to provide a reflux correction that may be transposition, new valve or valve transplants. The mono cuspid valve is an option between those and we can obtain it by parietal dissection. We use the fibrotic tissue determined by the
sickening of the PTS event obtaining a kind of flap that we call valve but as you can realize is absolutely something different from a native valve. The morphology may change depending on the wall feature and the wall thickness
but we have to manage the failure of the mono cuspid valve which is mainly due to the readhesion of the flap which is caused by the fact that if we have only a mono cuspid valve, we need a deeper pocket to reach the contralateral wall so bicuspid valve we have
smaller cusps in mono cuspid we have a larger one. And how can we prevent readhesion? In our first moment we can apply a technical element which is to stabilize the valve in the semi-open position in order not to have the collapse of the valve with itself and then we had decide to apply an hemodynamic element.
Whenever possible, the valve is created in front of a vein confluence. In this way we can obtain a kind of competing flow, a better washout and a more mobile flap. This is undoubtedly a situation that is not present in nature but helps in providing non-collapse
and non-thrombotic events in the cusp itself. In fact, if we look at the mathematical modeling in the flow on valve you can see how it does work in a bicuspid but when we are in a mono cuspid, you see that in the bottom of the flap
we have no flow and here there is the risk of thrombosis and here there is the risk of collapse. If we go to a competing flow pattern, the flap is washed out alternatively from one side to the other side and this suggest us the idea to go through a mono cuspid
valve which is not just opens forward during but is endovascular and in fact that's what we are working on. Undoubtedly open surgery at the present is the only available solution but we realized that obviously to have the possibility
to have an endovascular approach may be totally different. As you can understand we move out from the concept to mimic nature. We are not able to provide the same anatomy, the same structure of a valve and we have to put
in the field the possibility to have no thrombosis and much more mobile flap. This is the lesson we learn from many years of surgery. The problem is the mobile flap and the thrombosis inside the flap itself. The final result of a valve reconstruction
disregarding the type of method we apply is to obtain an anti-reflux mechanism. It is not a valve, it is just an anti-reflux mechanism but it can be a great opportunity for patient presenting a deep vein reflux that strongly affected their quality of life.
- 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.
- And thanks to Dr. Veith for the opportunity to get involved. Here's my disclosures. Like so many in the audience, for years and years we've had awesome results with the AngioJet from Boston Sci. We know that this rheolytic system works quite well.
However it has a black box warning for PE due to the hemolysis and the adenosine that can be extruded out. It's oftentimes not stand alone. It's not used for stroke and there can be some renal issues. But we've had excellent results with it over the years,
but at the end of the day often times you still need lytics. And I think Professor Davies just eluded to the potential problems not only medical, but legal as well of lytics. Therefore for the past four plus years we've utilized this as well as other thrombectomy devices.
This is the Indigo device from Penumbra. I'm certain by now most of your are familiar with it, but if not what it is it's a braided catheter that's very atraumatic and soft at the tip. It can come straight in or torqued so you can have some directionality to it.
And then what it also has is this separator technology which is really just like a glorified pipe cleaner to be honest. You're going to go in and out with this device as I'll show you here in a second, to clear the lumen while you're
allowing for continuous aspiration through this system. We learned from our neurosurgery colleagues who utilized typically the CAT five, sometimes six for their stroke patients, but now there's CAT three, five, six, and eight. And within the next probably three to four months
there's going to be CAT 10 or possibly even 12 out there. This is what you have. It's all pretty simple. You cross your lesion with the wire. You then bring your catheter across. You connect it to this suction device,
hit the green button and away you go. You get maximal aspiration. And what's nice about it is in particular for the CAT eight with the XTORQ, as you can see you can get out to vessel 25 millimeters in diameter.
So essentially a cava. This shows you how powerful this is. This is one of my patient's with a standard nitinol stent. A Zilver PTX was occluded and you can see how powerful this device
is with maximal aspiration. Turn it off and obviously the self expanding stent goes right back to normal. So after our results with the ALI patients, and we presented our data at the Midwest meeting in St. Louis earlier this fall,
we start looking at our DVT patients and here you can see an effort thrombosis. Somebody here. We went eight French basilic. Ultrasound guided. Put an eight French Indigo in and with no lytics,
were able to clean this out. We then went on to, I put him on a DOAC. Today I'd probably use Lovenox for two weeks. And then he went home. He's a 32 year old.
Went to Disney World with his family and then came back later on for is infraclavicular rib excision. Here's another one of my patients, Lena. She's a 19 year old who started her OPCs on the way back to Bellarmine College in Louisville.
And as you can see here, she is a likely underlying May Thurner lesion. Extensive of femoral DVT. As you look over here to the screen left to screen right, you can see that we crossed it, put our catheter up in the common iliac vein,
as as you can see we're twisting it around to get to the edges of the vessel, the whole iliofemoral system. Here's what you get afterwards. You get antegrade flow. Certainly there's no device yet that's perfect at this.
For this particular patient we gave her 14 milligrams of lytics then did our IVUS then did our wallstent. And she's done quite well. We use it for arms. We use it for legs.
We use it for filters as well as you can see here with this occluded filter. And often times the picture you're going to get is an underlying acute on chronic thrombosis here. And we later on came back and took that filter out. So I think there's no question there's less lytics with it.
Earlier this year we presented at the American Venous Forum in Tucson. Our initial experiences with vacuum-assisted thrombectomy for DVT. And what showed is that often times you can get antegrade flow as I'll show you here.
Some of them are single sessions. But more importantly just as efficacious as it is it's safe. You can see here that we had minimal blood loss, low transfusions, and here's our breakdown. As we use it for all venous pathologies as you can see.
So at the time when we looked at our first 20, you can see that there were some that were single session therapy. And that's before. We've now added the turbo pulse technique where you're going to lace it with
14 milligrams of TPA through a unifused catheter, wait 20 minutes, go around get some coffee, whatever you need to do, come back and then use the Indigo. So at the end of the day, I think as Professor Davies eluded to, there are major complications with lytics.
This is not what we need for our patients. So in 2018 we can either continue to load with dangerous lytics or minimize lytics, adopt continuous aspiration thrombectomy. It's your all's choice. So thanks so much.
- So thank you ladies and gentleman, thank you Doctor Veith for inviting me again this year. These are my disclosures. So more effective thrombolysis by microbubbles and ultrasound has been proven actually effective in earlier studies, treating a myocardial infarction or acute ischemic stroke.
But what are these microbubbles? These are 1 to 10 micrometers, gas-filled bubbles with a lipid shell. It oscillate when subjected to low intensity ultrasound, and can cavitate when subjected to high intensity ultrasound. Initially they were designed for diagnostic use
as intravascular contrast enhancers. However, they have many advantages, non-specifical mechanical effects, to induce thrombus breakdown due to mechanical force of microbubbles if they are subjected to ultrasound. So we conducted the first human trial
in peripheral arterial diseases in Microbubbles and UltraSound-accelerated Thrombolysis, the MUST study for peripheral arterial occlusions. Which is a single phase two trial for actually safety and feasibility study. The MUST-TRIAl consist out of 20 patients
for safety and feasibility, which in 10 patients will be treated with Urokinase, and 10 with Alteplase. And then added, for the first hour, microbubbles and we evaluated the VAS pain scores, duplex echography for circulation or revascularization, microcirculation and daily angiography as usual.
Included were men and women 18 to 85 years. A maximum of two weeks of symptoms of lower limb ischaemia due to thrombosed or occluded lower limb peripheral native arteries or venous or prosthetic bypass grafts. And Rutherford class 1 or 2A. They have to understand the nature of the procedure
and written informed consent. And excluded were all known factors that exclude standard thrombolysis therapy, hypersensitivity to contrast enhanced agents, a recent acute coronary syndrome. Endpoints, again, it's a safety
and then a technical feasibility trial. Also we looked at the organisation, and the treatment duration for technical, angiographic, and clinical success. We looked at the severe adverse event and mortality rates, VAS-pain scores and microcirculation.
If the patients came in, we inform them about the MUST trail, we performed an ECG analysis and informed consent. They fill out some questionnaires and when they come in to the angio-room, we started a thrombolysis with a catheter, the Mc Nemara.
And the first group, the Urokinase 10 patients, we treated with 500 units of bolus and then continued with a 50,000 units of Urokinase per hour. The Alteplase group had started with a 5 milligram bolus and then they continued with 1 milligram per hour
for the first 24 hours. And then, the ultrasound room, they got a bubble infusion for the first hour of treatment. Then we would continue with thrombolysis on a surgical ward, every sixth hour we'd look at if there was revascularization at the duplex ultrasound.
And if signs of revascularization are observed on the duplex ultrasound or on the next day, we routinely perform the angiography. Then we could cessate the thrombolytic therapy, and if necessary, acute or elective additional intervention to correct underlying lesions,
or to establish patencies. We check the wound and then we follow-up these patients every six weeks, three months, 6 months, and one year after thrombolytic therapy. So these are the patient characteristics, mostly of these were male, 70 years,
and five of them were native bypass, and five were a bypass occlusion, venous or prosthetic. And two of them had multiple occlusions, whether Rutherford class 1 or 2A. And these were the first 10 patients that were treated with Urokinase and I will present here
the results of these 10 patients first. So, very important, there were no deaths, no severe adverse events, and it was technical feasible. The flow at the duplex examination was there after 24 hours, but most of our patients actually had it already after 6 hours.
The amputation rate, right now, is zero. And also no bypasses were now needed. So we will continue this MUST trial right now and January we probably will have the inclusion of the group with the Alteplase, which I'll present next year.
And we think that microbubbles with Urokinase is a safe combination right now. We will further include the groups of adults placed and further optimalisation of the microbubbles technique with nanobubbles. Had a talk about that yesterday, so you can look it up.
And nanobubbles are nanoparticles of 5 to 500 nanometers, which are very small, they do not penetrate the endothelial barrier of the doubt and it damage. And it can carry the thrombolytics actually to the side the aorta catheter need it. You can also make the magnetic paste,
which means you can paste these patients on the MRI. Then you can have local treatment of thrombolytic therapy. So thank you for your attention.
- First of all let me thank Dr. Veith for the kind invitation to be here again and it's my great pleasure to share with you the preliminary result of our Indian registry. So these are my disclosures. So as vascular surgeon we have to admit that the Fogarty embolectomy has many possibility
but also some limitation. You can see here in this short video that we were able to remove thrombus, but thrombus was mixed up with plaque, hyperplasia and the final result was a very poor backflow from this vessel.
So already a couple of years ago we published our experience comparing the Fogarty embolectomy with the hybrid treatment that at that time was Fogarty plus a lot of endovascular rescue maneuver and of course hybrid was better, but we were very surprised by this.
What we found that the introvert in geography after Fogarty we had a number of chronic disease this is normal, but we also found a number of residual thrombus because firmly adherent to the arterial wall or just not appropriately reached by the Fogarty balloon embolectomy.
