Thanks very much, Tom. I'll be talking about thermal ablation on anticoagula is it safe and effective? I have no disclosures. As we know, extensive review of both RF and laser
ablation procedures have demonstrated excellent treatment effectiveness and durability in each modality, but there is less data regarding treatment effectiveness and durability for those procedures in patients who are also on systemic anticoagulation. As we know, there's multiple studies have been done
over the past 10 years, with which we're all most familiar showing a percent of the durable ablation, both modalities from 87% to 95% at two to five years. There's less data on those on the anticoagulation undergoing thermal ablation.
The largest study with any long-term follow up was by Sharifi in 2011, and that was 88 patients and follow-up at one year. Both RF and the EVLA had 100% durable ablation with minimal bleeding complications. The other studies were all smaller groups
or for very much shorter follow-up. In 2017, a very large study came out, looking at the EVLA and RF using 375 subjects undergoing with anticoagulation. But it was only a 30-day follow-up, but it did show a 30% durable ablation
at that short time interval. Our objective was to evaluate efficacy, durability, and safety of RF and EVLA, the GSV and the SSV to treat symptomatic reflux in patients on therapeutic anticoagulation, and this group is with warfarin.
The data was collected from NYU, single-center. Patients who had undergone RF or laser ablation between 2011 and 2013. Ninety-two vessels of patients on warfarin at the time of endothermal ablation were selected for study. That's the largest to date with some long-term follow-up.
And this group was compared to a matched group of 124 control patients. Devices used were the ClosureFast catheter and the NeverTouch kits by Angiodynamics. Technical details, standard IFU for the catheters. Tumescent anesthetic.
And fiber tips were kept about 2.5 centimeters from the SFJ or the SPJ. Vein occlusion was defined as the absence of blood flow by duplex scan along the length of the treated vein. You're all familiar with the devices, so the methods included follow-up, duplex ultrasound
at one week post-procedure, and then six months, and then also at a year. And then annually. Outcomes were analyzed with Kaplan-Meier plots and log rank tests. The results of the anticoagulation patients, 92,
control, 124, the mean follow-up was 470 days. And you can see that the demographics were rather similar between the two groups. There was some more coronary disease and hypertension in the anticoagulated groups, and that's really not much of a surprise
and some more male patients. Vessels treated, primarily GSV. A smaller amount of SSV in both the anticoagulated and the control groups. Indications for anticoagulation.
About half of the patients were in atrial fibrillation. Another 30% had a remote DVT in the contralateral limb. About 8% had mechanical valves, and 11% were for other reasons. And the results. The persistent vein ablation at 12 months,
the anticoagulation patients was 97%, and the controls was 99%. Persistent vein ablation by treated vessel, on anticoagulation. Didn't matter if it was GSV or SSV. Both had persistent ablation,
and by treatment modality, also did not matter whether it was laser or RF. Both equivalent. If there was antiplatelet therapy in addition to the anticoagulation, again if you added aspirin or Clopidogrel,
also no change. And that was at 12 months. We looked then at persistent vein ablation out at 18 months. It was still at 95% for the controls, and 91% for the anticoagulated patients. Still not statistically significantly different.
At 24 months, 89% in both groups. Although the numbers were smaller at 36 months, there was actually still no statistically significant difference. Interestingly, the anticoagulated group actually had a better persistent closure rate
than the control group. That may just be because the patients that come back at 36 months who didn't have anticoagulation may have been skewed. The ones we actually saw were ones that had a problem. It gets harder to have patients
come back at three months who haven't had an uneventful venous ablation procedure. Complication, no significant hematomas. Three patients had DVTs within 30 days. One anticoagulation patient had a popliteal DVT, and one control patient.
And one control patient had a calf vein DVT. Two EHITs. One GSV treated with laser on anticoagulation noted at six days, and one not on anticoagulation at seven days. Endovenous RF and EVLA can be safely performed
in patients undergoing long-term warfarin therapy. Our experience has demonstrated a similar short- and mid-term durability for RF ablation and laser, and platelet therapy does not appear to impact the closer rates,
which is consistent with the prior studies. And the frequency of vein recanalization following venous ablation procedures while on ACs is not worse compared to controls, and to the expected incidence as described in the literature.
This is the largest study to date with follow-up beyond 30 days with thermal ablation procedures on anticoagulation patients. We continue to look at these patients for even longer term durability. Thanks very much for your attention.
- Thanks Dr. Weaver. Thank you Dr. Reed for the invitation, once again, to this great meeting. These are my disclosures. So, open surgical repair of descending aortic arch disease still carries some significant morbidity and mortality.
And obviously TEVAR as we have mentioned in many of the presentations has become the treatment of choice for appropriate thoracic lesions, but still has some significant limitations of seal in the aortic arch and more techniques are being developed to address that.