Even the over the Y Fogarty balloon embolectomy cannot work enough well. And then finally we also had a number of case with the injuries. Probably from inappropriate Fogarty balloon maneuver into the vessels so we had to find something more.
We had to find something less traumatic and so we realized that at the same time our colleagues from stroke unit, the neurologist had already a very nice tool in their hands. It's the Penumbra system which has began the market leader in stroke because it's very atraumatic,
dedicated for intracranial vessel navigation and then has a very high aspiration power system. So a couple of years later the company came on the market with the family dedicated to peripheral artery, the Indigo System from three to eight French catheter
designed for peripheral artery. So really improved trackability and atraumatic tip of this catheter. So how does the system work? You have already seen this video, but anyway you have first to engage the clot then you switch on
the aspiration power and then from proximal to distal you can remove all the thrombus, you can use the separator guide wire that breaks up the clot when ingested into the catheter and so the final result is that the tip of catheter is all we part and that you can remove all the thrombus
in very few minutes. Now I want to show to you my very first case it was four years ago and the system was not yet available and I for prefer I had some conflicting result with the other with competitors. I have incomplete reperfusion or hemolysis.
I have very positive feedback from my colleagues from the stroke unit at my University. I had the possibility to borrow the neuro catheters. So in this very first patients, unfit for lysis with a lot of thrombus, fresh thrombus in a vein popliteal area and the tibial artery I used
neural catheters, separate was very easy even at the beginning of our experience and we were able to engage the clot use the separator and removing in a couple of passage old thrombus even from the very distal localizations. So up to now we have used the Indigo family,
Indigo system in a lot of situation I can go through all this the one, but I want to show you how far we can go and it's a very challenging situation within dialysis dependent patients with the calcify kink and tibial artery and thrombus in the plantar arch
we were able to reach the plantar arch with the CAT 3 device and remove all the thrombus. Since then we have decided to collect data in a prospective national registry, the Indian registry. We want to collect 150 case in this prospective registry. We started last year and we actually included any kind
of acute lower limb ischemia embolism, thrombosis, graft endograft thrombosis, distal emboli and secondary to preceding intervention or even incomplete reperfusion after Fogarty and lysis. We evaluated the vessel patency by TIMI score of course we have now 136 patients enrolled by 17 centers active
and Ethiological hypothesis of the ischemia was in the 3/4 of case thrombotic, so the most challenging case. Acute and chronic ischemia mainly in very popliteal area or even below the knee or below the ankle in arteries. And here are preliminary result available for 120 patients.
After the Indigo use we already have a 90% TIMI two or three flow restoration will raise up to 96% after additional PTA or stent or additional lysis. So in conclusion these are only the preliminary result I hope to share with you our final result next year,
but at that moment we can already say that the Indigo is safe and effective option for acute lower limb ischemia, technical success is high even in small arteries, and up to now adverse event related to the device is very low and bleeding and hemolysis are not reported.
- Thank you very much for the privilege of participating in this iconic symposium. I have no disclosures pertinent to this presentation. The Atelier percutaneous endovascular repair for ruptured abdominal aortic aneurysms is a natural evolution of procedural technique due to the success of fully percutaneous endovascular
aortic aneurysm repair in elective cases. This past year, we had the opportunity to publish our data with regard to 30 day outcomes between percutaneous ruptured aneurysm repairs and surgical cutdown repairs utilizing the American College of Surgeons NSQIP database,
which is a targeted database which enrolls about 800 hospitals in the United States, looking at both the univariate and multivariate analyses comparing preoperative demographics, operative-specific variables and postoperative outcomes. There were 502 patients who underwent
ruptured abdominal aortic aneurysms that were included in this review, 129 that underwent percutaneous repair, whereas 373 underwent cutdown repair. As you can see, the majority were still being done by cutdown.
Over the four years, however, there was a gradual increase in the number of patients that were having percutaneous repair used as their primary modality of access, and in fact a more recent stasis has shown to increase up to 50%,
and there certainly was a learning curve during this period of time. Looking at the baseline characteristics of patients with ruptured aneurysms undergoing both modalities, there was not statistically significant difference
with regard to these baseline characteristics. Likewise, with size of the aneurysms, both were of equal sizes. There was no differences with regard to rupture having hypotension, proximal or distal extension of the aneurysms.
What is interesting, however, that the patients that underwent percutaneous repair tended to have regional anesthesia as their anesthesia of choice, rather than that of having a general. Also there was for some unexplained reason
a more significant conversion to open procedures in the percutaneous group as compared to the cutdown group. Looking at adjusted 30-day outcomes for ruptured endovascular aneurysm repairs, when looking at the 30-day mortality,
the operative time, wound complications, hospital length of stay, that was not statistically significant. However, over that four year period of time, there tended to be decreased hospital length of stay as well as decreased wound complications
over four years. So the summary of this study shows that there was an increased use of fully percutaneous access for endovascular repairs for ruptured aneurysms with noninferiority compared to traditional open femoral cutdown approaches.
There is a trending advantage over conventional surgical exposure with decreased access-related complications, as well as decreased hospital length of stay. Now, I'm going to go through some of the technical tips, and this is really going to be focused upon
the trainees in the room, and also perhaps those clinicians who do not do percutaneous access at this time. What's important, I find, is that the utility of duplex ultrasonography, and this is critical to delineate the common
femoral artery access anatomy. And what's important to find is the common femoral artery between the inguinal ligament and this bifurcation to the profunda femoral and superficial femoral arteries. So this is your target area. Once this target area is found,
especially in those patients presenting with ruptured aneurysm, local anesthesia is preferred over general anesthesia with permissive hypotension. This is a critical point that once you use ultrasound, that you'd want to orient your probe to be
90 degrees to the target area and measure the distance between the skin and the top of that artery. Now if you hold that needle at equidistance to that same distance between the skin and the artery and angle that needle at 45 degrees,
this will then allow you to have the proper trajectory to hit the target absolutely where you're imaging the vessel, and this becomes important so you're not off site. Once micropuncture technique is used, it's always a good idea just to use
a quick fluoroscopic imaging to show that your access is actually where you want it to be. If it's not, you can always re-stick the patient again. Once you have the access in place, what can then happen is do a quick angio to show in fact you have reached the target vessel.
This is the routine instructions for use by placing the percutaneous suture-mediated closure system at 45 degree angles from one another, 90 degrees from one another. Once the sheath is in place for ruptured aneurysm, the placement of a ballon occlusion
can be done utilizing a long, at least 12 French sheath so that they'll keep that balloon up in place. What's also good is to keep a neat operative field, and by doing so, you can keep all of these wires and sutures clean and out of the way and also color code the sutures so that you have
ease and ability to close them later. Finally, it's important to replace the dilator back in the sheath prior to having it removed. This is important just so that if there are problems with your percutaneous closure, you can always very quickly replace your sheath back in.
Again, we tend to color code the sutures so we can know which ones go with which. You can also place yet a third percutaneous access closure device if need be by keeping the guide wire in place. One other little trick that I actually learned
from Ben Starnes when visiting his facility is to utilize a Rumel mediated technique by placing a short piece of IV tubing cut length, running the suture through that, and using it like a Rumel, and that frees up your hand as you're closing up
the other side and final with closure. The contraindications to pREVAR. And I just want to conclude that there's increased use of fully percutaneous access for endovascular repair. There's trending advantages over conventional surgical exposure with decreased
access related complications, and improved outcomes can be attributed to increased user experience and comfort with percutaneous access, and this appears to be a viable first option. Thank you very much.
- Frank, thank you very much for your invitation. This is my disclosure. I think that all vascular surgeons are asking ourself following question. Is diameter of triple A the sole indicator for surgery? To ask for this question since about 20 years, we are interesting with function in aging with a PET CT
using 18F-FDG which allows the evaluation of the regional glucose metabolisms. And shows the presence of an inflammatory reaction at the level of atherosclerotic tissue infiltrated by the inflammatory cells. During our pilot study, we observed that
the uptake of the FDG was also stated with the unstable triple A. And during several studies, we were observed that FDG uptake not only show of predicted rupture but it predict also the site of the rupture
in triple A patients in Thoracic Aortic Aneurysms as well as Aortic Arch Aneurysm as you can see. Here is very easily we are find, you can observe FDG uptake and this patient we performed MRI and you can see here, free iron particles, it's same area of every velope. Starting increase FDG uptake
and this patient refused operation and come back three months later to rupture. Of course FDG is not specific for aneurysm or disease. We can found FDG uptake in cancer disease, infection or arthritis or arthritis and reason why several authors interested with different kind of biomarkers
and sodium fluoride F 18 each one of those one. And it's injections indicated for diagnostic PET imaging of bone to define areas of altered osteogenic activity. The primary clinical use of sodium fluoride PET is in detection of osseous prostate cancer metastasis. But some authors, all of them start to use it for
evaluation of the plaque metabolism in high cardiovascular risk subjects. One group from United Kingdom and leaded by a Dr. Newby from Cambridge, they performed several very nice studies using this marker in coronary artery disease for plaque rupture
and for evaluate aortic stenosis to accumulation of the calcification in the aortic leaflets. And also for carotid stenosis and they, during this several studies, they demonstrated that 18F sodium fluoride, selectively binds to microcalcification coronary
and carotid atherosclerotic plaques and that are associated with plaque vulnerability and rupture. More essentially he interested, they interest also the triple A and they called this study the SoFIA study and it concern about 72 cohort patients
and 20 study population. And it is very nice picture of the patients with positive 18F sodium fluoride uptake. It is specific for one and reason why it is left right in red color here, but anyways, very easy to show the infusion images uptake
at the symptomatic aneurysms. And they divided their cohort study in three levels of Tertile 1, Tertile 2, Tertile 3 according to sodium fluoride uptake from low uptake to increase uptake and they observed that the growth rate,
increased growth rate, aneurysm repair and rupture and aneurysm repair alone, it was significantly higher in the patients in Tertile 3 group. And they concluded that Fluorine-18 sodium PET-CT
is a novel and promising approach to the identification of disease activity in patients with triple A and is an additive predictor of aneurysm growth and future clinical events. My conclusion is 18F-FDG and 18F Sodium Fluoride however,
not specific for inflammation. Therefore, new imaging tracer for a more accurate inflammation detection and therapy evaluation are needed. We need specific markers of angiogenesis and inflammation to predict the triple A evolution and potential rupture.
Thank you very much for your attention.
- So I have the honor to provide you with the 12-month result of the TOBA II trial. I guess we all confirmed that this action is the primary mechanism of angioplasty. We all know that lesions of dissection have a TLR rate of 3.5 times higher than lesions without dissection.
The current tools for dissection repair, these are stents. They have limitations, really a large metal load left behind causing inflammation. This is leading to in-stent restenosis. So the Tack Endovascular System.
It's a delivery system over six French catheter. This is for above the knee with six implants pre-loaded on a single catheter. The Tack implant itself, it has an adaptive sizing, so it adapts to the diameter of the vessel from 2.6 up to 6.0 for SFA and PPA usage.
It's a nitinol implant with gold radiopaque markers for visibility. Has a unique anchoring system, which prevents migration, and a deck which is deployed in six millimeter in length. So with regard to the TOBA II study design,
this was a prospective multi-center single-arm non-blinded study at 33 sites in US and Europe. We enrolled 213 subjects. These were all subjects with post-PTA dissection. So only with a dissection visible on the angiogram, the patients could be enrolled into this study.
We had the usually primary safety end point, primary efficacy end points, which we are familiar from other trials and other studies so far. With regard to the inclusion criteria, I just want to look at this very briefly.
Mainly we had de novo or non-stented restenotic lesions in the SFA P1. If it was a stenosis, the lesion length could be up to 150 millimeter. If it was a total occlusion, the length was up to 10 centimeters.
They had to be the presence of at least one target run of vessel to the foot. They had to be a post residual, post-PTA residual stenosis of lower than 30%, and the presence of at least one dissection Grade A to F. With regard to the key lesion characteristics,
baseline for the different patients, there was not a big difference to other studies out there. The only difference was maybe we had slightly more patients with diabetes. The lesion, the target lesion length, the mean target lesion length was up to 74 millimeters.
We also had patients with calcification, mainly moderate but also some with severe calcification. There were two met the primary end points. The 30-day freedom from major adverse event, and also the primary efficacy end point at 12 months, which was a freedom from clinical driven TLR,
and freedom from core lab adjudicated duplex ultrasound derived binary restenosis. Now, with regard to patency in a patient cohort, where we really had 100% dissected vessel at 100% dissected vessel population, we had primary patency at 12-month of 79.3%
and a freedom clinical driven TLR of 86.5%. There was with regard to dissection severity, we had 369 total dissections we were treating. The number of dissections per subject was 1.8. The mean dissection length was two centimeters. So around 70% of subjects had a dissection of
Grade C or greater before using the Tack. In 92.1% of all dissections, this could be completely resolved with a Tack. With regard to the Tack stability and durability, in total, 871 Tacks have been deployed. So that was a number of 4.1 Tacks per subject.
The bailout stent rate was very low, just one. The freedom from Tack fracture at 12 months, 100%, and there was one minor Tack migration at 12 months with education by the core lab so the Tack was not seen at the same place as six months or 12 months before.
There was significant clinical improvement with Rutherford category improvement in 63%, which improved of up to two classes. There was also an improvement in ABI, walking impairment questionnaire. So just to conclude, TOBA II is a unique trial.
First to enroll 100% dissected vessels. Successfully met the primary efficacy and safety end points, and demonstrated the Tack is an efficient repair system for dissections after POBA or DCB with minimum metal left behind, low radial force, stable and durable design,
and preservation of future treatment options. There was only a very, very low bailout stent rate. This in combination with high patency rate and high freedom from clinical TLR. Thank you very much.
- Good afternoon. On behalf of my co-author Danielle Lyon I'd like to thank Dr. Veith for allowing us to present our data. No disclosures are relevant to this talk. So, why a small incision carotid endarterectomy? I actually came on to it maybe a decade ago when in debates for carotid stenting versus
carotid endarterectomy my interventional colleagues would show pictures like this. And pictures like this, with big incisions which is how I was trained from sternal notch to the angle of the mandible and above. Then I started thinking you know, maybe this could be done
through a smaller incision safely. So it's a smaller incision, it's cosmetically much more acceptable especially in ladies. Endarterectomy typically only involves about three centimeters of artery anyways. And, there's decreased tissue trauma
with a smaller incision. All of my patients are operated on clopidogrel and aspirin and we also operate on patients on full warfarin anticoagulation without reversal which we published in the annals a few years ago. So first, rely on the preoperative imaging.
So I always get a CTA to confirm the duplex ultrasound. Here you can see a very focal plaque in the proximal internal carotid artery. Here's a more heterogeneous plaque and opposite a carotid stint. I typically do these with,
under general anesthesia with EEG monitoring. The self-retaining retractor I use to stretch the incision would be, I think, a challenge in an awake patient. I image the carotid bifurcation, just like our previous speaker, with ultrasound ahead of time. Just a regular Site-Rite ultrasound,
you don't need a duplex. I typically call my friend Russell who comes with the ultrasound, and doing both longitudinal and transverse views to identify the carotid bifurcation and confirm the extent of the plaque. The incision is typically around three centimeters,
but clearly less than four centimeters, and it's centered over the previously marked carotid bifurcation. I use a standard incision along the anterior border of the sternomastoid muscle. And then use a self-retaining retractor to stretch the incision a bit.
This is a pediatric omni retractor which works really well for this purpose. It's very important, especially for the more-sef-full-ab blade to make sure that you identify the hypoglossal nerve as you can put a fair bit of traction on that upper blade and sometimes the incision is small enough that I actually
make a little counter incision for the proximal clamp. I've found that the use of a shunt can be challenging with this technique. There's one case out of 124 that I had to extend more proximally in order to safely put a shunt. I do, though, use acute ischemic preconditioning.
So typically the mean blood pressure is 90 or above, the patient's fully anticoagulated. I'll clamp the distal internal carotid artery and if there are EEG changes I'll unclamp it, raise the pressure just a little bit more and in most occasions the second or sometimes third time the internal
carotid artery is clamped the EEG does not change. And again, you can extend the incision if necessary as patient safety is absolutely paramount. So the technique is safe. In 124 consecutive patients there were no strokes or deaths.
There was one temporary cranial nerve injury which was the marginal mandibular. A complete endarterectomy can be achieved. Again, no increase in cranial nerve injury compared with a standard incision. And it really is a superior cosmetic result.
So here's a photo that I received from silk road, you probably did too. So here's the TCAR incision compared with a standard carotid endarterectomy incision on the other side. Here's a couple of my recent patients, so you can do this operation with an incision
that is about the same size as that utilized for TCAR. Thank you.
- Thank you Mr. Chairman. Ladies and gentleman, first of all, I would like to thank Dr. Veith for the honor of the podium. Fenestrated and branched stent graft are becoming a widespread use in the treatment of thoracoabdominal
and pararenal aortic aneurysms. Nevertheless, the risk of reinterventions during the follow-up of these procedures is not negligible. The Mayo Clinic group has recently proposed this classification for endoleaks
after FEVAR and BEVAR, that takes into account all the potential sources of aneurysm sac reperfusion after stent graft implant. If we look at the published data, the reported reintervention rate ranges between three and 25% of cases.
So this is still an open issue. We started our experience with fenestrated and branched stent grafts in January 2016, with 29 patients treated so far, for thoracoabdominal and pararenal/juxtarenal aortic aneurysms. We report an elective mortality rate of 7.7%.
That is significantly higher in urgent settings. We had two cases of transient paraparesis and both of them recovered, and two cases of complete paraplegia after urgent procedures, and both of them died. This is the surveillance protocol we applied
to the 25 patients that survived the first operation. As you can see here, we used to do a CT scan prior to discharge, and then again at three and 12 months after the intervention, and yearly thereafter, and according to our experience
there is no room for ultrasound examination in the follow-up of these procedures. We report five reinterventions according for 20% of cases. All of them were due to endoleaks and were fixed with bridging stent relining,
or embolization in case of type II, with no complications, no mortality. I'm going to show you a couple of cases from our series. A 66 years old man, a very complex surgical history. In 2005 he underwent open repair of descending thoracic aneurysm.
In 2009, a surgical debranching of visceral vessels followed by TEVAR for a type III thoracoabdominal aortic aneurysms. In 2016, the implant of a tube fenestrated stent-graft to fix a distal type I endoleak. And two years later the patient was readmitted
for a type II endoleak with aneurysm growth of more than one centimeter. This is the preoperative CT scan, and you see now the type II endoleak that comes from a left gastric artery that independently arises from the aneurysm sac.
This is the endoleak route that starts from a branch of the hepatic artery with retrograde flow into the left gastric artery, and then into the aneurysm sac. We approached this case from below through the fenestration for the SMA and the celiac trunk,
and here on the left side you see the superselective catheterization of the branch of the hepatic artery, and on the right side the microcatheter that has reached the nidus of the endoleak. We then embolized with onyx the endoleak
and the feeding vessel, and this is the nice final result in two different angiographic projections. Another case, a 76 years old man. In 2008, open repair for a AAA and right common iliac aneurysm.
Eight years later, the implant of a T-branch stent graft for a recurrent type IV thoracoabdominal aneurysm. And one year later, the patient was admitted again for a type IIIc endoleak, plus aneurysm of the left common iliac artery. This is the CT scan of this patient.
You will see here the endoleak at the level of the left renal branch here, and the aneurysm of the left common iliac just below the stent graft. We first treated the iliac aneurysm implanting an iliac branched device on the left side,
so preserving the left hypogastric artery. And in the same operation, from a bowl, we catheterized the left renal branch and fixed the endoleak that you see on the left side, with a total stent relining, with a nice final result on the right side.
And this is the CT scan follow-up one year after the reintervention. No endoleak at the level of the left renal branch, and nice exclusion of the left common iliac aneurysm. In conclusion, ladies and gentlemen, the risk of type I endoleak after FEVAR and BEVAR
is very low when the repair is planning with an adequate proximal sealing zone as we heard before from Professor Verhoeven. Much of reinterventions are due to type II and III endoleaks that can be treated by embolization or stent reinforcement. Last, but not least, the strict follow-up program
with CT scan is of paramount importance after these procedures. I thank you very much for your attention.
- 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 very much. After these beautiful two presentations a 4D ultrasound, it might look very old-fashioned to you. These are my disclosures. Last year, I presented on 4D ultrasound and the way how it can assess wall stress. Now, we know that from a biomechanical point,
it's clear that an aneurysm will rupture when the mechanical stress exceeds the local strength. So, it's important to know something about the state of the aortic wall, the mechanical properties and the stress that's all combined in the wall.
And that could be a better predictor for growth and potential rupture of the aneurysm. It has been performed peak wall stress analysis, using finite element analysis based on CT scan. Now, there has been a test looking at CT scans with and without rupture and given indication
what wall stress could predict in growth and rupture. Unfortunately, there has been no longitudinal studies to validate this system because of the limitations in radiation and nephrotoxic contrast. So, we thought that we could overcome these problems and building the possibilities for longitudinal studies
to do this similar assessment using ultrasound. As you can see here in this diagram in CT scan, mechanical properties and the wall thickness is fixed data based on the literature. Whereas with 3D ultrasound, you can get these mechanical properties from patient-specific imaging
that could give a more patient-specific mechanical AA model. We're still performing a longitudinal study. We started almost four years ago. We're following 320 patients, and every time when they come in surveillance, we perform a 3D ultrasound. I presented last year that we are able to,
with 3D ultrasound, we get adequate anatomy and the geometry is comparable to CT scan, and we get adequate wall stressors and mechanical parameters if we compare it with CT scan. Now, there are still some limitations in 3D ultrasound and that's the limited field of view and the cumbersome procedure and time-consuming procedures
to perform all the segmentation. So last year, we worked on increased field of view and automatic segmentation. As you can see, this is a single image where the aneurysm fits perfectly well in the field of view. But, when the aneurysm is larger, it will not fit
in a single view and you need multi-perspective imaging with multiple images that should be fused and so create one image in all. First, we perform the segmentation of the proximal and distal segment, and that's a segmentation algorithm that is
based on a well-established active deformable contour that was published in 1988 by Kass. Now, this is actually what we're doing. We're taking the proximal segment of the aneurysm. We're taking the distal segment. We perform the segmentation based on the algorithms,
and when we have the two images, we do a registration, sort of a merging of these imaging, first based on the central line. And then afterwards, there is an optimalisation of these images so that they finally perfectly fit on each other.
Once we've done that, we merge these data and we get the merged ultrasound data of a much larger field of view. And after that, we perform the final segmentation, as you can see here. By doing that, we have an increased field of view and we have an automatic segmentation system
that makes the procedure's analysis much and much less time-consuming. We validate it with CT scan and you can see that on the geometry, we have on the single assessment and the multi assessments, we have good similarity images. We also performed a verification on wall stress
and you can see that with these merged images, compared to CT scan, we get very good wall stress assessment compared to CT scan. Now, this is our view to the future. We believe that in a couple of years, we have all the algorithms aligned so that we can perform
a 3D ultrasound of the aorta, and we can see that based on the mechanical parameters that aneurysm is safe, or is maybe at risk, or as you see, when it's red, there is indication for surgery. This is where we want to go.
I give you a short sneak preview that we performed. We started the analysis of a longitudinal study and we're looking at if we could predict growth and rupture. As you can see on the left side, you see that we're looking at the wall stresses. There is no increase in wall stress in the patient
before the aneurysm ruptures. On the other side, there is a clear change in the stiffness of the aneurysm before it ruptures. So, it might be that wall stress is not a predictor for growth and rupture, but that mechanical parameters, like aneurysm stiffness, is a much better predictor.
But we hope to present on that more solid data next year. Thank you very much.
[Speaker] - Thank you very much and I appreciate the ability to present some of our research. First off, some of this was supported by AHRQ we're going to go through. What's important is, I think, Hyperglycemia is underestimated and It's been shown in general surgery to be a marker of poor clinical outcomes
in a variety of surgical patients. When you look at post-operative Hyperglycemia, it's been studied in general surgery and cardiac surgery. It's been associated with mortality and the surgical site infection. But there really is a limited amount of data
within the vascular information. So, in general, you look at the general surgery, majority of literature shows it has increased risk of infection, it has increased risk of a reoperative surgery, as well as increased risk of death. So we decided we would look at patients
undergoing lower extremity bypasses, open and Endo. And we found that in this study, one in five patients undergoing vascular procedures have hyperglycemia in their postoperative period. And, what was interesting is that diabetes was not an indicator for poor outcomes.
To do this we used the American Association of Endocrinology guidelines, which suggested optimal glucose would be between 80 and 180. Greater than 180 would be considered suboptimal. We then used Cerner information, which is EMR data. We divided the patients between open and endovascular
surgeries. We looked at our glucose targets and we looked at our outcomes. So I think what's most important is we looked at 4,000 patients. Mean years were 67 years in age. But what's more important to actually notice is that hyperglycemia was common,
more common in younger than old. It had an ethnic variability where African-Americans were likely to have hyperglycemia. But still, one in five patients after a lower extremity intervention, open or Endo, had hyperglycemia. So we're really not paying attention to it.
You can see that it occurred in equal percentages within open and endovascular surgery. And when you do a multi-vari logistic regression, we found that hyperglycemia, you had 1.3 times more likely risk of infection during your stay. You have a higher risk length of stay.
You had almost eight times greater risk of death. So, actually what's interesting is that diabetes was found to be productive, which suggests that it's really not diabetes, it's actually hyperglycemia is the main driver. As well, we found that certain medications will increase your hyperglycemia,as well as your disease severity.
We then move through this, we say that one in five patients have hyperglycemia. It's associated with increased lower extremity complications ,increased length of stay, as well as increased mortality. It was actually also unexpected that diabetes was not associated with inferior outcomes
and it's suggested it actually may be a marker with or without diabetic patients. We then looked at hyperglycemia in general surgery patients. We wanted to find out there was a risk in infection, as it's been shown. The general surgery population has thought
that maybe hyperglycemia is the most important risk factor for surgical site infection. We then looked at readmission of patients that underwent lower extremity bypass, to see why they were coming back. We found and infection at the index diagnosis was most significant for having a chance of readmission.
As well as anemia was highly also correlated with readmission. So, infection certainly is an important component to readmission. As well as Hyperglycemia is associated with readmission. It's important to remember that of the patients that come back for readmission after lower extremity procedures, almost half
of the lower extremity bypass procedures were associated with and infectious complication. And finally predictors of readmission, would include Hyperglycemia as it was associated with increased risk of infection at the index study. We then also wanted to see, other patients other studies
have looked to see if it can be controlled. This actually was a nice study, which is a perspective or analyzed study looking at insulin infusion protocol to improve outcomes. They show that surgical site infection was not reduced, they did well to look and see if they could control Hyperglycemia events
with an infrarenal bypass and open surgical repairs. And they used similar metrics for their Optimal Glycemic Control values. This study actually shows which is most interesting, that the most difficult patients to control were the patients with diabetes and the patients undergoing lower extremity bypass.
But they did show that by increasing glucose control, patients had lower rates of, lower lengths of stay. As well as had lower overall costs. So moving along we then looked at AAA. One in six patients who had undergone endovascular repair and open repair of AAA had hyperglycemia.
And we also did not find diabetes reported or predicted for outcome. We found that infections complications were significantly higher if you had postoperative hyperglycemia. Even in endovascular surgery 1.8 times is more likely. We also found diabetes not to be a factor.
So it's obviously more complex than diabetes. Once again mortality was also associated with hyperglycemia after open AAA and endovascular AAA. And we can see again that diabetes was not really playing a role. So AAA, increased mortality is associated with postoperative hyperglycemia.
If you have an EVAR it's 8 times more likely to have mortality. The diabetes was actually somewhat protective. And postoperative hyperglycemia is associated with infectious complications and increased length of stay. There's been suggestion hyperglycemia may be associated with stroke. We looked at this information,
we basically found that the crude rates of stroke were significantly greater for patients with hyperglycemia. We then did a regression analysis to evaluate. We found that stenting actually had a risk of stroke, but hyperglycemia as well also had a higher risk of stroke on this study. And once again diabetes
was not associated. So you can see after hyperglycemia with carotid studies, actually 1 in 7 after elective carotid procedures had hyperglycemia. And they were 8 times more likely to have mortality. 1 point times 7 more likely to have a stroke. So in conclusion, this study actually showed
that you can by involving glycemic control can be managed by using a management service. So you can be improved. This is by Goodney. In conclusion, hyperglycemia is a modifiable event. Postoperative hyperglycemia is very common in vascular surgery population. Between 1 in 5 after lower extremity to 1 in 7 after
elective carotid repair. That actually diabetes was not really the main associated or driver for hyperglycemia. We associate it with infection, length of stay and mortality. And regardless of etiology it can associate with mortality and inferior outcomes. Patients undergoing vascular surgery need
to have hyperglycemic management. And this evidence suggests this may decrease infections as well as complications and mortality. Thank you very much.
- Good morning, for all of you who got up early. It's a pleasure to be here, thank you Frank for the invitation. I'm going to talk about a problem that is extremely rare, and consequently can only be investigated by putting together databases from multiple institutions, called adventitial cystic disease.
Okay, I have no conflicts. So adventitial cystic disease is an extremely uncommon problem, but it's important because it occurs often in young people. Virtually all series of adventitial cystic disease have fewer than five patients in it,
so they essentially become case reports. And yet it's a very treatable problem. There are several theories about why it occurs, you can see this picture here. The mucin-assisting material that occurs in the popliteal artery region most commonly.
The etiology of that and the origin of that is debated, whether it comes from the joint space, whether it comes from rest, whatever. But it's not really known. In addition, what's not known is the best treatment. There are several options.
Some would advocate just simple aspiration of the cystic material, although it's very viscous. Others simply excising the cyst and leaving the vessel in place. Some both excising and either doing
an interposition graft or a bypass. Early results with every one of these options have been reported, but they're quite variable as far as the outcome. And therefore, we really don't know not only the optimal approach,
but also the best outcome. For that reason, we did a study with 13 institutions on adventitial cystic disease using a technique called vascular low-frequency disease consortium.
Where everybody uses a standardized database and similar collection to act like a single institution. The aim of this study, which is one of 20 that we've conducted over the last 15 years, was to determine first of all what people were doing
as far as current practice patterns, and then look at the outcomes with the different treatment options. And this was published in the Journal of Vascular Surgery. Adventitial cystic disease of any site was identified using both the CPT ICD-9 physician logbooks,
pathology databases, and procedure codes. And then we collected epidemiologic data as well as operative and follow-up data, with our primary endpoints being vessel patency and the need for re-intervention, since amputation is extremely uncommon and rare.
This is the process for the low-frequency disease consortium. Where not only is a standardized database used, but each institution collects their data after getting IRB approval. And then deidentifies it
before sending it to a central server. So there's no way that there could be a security breach. And then we do an analysis of the data. The results of this study were that in the small number of institutions, 15 institutions, 47 patients were identified.
The majority were male, and the majority were smokers. What was interesting to us was that not all are in the popliteal region. And actually there were several patients as you can see, who had upper-extremity adventitial cystic disease, although it's far more common in the popliteal space.
And also there was actually one patient who had adventitial cystic disease of the femoral vein. The symptoms were typically claudication, and ischemic rest pain or tissue loss were quite rare. If you look at the risk factors, smoking, which was probably a comorbidity
and would not be claimed to be the etiology but was present. Other than that, this is a typical distribution of patients with vascular disease. As far as imaging here, you can see a duplex ultrasound
showing the cystic mass and how it typically looks. The majority of patients had a duplex, but also they often had an MRA or CTA as well as an angiogram. And the angiogram was typically part of the treatment paradigm.
This is just the typical appearance of an MRA showing what some people would call the scimitar sign, which is that it's not a typical plaque. And this is a picture of a CT angiogram showing a similar view of a vessel. The results,
so there were some that did not treat only the cyst, but also resected the artery. And either bypassed it, as you can see here, or did an interposition graft,
here's just a picture of one of those. And there were others that just treated the cyst, and either aspirated it alone or resected the cyst and patched the artery. Or did cyst drainage and nothing else to the vessel. If you look at the typical incision of these patients,
this is a posterior approach of the popliteal region. And the small saphenous vein as you can see is marked, and uses the conduit for bypass. The outcomes of these patients were similar as far as length of stay, complications. The one you'll notice is that
two of the five with cyst resection had a complication, so that's a little bit higher. But otherwise they're quite similar as far as the short-term outcomes and results. The main problem, and also if we look at the improvement in ABI,
although cyst resection with bypass had a higher increase in ABI, the rest of the treatments were similar. In other words, the initial outcome was similar with any of those different options.
The one thing you can see circled in red is the patients who had simple cyst aspiration. It was not durable, and consequently they often had to have a second procedure. And the resection of the artery was generally, or bypass of the artery,
generally had better long-term outcomes. The follow-up was 20 months, and here you can see the recurrence and the types of modality of follow-up. So I just conclude by saying that our experience from multiple institutions
is that this is an uncommon problem, that cyst recurrence is very high if aspiration alone is used, and either interposition or bypass is the optimal treatment. Thanks very much for your attention.
- Thank you very much. So this is more or less a teaser. The outcome data will not be presented until next month. It's undergoing final analysis. So, the Vici Stent was the stent in the VIRTUS Trial. Self-expanding, Nitinol stent,
12, 14, and 16 in diameter, in three different lengths, and that's what was in the trial. It is a closed-cell stent, despite the fact that it's closed-cell, the flexibility is not as compromised. The deployment can be done from the distal end
or the proximal end for those who have any interest, if you're coming from the jugular or not in the direction of flow, or for whatever reason you want to deploy it from this end versus that end, those are possible in terms of the system. The trial design is not that different than the other three
now the differences, there are minor differences between the four trials that three completed, one soon to be complete, the definitions of the endpoints in terms of patency and major adverse events were very similar. The trial design as we talked about, the only thing
that is different in this study were the imaging requirements. Every patient got a venogram, an IVUS, and duplex at the insertion and it was required at the completion in one year also, the endpoint was venographic, and those who actually did get venograms,
they had the IVUS as well, so this is the only prospective study that will have that correlation of three different imagings before, after, and at follow-up. Classification, everybody's aware, PTS severity, everybody's aware, the endpoints, again as we talked about, are very similar to the others.
The primary patency in 12 months was define this freedom from occlusion by thrombosis or re-intervention. And the safety endpoints, again, very similar to everybody else. The baseline patient characteristics, this is the pivotal, as per design, there were 170 in the pivotal
and 30 in the feasibility study. The final outcome will be all mixed in, obviously. And this is the distribution of the patients. The important thing here is the severity of patients in this study. By design, all acute thrombotic patients, acute DVT patients
were excluded, so anybody who had history of DVT within three months were excluded in this patient. Therefore the patients were all either post-thrombotic, meaning true chronic rather than putting the acute patients in the post-thrombotic segment. And only 25% were Neville's.
That becomes important, so if you look at the four studies instead of an overview of the four, there were differences in those in terms on inclusion/exclusion criteria, although definitions were similar, and the main difference was the inclusion of the chronics, mostly chronics, in the VIRTUS study, the others allowed acute inclusion also.
Now in terms of definition of primary patency and comparison to the historical controls, there were minor differences in these trials in terms of what that historical control meant. However, the differences were only a few percentages. I just want to remind everyone to something we've always known
that the chronic post-thrombotics or chronic occlusions really do the worst, as opposed to Neville's and the acute thrombotics and this study, 25% were here, 75% were down here, these patients were not allowed. So when the results are known, and out, and analyzed it's important not to put them in terms of percentage
for the entire cohort, all trials need to report all of these three categories separately. So in conclusion venous anatomy and disease requires obviously dedicated stent. The VIRTUS feasibility included 30 with 170 patients in the pivotal cohort, the 12 months data will be available
in about a month, 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.
- Good morning, I would like to thank Dr. Veith, and the co-chairs for inviting me to talk. I have nothing to disclose. Some background on this information, patients with Inflammatory Bowel Disease are at least three times more likely to suffer a thrombo-embolic event, when compared to the general population.
The incidence is 0.1 - 0.5% per year. Overall mortality associated with these events can be as high as 25%, and postmortem exams reveal an incidence of 39-41% indicating that systemic thrombo-embolism is probably underdiagnosed. Thrombosis mainly occurs during disease exacerbation,
however proctocolectomy has not been shown to be preventative. Etiology behind this is not well known, but it's thought to be multifactorial. Including decrease in fibrinolytic activity, increase in platelet activation,
defects in the protein C pathway. Dyslipidemia and long term inflammation also puts patients at risk for an increase in atherosclerosis. In addition, these patients lack vitamins, are often dehydrated, anemic, and at times immobilized. Traditionally, the venous thrombosis is thought
to be more common, however recent retrospective review of the Health Care Utilization Project nationwide inpatient sample database, reported not only an increase in the incidence but that arterial complications may happen more frequently than venous.
I was going to present four patients over the course of one year, that were treated at my institution. The first patient is 25 year old female with Crohn's disease, who had a transverse colectomy one year prior to presentation. Presented with right flank pain, she was found to have
right sided PE, a right sided pulmonary vein thrombosis and a left atrial thrombosis. She was admitted for IV heparin, four days later she had developed abdominal pains, underwent an abdominal CTA significant for SMA occlusion prompting an SMA thrombectomy.
This is a picture of her CAT scan showing the right PE, the right pulmonary vein thrombosis extending into the left atrium. The SMA defect. She returned to the OR for second and third looks, underwent a subtotal colectomy,
small bowel resection with end ileostomy during the third operation. She had her heparin held post-operatively due to significant post-op bleeding, and over the next three to five days she got significantly worse, developed progressive fevers increase found to have
SMA re-thrombosis, which you can see here on her CAT scan. She ended up going back to the operating room and having the majority of her small bowel removed, and went on to be transferred to an outside facility for bowel transplant. Our second patient is a 59 year old female who presented
five days a recent flare of ulcerative colitis. She presented with right lower extremity pain and numbness times one day. She was found to have acute limb ischemia, category three. An attempt was made at open revascularization with thrombectomy, however the pedal vessels were occluded.
The leg was significantly ischemic and flow could not be re-established despite multiple attempts at cut-downs at different levels. You can see her angiogram here at the end of the case. She subsequently went on to have a below knee amputation, and her hospital course was complicated by
a colonic perforation due to the colitis not responding to conservative measures. She underwent a subtotal colectomy and end ileostomy. Just in the interest of time we'll skip past the second, third, and fourth patients here. These patients represent catastrophic complications of
atypical thrombo-embolic events occurring in IBD flares. Patients with inflammatory disease are at an increased risk for both arterial and venous thrombotic complications. So the questions to be answered: are the current recommendations adequate? Currently heparin prophylaxis is recommended for
inpatients hospitalized for severe disease. And, if this is not adequate, what treatments should we recommend, the medication choice, and the duration of treatment? These arterial and venous complications occurring in the visceral and peripheral arteries
are likely underappreciated clinically as a risk for patients with IBD flares and they demonstrate a need to look at further indications for thrombo-prophylaxis. Thank you.
- Thank you. No relevant disclosures to this presentation. The means to the end is removing Uremic toxins. That's what we want to do. That's what this is all about. We don't really know all the Uremic toxins and how they inter-relate, but there are a bunch
of compounds that have been identified. Urea obviously being one of them, although not necessarily being a particularly toxic compound. It's a small molecular weight marker of Uremia, which is convenient to use
if not clinically meaningful. We've developed, or Frank Gotch and Sargent developed this dimensionless concept of the Kt/V, an index of the body volume water space, which has been cleared fully of Urea and this index has been the standard for comparing dosing of dialysis for about 30 years now.
Since the National Cooperative Dialysis Study in the 80's. And the most recent iteration of this study has been the HEMO study in 2002, I believe this was published. Where they compared a high dose of Kt/V of 1.71 versus standard dose Kt/V of 1.3 and looked at patient outcomes and they were
concluding that the higher dose of dialysis wasn't beneficial. But this 1.3 was certainly better than we were seeing in the old days of 0.9 out of the NKDS studies, so 1.3 or that range has been accepted as the target dose
for dialysis and KDOQI guidelines now suggest that we strive to achieve a single pool Kt/V of 1.4, so we have a little cushion with a minimum delivery of 1.2, and that has been adopted now by CMS and the payers.
That's in our conditions for coverage that we achieve or we strive for a Kt/V 1.2 and now we have this quality incentive program, which might relate a little bit to the question earlier about saving access as we get penalized or incentivized
for doing certain things, and right in our penalty methodology in the top categories Kt/V, if we don't hit that target we get dinged up to 2% of the total payment for dialysis on that.
So it's something that's being identified, monitored, and if you like ... Not negatively incentivized. It's not a reward. It's a penalty for failing to achieve. And also you can go to dialysiscompare.gov now.
You login your unit. Here's my little unit in Hockessin. We got four stars. A nearby unit got three stars. They're really just as good as us, but somebody thinks those stars mean something,
and one of the components in those stars is hitting your Kt/V target, so if I want to get stars and not be seen as a poor performing unit, I need to hit these performance parameters, so that's why the Kt/V is the holy grail for Nephrologist. We need to get that number.
It's a very simple concept. Mathematically, you've got two items in the numerator and one in the denominator, and you want to maximize that parameter. Number one we can dispense with the volume of distribution
of Urea is pretty much determined by the patient. It's total body of water times the fraction. It varies a lot depending on the age, weight, gender, obesity, etc. You can put it in the calculator and same qx metal to deliver that number for you.
But we can't really change that, unless somebody has an amputation, or a large amount of weight loss or gain, then it changes. Time we have complete control over. We can dialyze theoretically as long as we want and in the U.S. we sort of like
to believe four hours has been adopted as a standard. There are some recommendations that wouldn't do that. Patient acceptance of that is variable. I can sit in front of a patient and tell them they need four and half hours, and they may look at me askance,
because they know they don't want it, and if you look at dialysis times in different countries, you can see certain countries like Germany, typically dialyzes closer to three hours. Typical dialysis time in the United States is more like... Did I say three hours?
I meant five hours. And typical dialysis time in the United States is about three and a half hours. There are also resource limitations and cost involved in that. So the third variable is the one we have
the most control over, which is the clearance of Urea. And that's depending on the dialyze of the blood, in the blood, out. the dialyze of that... capacity of that filter to remove the solute of interest, Urea in this case in a dialysate flow,
and there are specs for each kidney. Here is a Optiflux F160 at a blood flow of 300 and a dialysate flow of 500. It predicts we should get a Urea clearance of 271 mL per minute, or conversely a larger kidney, an F180 had a blood flow of 500, a dialysate flow of 800.
We should get a Urea clearance of 412. Obviously, none of these are perfect clearances. The maximum theoretical clearance would be that of the blood speed, but it's impossible to clear it 100% of the blood. So when your asked as a surgeon or a provincialist
to make a functional access what your Nephrologist is really asking for in a customer service world is give me a fistula that flows 150% higher. 150% of my intended pump speed and we're good to go. Need a little cushion on that as well.
And here's how it translates into action. Here's an example on a calculator. Here's a patient, who's a 70 kilogram female, dialysis time three and a half hours, 210 minutes. Her Kt/V calculates at 1.77. All good.
Same parameters three and a half hours, 120 kilogram, 40 year old male. His Kt/V is 0.96, clearly below the target. You're not going to get that guy's clearance with those parameters. If you goose him up to 500 mL per minute
on a minute on a bigger kidney and you achieve a clearance of 410, then the same male with the same treatment parameters will get 1.45, so you've met their target. If you want to do better than targets just put him on four hours and you only get 1.66,
so these are very easily definable, measurable, predictable quantities that you can achieve. And then you've got limiting factors. What is the pump speed? Well, hemolysis through needles is really an overstated concern.
This arterial negative pressure alarm won't let you go below 250 on this machine and if-- 300 is it Debbie? 250, 300 and at that point it will cut off, so you won't be able to drive the negative pressure that high,
and so you've got parameters for each needle, which are fairly fixed, a little latitude in it, but with 17-gauge needle you can go up to 300 and so on. With a 14-gauge needle you can go up to 500 or more, and it's a pretty si le higher flow.
And here's a case where you've got a 2 millimeter radial artery, a small fistula. The access flow measures at 450. You can dialyze at a blood speed of 300 with a 17-gauge needle and you're good to go. Where as you got a huge brachial artery here.
This access flow is greater than 2000. You can run the blood speed at whatever you want. And you can use a needle size of 14-gauge. You can put whatever needle size you want in this fistula. So the point is that one size doesn't fit all. Dialysis dose, and dialysis needles,
and dialysis fistulas need to be scaled to the size of the patient. You got a neonate. You got Shaquille O'Neal. Somewhere in between is our patient. Thank you.
- Thank you Dr. Asher. What an honor it is to be up here with Dr. Veith and Dr. Asher towards the end. You guys are leading by example being at the end of the meetings. So, thank you for allowing me to be up and talking about something
that not a lot of vascular surgeons have experience with, including me. I have no disclosures. On your left, I have listed some of the types of diseases that we most commonly see in the vertebral artery, and there are quite a lot.
And on the right, the standard types of treatment that we pursue in vascular surgery or as a vascular specialist. And often, in the vertebral artery, if we are going to pursue treatment, it's the endovascular route.
But I'll talk a little bit about open surgery. The clinical presentation is often vague. And the things I wanted to point out here in this long list are things like alternating paresthesias, dysphagia, or perioral numbness may be something in the history to look for
that you may not be thinking about when you're thinking about vertebral basilar disease. The anatomy looks straightforward in this picture, with the four segments, as you can see. It gets a little more complicated with just the arterial system,
but then when you start looking at all these structures, that you have to get out of of the way to get to the vertebral artery, it actually can be a difficult operation, particularly even in the V1 segment. The V1 typically is atherosclerotic disease.
V2 is often compression, via osteophyte or musculo-tendon structures. And V3 and V4, at the top, are typically from a dissection injury from sort of stretch or trauma injury. The pathophysiology isn't that well understood.
You have varying anatomy. It's very difficult to access this artery. Symptoms can be difficult to read, and treatment outcomes are not as reliable. But I'm going to take you through a very quick path through history here in the description
of the V1 segment exposure by Dr. Rentschler from 1958. And I love these pictures. Here is a transverse incision over the sternocleidomastoid, just above the clavicular head on the right side. And once you get the sternoclavicular head divided, you can see the longus colli muscle there.
Anteromedial is the carotid. Of course, you surround that with a Penrose drain. And then once you do that, you can separate your longus colli, and deep to that, the vertebral artery just easily slips right up, so you can do your transposition.
It's not quite that easy. I've done one of these operations, and it was difficult finding t e. And, again, here is on the opposite side, you can see the transposition in this cartoon.
Dr. Berguer is the world's expert, and a lot of this open surgical work comes out of the University of Michigan. Here is a study looking at 369 consecutive extracranial vertebral artery reconstructions. You can see the demographics of clinical presentation.
And note that about 34% of patients are presenting with hemispheric symptoms, with 60% in the vertebral basilar distribution. 300 of these reconstructions were for atherosclerosis. And the outcomes were pretty good. Before 1991, there wasn't really a protocol in place
in assessing and doing these procedures. And you can see the stroke and death rates of 4.1 and 3.2% respectively. And then the outcomes after 1991 are considerably better with a five year patency rate of 80%. So, in summary, vertebral artery disease is,
I think if you review this, is somewhat under diagnosed. Revascularization is a viable option. Most often, it's endovascular. But if you have endo-hostility, then an open, particularly for the V1 segment, may be a better option.
And this requires people with good operative experience. 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.
- Lymphatic, so it's fun, actually, not to talk on venous interventions for once. And, naturally, the two systems are very different. But, on the other hand, they're also related in several ways and I will come back to that later. I have no disclosures, maybe only my gratitude to this man, Dr. Maxim Itkin,
who actually got me started in the field, and was gracious enough to supply me some of his material. And who is also responsible for making our lives way easier over the last years. Because in former times, we needed to do, to visualize the lymphatic system,
we needed to do pedal lymphangiography and that was very, very cumbersome. It took a long time and was very painful for the patient. And he introduced the ultrasound guided intranodal lymphangiography,
and that's fairly easy for most of us. With ultrasound you find a lymph node in the groin, you puncture that and you can control the needle position with contrast enhanced ultrasound and once you establish that position, you might do a MR lymphangiography.
Thereby showing, in this case, a beautiful, normal anatomy of the thoracic duct. I need to say, the variations in lymphatics are extreme. So, you can also visualize, naturally, the pathology, like for example, pulmonary lymphatic perfusion syndrome.
What's going on there. Normally, lymph courses up through thoracic duct, but in this case, you kind of have a reflux in the bronchial tree and lymph leakage. And you can image that again, beautifully with MR, which you can show extensive leakage
of lymph in the lung parenchyma. So you can treat that. How can you treat that? By embolization of the thoracic duct. But first we need to get into there, and that's not a very easy thing to do.
But now, again, with access to a lymph node in the groin, you can push lipiodol, and then visualize the cisterna chyli and access that transcutaneously with a 21/22 gauge needle and then push up a O-18 wire high up in the thoracic duct.
First you deploy some coils to prevent any leakage of glue inside the venous system, and then by microcatheter, you infuse glue all the way down, embolizing the thoracic duct. So, complete different group of lymphatic disorders is oriented in the liver and hepatic lymphatic disorders.
And maybe not everybody knows that, but 80% of the flow in the thoracic duct is caused by the liver and by the intestine. And many times in lymphatic disorders, there needs to be a combination of two factors. One factor is a venous variation of a,
sorry, an anatomical variation in lymph vessels and the other one is that we have an increase in lymph flow. And in the liver, that can be caused by a congestion of the liver, for example, cirrhosis, or a right side, that's congested heart failure.
What happens then is you increase the flow, the lymph flow, tremendously and if you also have a variation like in this case, when the vessels do not directly course towards the cisterna chyli, but in very close contact to the abdomen,
then you can have leakage of the lymph and leakage of proteins, which is a serious problem. So, what is then, to do next? You can access the lymph vessels in the liver by percutaneous access in the periportal space,
and induce some contrast and then later, visualize that one back, visualize that with dye that you can see with an endoscopy, thereby proving your diagnosis, and then, in a similar way,
you can induce lipiodol again with glue, embolizing the lymph vessels in the liver, treating the problem. In summary, popularity of lymphatic interventions really increased over the last years mainly because novel imaging,
novel interventional techniques, new approaches, and we all gained more experience. If you would like, I would guess that, we are at a phase where we were at venous, like 10, 15 years ago. If we are a little bit positive,
then the future is very bright. And within 10, 15 years, we find new indications and probably have much more to tell you. Thank you for your attention.
- This is a little bit more detailed explanation of the pathophysiology behind Type IV AVM's. Medical disclosures are none. And this is the Yakes classification and this is Type IV lesion we are going to talk about now. So, this angioarchitecture has not been described before, and was first described in the Yakes classification.
What is so unique? It has multiple arteries, arterioles, but these arterioles form innumerable fistulas that are of a microsize, and they infiltrate the affected tissue. So, this is, this can affect every kind of tissue,
skin involvement and muscle involvement, and other than brain AVM, bleeding occurs if mucosa involvement is present or if an ulcer is present. So, we have to think about the definition of an AVM, which is an artery to vein connection
without an intervening capillary bed. But, what applies in Type IV? As you can see here, very nice example of this infiltrating type is that the tissue where the AVM is located is also viable, so the assumption is that
normal capillary beds are interspersed into these innumerable AVMs existing next to the malformed AVM fistulas, and this is a new definition of AVM. So, how to access this lesion? Of course, transarterial is possible
with a catheter or micro catheter. If anatomy doesn't allow transarterial approach, direct puncture is an option. Also, as you can see, in the direct puncture in the lower video, you can see the venus drainage of these fistulas,
and direct puncture of the vein compressed to reflux ethanol into the fistulas is also an approach. But, what is the challenge here? If you want to treat this lesion, you have to keep in mind
that you don't want to occlude the capillaries that are supplying the tissue. So, to find the right treatment approach, the physiologic concept is often important to understand that the arteriovenous fistulas drain into multiple veins and arterialize these veins
so we have a high pressure on this venus outflow site. The normal capillaries have a normal outflow too but this is of lower pressure, and this comes to competition between the arterialized veins and the normal venus outflow, which is, which is inferior to the normal capillary outflow.
So, what follows is a restriction of normal tissue flow with back-up to the capillaries, and backing up into the arterial inflow. So, we have the situation that the arterial venus fistulas have a lower pressure, lower resistance, and an increased arterial flow
compared to the normal capillaries, and this has to be taken into advantage for treatment. How can this be achieved? Thicken the fluid and dilute the ethanol by creating a mixture of 50/50 contrast and ethanol. So, this mixture will follow the preferential flow
into the arteriovenous fistulas in transarterial injections bearing the normal capillaries. So, if it's possible to puncture into the fistulas, pure ethanol can be used, but especially in transarterial access where normal nutrient vessels can be filled,
50:50 mixture contrast is the key to treat a Type IV AVM, Type IV Yates AVM, and here, you can see, using this approach, how this AVM can partly be treated in many several treatment sessions. And here you can see the clinical result. So, this huge ulcer, after seven treatments, healed
because of the less venus hypertension in the lesion. So the additional benefit of 50/50% ethanol contrast mixture is that your injection is visible on flouroscopy so you can see if which vessels you are including. You can react and adjust the pressure you're injecting. So, it also has to be considered
that the more you give diluted, the more total ethanol can be needed, but it's not efficient in larger vessels. This is also the advantage that you just treat the microfistulas. It's of importance that you use non-ionic contrast
as ionic contrast precipitates in the mixture. So here, you can see again, see the Type IV AVM of the arm and hand, which I already showed in my first talk, and here, you see the cured result after multiple sessions showing good arterial drum without fistulas remaining.
So, the conclusion is that Yakes Type IV is a new entity. It's crucial to understand the hemodynamics and the concept of 50/50 contrast ethanol mixture to treat this lesion with also a curative approach. Thank you very much.
- Thank you. Here are my disclosures. Our preferred method for zone one TAVR has evolved to a carotid/carotid transposition and left subclavian retro-sandwich. The technique begins with a low transverse collar incision. The incision is deepened through the platysma
and subplatysmal flaps are then elevated. The dissection is continued along the anterior border of the sternocleidomastoid entering the carotid sheath anteromedial to the jugular vein. The common carotid artery is exposed
and controlled with a vessel loop. (mumbling) The exposure's repeated for the left common carotid artery and extended as far proximal to the omohyoid muscle as possible. A retropharyngeal plane is created using blunt dissection
along the anterior border of the cervical vertebra. A tunneling clamp is then utilized to preserve the plane with umbilical tape. Additional vessel loops are placed in the distal and mid right common carotid artery and the patient is systemically anticoagulated.
The proximal and distal vessel loops are tightened and a transverse arteriotomy is created between the middle and distal vessel loops. A flexible shunt is inserted and initially secured with the proximal and middle vessel loops. (whistling)
It is then advanced beyond the proximal vessel loop and secured into that position. The left common carotid artery is then clamped proximally and distally, suture ligated, clipped and then transected. (mumbling)
The proximal end is then brought through the retropharyngeal tunnel. - [Surgeon] It's found to have (mumbles). - An end-to-side carotid anastomosis is then created between the proximal and middle vessel loops. If preferred the right carotid arteriotomy
can be made ovoid with scissors or a punch to provide a better shape match with the recipient vessel. The complete anastomosis is back-bled and carefully flushed out the distal right carotid arteriotomy.
Flow is then restored to the left carotid artery, I mean to the right carotid artery or to the left carotid artery by tightening the middle vessel loop and loosening the proximal vessel loop. The shunt can then be removed
and the right common carotid artery safely clamped distal to the transposition. The distal arteriotomy is then closed in standard fashion and flow is restored to the right common carotid artery. This technique avoids a prosthetic graft
and the retropharyngeal space while maintaining flow in at least one carotid system at all times. Once, and here's a view of the vessels, once hemostasis is assured the platysma is reapproximated with a running suture followed by a subcuticular stitch
for an excellent cosmetic result. Our preferred method for left subclavian preservation is the retro-sandwich technique which involves deploying an initial endograft just distal to the left subclavian followed by both proximal aortic extension
and a left subclavian covered stent in parallel fashion. We prefer this configuration because it provides a second source of cerebral blood flow independent of the innominate artery
and maintains ready access to the renovisceral vessels if further aortic intervention is required in the future. Thank you.
- [Sergio] Good morning everybody. I really do thank you for the opportunity to reason with you about the lower limbs venous kinetics and the consequent impact on drainage direction. I have no conflicts of interest to declare, particularly because this talk is all about physics and about those laws of physics
that rule the venous drainage. We could say that the drainage occurs along our Italian leg, along a deep venous highway, a saphenous freeway and along several tributary and perforated roads.
But we could also say that we could divide the anatomy of our lower limb into three different compartments. So the tributary one's above the fascia, the saphenous one in between the fascia layers, and the deep venous one below the fascia. In this kind of network, talking about physics,
we could apply the Bernoulli's principle which, to make it simple, states that whenever there is an acceleration, a lateral pressure drop occurs. Which introduces the Venturi's effect as a potential aspiration of blood
from a slowest toward a fastest vessel. But actually, up to now, we couldn't say this for sure and say that venous network because we have really few data on the literature about the velocity values that we have in the different segments of the different compartments.
So the aim of this investigation, in the first physiological part, was to evaluate the different velocity values of different segments, understanding if the Venturi's effect could be applied inside this network, and then looking at the pathological cases.
So we have 36 lower limbs of healthy controls, and we assess all the velocity segments in the different segments of the three different compartments, evoking the flow both by active dorsal flection maneuvers of the foot, and by compression/relaxation
of the calf of course. So we compared all the different values of all the different velocities with the two different maneuvers, and we created several tables and we performed several statistical tests to see
how these velocities were behaving in the different compartments. So it's pretty interesting to notice that there are segments of our venous networks in which if we are performing the vocation of the flow with two different maneuvers, we are going to have
significantly different values of velocity. So for example, this happened in the external iliac vein, in the femoral vein, in the posterior tibial vein, and the tributary veins. If you look at the graph, we realize that there is a gradient of velocities
that is decreasing in physiology. While we are moving from the deepest, toward the most superficial compartment. And if we take all these velocities we assess together, we see that there are three different groups of velocities basically, statistically speaking,
that almost totally overlap the anatomical compartments, with some exception. So if you look over here for example, you have the posterior tibial vein that belongs to the deep venous system of course, in terms of anatomy, but not in terms of velocities.
Which means that the velocity we reported were significantly different from the ones belonging to the deep venous compartment. The same thing for the short saphenous vein, which demonstrated to of course belong to the saphenous compartment in terms of anatomy
but not in terms of velocities. If we move toward the pathological part of this, and we look at the 40 chronic venous disease patients we assessed in a model in which we considered incompetent tributary as the segment you see over there, depicted as C.
Compared to the adjacent GSV trunk, A and B. It's interesting to notice how the peak diastolic velocity and the diastolic time average velocity are actually significantly higher in the tributary compared to the GSV in pathological cases.
And if we look at the resistance index, it's interesting to notice how the segment in B, so the GSV trunk below the confluence, is actually higher. Like indicating a sort of preferential road of drainage toward the incompetent tributary.
This introduced the Venturi's effect, so now we can see the Venturi's effect could play a role inside the venous network. In physiology with a gradient that is increasing in terms of velocity, so potential aspiration while we are going toward the deepest compartment.
And the gradient that is subverted in pathology, where we have tributaries that are going faster when they are incompetent, compared to the GSV trunk, so leading to potential aspiration. But our blood is not a newtonian fluid, our vessels are not ideal conduits,
so we have to admit some things we know that we know, and that's of course the newtonian physics. Kn we know that we don't know,
and that's the application of the newtonian physics inside the human body. And then unkn things we don't even know that we don't know. That's the in-vivo validation
of these physical models. Independently by what we know and by what we don't know, I totally agree with profe tters and starting from today we know that Venturi's effect could play a role inside the venous network. Thank you.
- This is in line with the earlier discussions we have had regarding cannulation and things. I don't have any disclosure with this. Now, Doctor Sher gave me this topic about cannulation mapping, how does it help dialysis staff? I thought I'd probably try to dissect this a little bit by giving a short introduction and try to define
what I'm talking about and try to look into a little bit about who uses this, who cannulates, and what are the critical components required to make the cannulation safe, so on and so forth. And I'll summarize what I am talking about. As we know, for having successful dialysis we need
about 350 to 450 mls of blood going to the machine and this is drawn by putting two needles in a subcutaneous conduit which has got high blood flow, maybe a graft or a fistula. And it requires two needles to get in there, one to pull the blood out to the machine
and second one to push the blood back. So what is cannulation? One can probably say cannulation is the act of insertion of a needle into a vessel to allow blood to be successfully drawn out by the dialyzer pump and returned to the blood vessel.
Who cannulates? Generally if you look in American practice we are talking about technicians cannulating, and technicians, til recently, the basic qualification required to apply for this job was high school diploma. Nowadays some of the units look for MA's and CNA trainings
that that way they have some medical background. But most of the training for cannulation happens on site by senior people who are there and that's the only training people get. Many of the people do not have medical background. So what do they cannulate?
We create all sorts of access. When you talk about fistula we have fistula which are deep, we have fistula which are coiled, we have fistula which are kind of short, we have a fistula long, in the armpit, all over the place. Then we have grafts in our patients.
When they get into problems we try to do all sort of exotic graft like chest wall graft, necklace graft, forearm, upper arm graft, multiple scars. Now obviously, for someone who is got minimum training, doesn't have much medical background, we have to have some sort of a guidance
and that is cannulation mapping. What is cannulation mapping? It is any guidance to facilitate reliable cannulation. And if you think of in terms of guidance we can do it in two ways. One is we can mark and document and communicate.
The other thing is realtime guidance. Realtime guidance can be off site or can be on site. So marking probably should include nature of the conduit. Are you cannulating a graft or a fistula? Those are two different ways of cannulation, 100% different material.
You also need to talk about what are the direction of blood flow. What are the cannulation segments? Where do you cannulate and how deep is the vessel because depth of the vessel determines what angle you use for cannulation,
to be on the safer side. And these instructions should be given to the people who are cannulating. And how do we collect this data? Most of us have access to ultrasound if not we have a lab nearby which has an ultrasound.
Ultrasound can pretty much look into all the parameters including the flow, direction of flow, depth of the vein, size of the vein, cannulation segment, and everything else. We could document it and we could come with form. This is the form I use before sending any
of my patient to dialysis unit before they start cannulating. And this has all the information required for the nurses. We do that. We draw the cannula, we draw the outflow vein pattern, or cannulation segment pattern, and I confirm it
with ultrasound to make sure that if I can draw without using an ultrasound somebody else should be able to find it by clinical exam and I confirm my drawing is right. That way there's no confusion. We draw it on the paper if need be,
send it with the patient. Most of our patients do have cell phones now. We make the patients take the picture with their own cell phone that way they have that documented because this marking is going to go away. And for the marking to stay there for some time
we cover it up with some transparent tegaderm or some sort of a dressing that way when they go to the dialysis they have the marking. They're going with the sheet, with the instruction how to cannulate, where to cannulate, what is the direction of the vein,
how deep it is, maybe you should not use much of an angle, try to keep the needle flat to the skin, so on and so forth. Now, can we do it real time? Real time can be done off site. I have my pediatric nurses who come to my office all the time with the kids
when the first time when I can. I show them with the ultrasound. Any time a cannulator comes to your office and looks with ultrasound, believe me, their whole impression of what is under the skin becomes clearer
because ultrasound shows you what exactly is under the skin there. So, it is a good way of doing it, little bit shy of being real time in the unit. So they can come to you and when they see such things, you try to have results like this.
Here's a button hole which is created not on top of the vein because it's very superficial and you may cannulate, you may infiltrate, but it's created on the side of the vein. And that is only because they had a mental conception of how to do this button hole, or train the button hole,
and it's working pretty well for a long period of time. Now, real time cannulation can be done in the units. There are lot of articles out there giving you how to do it, how to image a vessel, and how to put the needle in. And some people have started writing about it
because many of the units have acquired ultrasounds. Obviously it's kind of based on who's running the unit. And this is not a routine or a norm because most of the companies they don't have funding to get the unit. But you know I was talking to you about being in Japan. When you go to their unit they do have
hand held ultrasound machines and they do categorize their patients as patients who are easy to cannulate, patients who are in between, and patients who are difficult to cannulate. Patients who are difficult to cannulate do use ultrasound for cannulation.
They hardly ever superficialize their vessels. So there are real advantages for using an ultrasound real time. Now, obviously the disadvantage becomes costs associated with it, but I feel a cost saving done by ultrasound by preventing infiltrations,
infiltration related hospitalization, loss of access, need for catheters, so on and so forth by far supersedes the cost in ward in getting one or using one. So just to summarize. Morphology of the access can be very varied.
Existing training pathways for cannulation personnel is inadequate to produce expert cannulators. Any cannulation mapping is valuable to increase cannulation safety and the patient's comfort. Ultrasound is an excellent tool for cannulation mapping. Real time ultrasound is useful
to provide cannulation guidelines and availability of real time ultrasound in dialysis unit is cost saving measure that could significantly impact patient safety and satisfaction. Thank you.
- So my charge is to talk about using band for steal. I have no relevant disclosures. We're all familiar with steal. The upper extremity particularly is able to accommodate for the short circuit that a access is with up to a 20 fold increase in flow. The problem is that the distal bed
is not necessarily as able to accommodate for that and that's where steal comes in. 10 to 20% of patients have some degree of steal if you ask them carefully. About 4% have it bad enough to require an intervention. Dialysis associated steal syndrome
is more prevalent in diabetics, connective tissue disease patients, patients with PVD, small vessels particularly, and females seem to be predisposed to this. The distal brachial artery as the inflow source seems to be the highest risk location. You see steal more commonly early with graft placement
and later with fistulas, and finally if you get it on one side you're very likely to get it on the other side. The symptoms that we are looking for are coldness, numbness, pain, at the hand, the digital level particularly, weakness in hand claudication, digital ulceration, and then finally gangrene in advanced cases.
So when you have this kind of a picture it's not too subtle. You know what's going on. However, it is difficult sometimes to differentiate steal from neuropathy and there is some interaction between the two.
We look for a relationship to blood pressure. If people get symptomatic when their blood pressure's low or when they're on the access circuit, that is more with steal. If it's following a dermatomal pattern that may be a median neuropathy
which we find to be pretty common in these patients. Diagnostic tests, digital pressures and pulse volume recordings are probably the best we have to assess this. Unfortunately the digital pressures are not, they're very sensitive but not very specific. There are a lot of patients with low digital pressures
that have no symptoms, and we think that a pressure less than 60 is probably consistent, or a digital brachial index of somewhere between .45 and .6. But again, specificity is poor. We think the digital pulse volume recordings is probably the most useful.
As you can see in this patient there's quite a difference in digital waveforms from one side to the other, and more importantly we like to see augmentation of that waveform with fistula compression not only diagnostically but also that is predictive of the benefit you'll get with treatment.
So what are our treatment options? Well, we have ligation. We have banding. We have the distal revascularization interval ligation, or DRIL, procedure. We have RUDI, revision using distal inflow,
and we have proximalization of arterial inflow as the approaches that have been used. Ligation is a, basically it restores baseline anatomy. It's a very simple procedure, but of course it abandons the access and many of these patients don't have a lot of good alternatives.
So it's not a great choice, but sometimes a necessary choice. This picture shows banding as we perform it, usually narrowing the anastomosis near the artery. It restricts flow so you preserve the fistula but with lower flows.
It's also simple and not very morbid to do. It's got a less predictable effect. This is a dynamic process, and so knowing exactly how tightly to band this and whether that's going to be enough is not always clear. This is not a good choice for low flow fistula,
'cause again, you are restricting flow. For the same reason, it's probably not a great choice for prosthetic fistulas which require more flow. So, the DRIL procedure most people are familiar with. It involves a proximalization of your inflow to five to 10 centimeters above the fistula
and then ligation of the artery just below and this has grown in popularity certainly over the last 10 or 15 years as the go to procedure. Because there is no flow restriction with this you don't sacrifice patency of the access for it. It does add additional distal flow to the extremity.
It's definitely a more morbid procedure. It involves generally harvesting the saphenous vein from patients that may not be the best risk surgical patients, but again, it's a good choice for low flow fistula. RUDI, revision using distal inflow, is basically
a flow restrictive procedure just like banding. You're simply, it's a little bit more complicated 'cause you're usually doing a vein graft from the radial artery to the fistula. But it's less complicated than DRIL. Similar limitations to banding.
Very limited clinical data. There's really just a few series of fewer than a dozen patients each to go by. Finally, a proximalization of arterial inflow, in this case rather than ligating the brachial artery you're ligating the fistula and going to a more proximal
vessel that often will accommodate higher flow. In our hands, we were often talking about going to the infraclavicular axillary artery. So, it's definitely more morbid than a banding would be. This is a better choice though for prosthetic grafts that, where you want to preserve flow.
Again, data on this is very limited as well. The (mumbles) a couple years ago they asked the audience what they like and clearly DRIL has become the most popular choice at 60%, but about 20% of people were still going to banding, and so my charge was to say when is banding
the right way to go. Again, it's effect is less predictable than DRIL. You definitely are going to slow the flows down, but remember with DRIL you are making the limb dependent on the patency of that graft which is always something of concern in somebody
who you have caused an ischemic hand in the first place, and again, the morbidity with the DRIL certainly more so than with the band. We looked at our results a few years back and we identified 31 patients who had steal. Most of these, they all had a physiologic test
confirming the diagnosis. All had some degree of pain or numbness. Only three of these patients had gangrene or ulcers. So, a relatively small cohort of limb, of advanced steal. Most of our patients were autogenous access,
so ciminos and brachycephalic fistula, but there was a little bit of everything mixed in there. The mean age was 66. 80% were diabetic. Patients had their access in for about four and a half months on average at the time of treatment,
although about almost 40% were treated within three weeks of access placement. This is how we do the banding. We basically expose the arterial anastomosis and apply wet clips trying to get a diameter that is less than the brachial artery.
It's got to be smaller than the brachial artery to do anything, and we monitor either pulse volume recordings of the digits or doppler flow at the palm or arch and basically apply these clips along the length and restricting more and more until we get
a satisfactory signal or waveform. Once we've accomplished that, we then are satisfied with the degree of narrowing, we then put some mattress sutures in because these clips will fall off, and fix it in place.
And basically this is the result you get. You go from a fistula that has no flow restriction to one that has restriction as seen there. What were our results? Well, at follow up that was about almost 16 months we found 29 of the 31 patients had improvement,
immediate improvement. The two failures, one was ligated about 12 days later and another one underwent a DRIL a few months later. We had four occlusions in these patients over one to 18 months. Two of these were salvaged with other procedures.
We only had two late recurrences of steal in these patients and one of these was, recurred when he was sent to a radiologist and underwent a balloon angioplasty of the banding. And we had no other morbidity. So this is really a very simple procedure.
So, this is how it compares with DRIL. Most of the pooled data shows that DRIL is effective in 90 plus percent of the patients. Patency also in the 80 to 90% range. The DRIL is better for late, or more often used in late patients,
and banding used more in earlier patients. There's a bigger blood pressure change with DRIL than with banding. So you definitely get more bang for the buck with that. Just quickly going through the literature again. Ellen Dillava's group has published on this.
DRIL definitely is more accepted. These patients have very high mortality. At two years 50% are going to be dead. So you have to keep in mind that when you're deciding what to do. So, I choose banding when there's no gangrene,
when there's moderate not severe pain, and in patients with high morbidity. As promised here's an algorithm that's a little complicated looking, but that's what we go by. Again, thanks very much.
- Thank you again for the opportunity to discuss the BlueLeaf Endovenous Valve with potential benefits of on an all-autogenous solution. The last slide was a nice segue to this presentation, so the financial relationship. So we've discussed extensively at this meeting treatments for superficial venous
reflux outflow obstruction, and, really, the last sort of frontier is the deep vein reflux where invasive surgery is still the gold standard, but I basically say that the majority of us, or at least myself and many of us in our practice,
resort to what I refer to as palliative care or conservative managements in patients who have maximally been treated for their outflow obstruction and superficial venous reflux. This is sort of an outstanding review
of the current state of deep venous reconstructive surgery by Dr. Maleti, Lugli, and Tripathi who said the trap door technique as well as the neovalve and the corresponding outcomes, and I encourage all of you to look at it, are pretty reassuring even with the limitations.
The ulcer recurrence rates are in the 20-30% range and the vales remain competent in 70% of cases, and the results of the neovalve reconstruction are also reasonably promising. So how do we take these reasonably and pretty promising results and try to expand them?
Potentially, what would it look like as a percutaneous approach? And it might look something like this. And this is the BlueLeaf Endovenous Valve Formation System which uses a catheter system, a nitinol dissector, and a needle assembly,
and it's done under intravascular ultrasound guidance. This is what the procedure looks like in the basic three steps. After you've gained access with a 16 French sheath in the common femoral vein you identify the valve site,
the appropriate valve site with the IVUS, you perform, you gain sub-intimal access, and then perform the hydrodissection, and then you create your valve. And this is how it goes. So after you've gained wire access
you advance your intravascular ultrasound in order to identify the valve formation site. Right now it's quantitated at seven to 11 millimeters in diameter and at least three centimeters in length. You then inflate the balloon to appose the vein wall,
to create some tension in the vein wall, and thereafter your needle assembly can create that sub-intimal plane with the hydrodissection, and you see how the bevel tip retracts to make it less traumatic. You're checking with intravascular ultrasound.
You advance the dissector. And then under IVUS guidance you create the valve with the nitinol scoring blades on the dissector as well as the tensioner which kind of bows out towards the IVUS, and you can see it on the corresponding IVUS images.
And the very last step is to leave the blades open to open up the mouth of that percutaneous valve fully. And the advantages. You can create a monocuspid, a bicuspid valve, potentially multilevel valves as well. In this tissue demonstration
you're essentially looking from within the vein walls, so the tensioner is pointing out towards you as if you're within the lumen of the vessel, and it's just showing you how the nitinol scoring blades create the valve and then when left open for the final passage
to incise the valve mouth. And this is what the result looks like on intravascular ultrasound. It projects well the last couple seconds of the slide. So the potential advantages is that there's an increased potential for customization.
Again, monocuspid, bicuspid valve orientation, multilevel valves. (mumbles) may lead to a larger eligible patient population and expanded utilization amongst various venous practitioners. The extended feasibility study.
The trial details are currently enrolling outside of the United States. 11 patient in Australia and New Zealand. The US trial is pending IDE approval, and the inclusion criteria will be those patients with the most severe disease with C5 and C6 disease
and significant deep vein reflux. Exclusion criteria relate to inflow, outflow, and having an adequate conduit with an appropriate valve formation site. Thank you.
- 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.
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