Right now, we also need to cover the left subclavian artery and encroach or cover the left common carotid artery for optimal seal, if that's the area that we're trying to address. So zone 2, which is the one that's,
it is most commonly used as seal for the aortic arch requires accurate device deployment to maximize the seal and really avoid ultimately, coverage of the left common carotid artery and have to address it as an emergency. Seal, in many of these cases is not maximized
due to the concern of occlusion of the left common carotid artery and many of the devices are deployed without obtaining maximum seal in that particular area. Failure of accurate deployment often leads to a type IA endoleak or inadvertent coverage
of the left common carotid artery which can become a significant problem. The most common hybrid procedures in this group of patients include the use of TEVAR, a carotid-subclavian reconstruction and left common carotid artery stenting,
which is hopefully mostly planned, but many of the times, especially when you're starting, it may be completely unplanned. The left common carotid chimney has been increasingly used to obtain a better seal
in this particular group of patients with challenging arches, but there's still significant concerns, including patients having super-vascular complications, stroke, Type A retrograde dissections and a persistent Type IA endoleak
which can be very challenging to be able to correct. There's limited data to discuss this specific topic, but some of the recent publications included a series of 11 to 13 years of treatment with a variety of chimneys.
And these publications suggest that the left common carotid chimneys are the most commonly used chimneys in the aortic arch, being used 76% to 89% of the time in these series. We can also look at these and the technical success
is very good. Mortality's very low. The stroke rate is quite variable depending on the series and chimney patency's very good. But we still have a relatively high persistent
Type IA endoleak on these procedures. So what can we do to try to improve the results that we have? And some of these techniques are clearly applicable for elective or emergency procedures. In the elective setting,
an open left carotid access and subclavian access can be obtained via a supraclavicular approach. And then a subclavian transposition or a carotid-subclavian bypass can be performed in preparation for the endovascular repair. Following that reconstruction,
retrograde access to left common carotid artery can be very helpful with a 7 French sheath and this can be used for diagnostic and therapeutic purposes at the same time. The 7 French sheath can easily accommodate most of the available covered and uncovered
balloon expandable stents if the situation arises that it's necessary. Alignment of the TEVAR is critical with maximum seal and accurate placement of the TEVAR at this location is paramount to be able to have a good result.
At that point, the left common carotid artery chimney can be deployed under control of the left common carotid artery. To avoid any embolization, the carotid can be flushed, primary repaired, and the subclavian can be addressed
if there is concern of a persistent retrograde leak with embolization with a plug or other devices. The order can be changed for the procedure to be able to be done emergently as it is in this 46 year old policeman with hypertension and a ruptured thoracic aneurism.
The patient had the left common carotid access first, the device deployed appropriately, and the carotid-subclavian bypass performed in a more elective fashion after the rupture had been addressed. So, in conclusion, carotid chimney's and TEVAR
combination is a frequently used to obtain additional seal on the aortic arch, with pretty good results. Early retrograde left common carotid access allows safe TEVAR deployment with maximum seal,
and the procedure can be safely performed with low morbidity and mortality if we select the patients appropriately. Thank you very much.
- Thank you. Historically, common femoral endarterectomy is a safe procedure. In this quick publication that we did several years ago, showed a 1.5% 30 day mortality rate. Morbidity included 6.3% superficial surgical site infection.
Other major morbidity was pretty low. High-risk patients we identified as those that were functionally dependent, dyspnea, obesity, steroid use, and diabetes. A study from Massachusetts General Hospital their experience showed 100% technical success.
Length of stay was three days. Primary patency of five years at 91% and assisted primary patency at five years 100%. Very little perioperative morbidity and mortality. As you know, open treatment has been the standard of care
over time the goal standard for a common femoral disease, traditionally it's been thought of as a no stent zone. However, there are increased interventions of the common femoral and deep femoral arteries. This is a picture that shows inflection point there.
Why people are concerned about placing stents there. Here's a picture of atherectomy. Irritational atherectomy, the common femoral artery. Here's another image example of a rotational atherectomy, of the common femoral artery.
And here's an image of a stent there, going across the stent there. This is a case I had of potential option for stenting the common femoral artery large (mumbles) of the hematoma from the cardiologist. It was easily fixed
with a 2.5 length BioBond. Which I thought would have very little deformability. (mumbles) was so short in the area there. This is another example of a complete blow out of the common femoral artery. Something that was much better
treated with a stent that I thought over here. What's the data on the stenting of the endovascular of the common femoral arteries interventions? So, there mostly small single centers. What is the retrospective view of 40 cases?
That shows a restenosis rate of 19.5% at 12 months. Revascularization 14.1 % at 12 months. Another one by Dr. Mehta shows restenosis was observed in 20% of the patients and 10% underwent open revision. A case from Dr. Calligaro using cover stents
shows very good primary patency. We sought to use Vascular Quality Initiative to look at endovascular intervention of the common femoral artery. As you can see here, we've identified a thousand patients that have common femoral interventions, with or without,
deep femoral artery interventions. Indications were mostly for claudication. Interventions include three-quarters having angioplasty, 35% having a stent, and 20% almost having atherectomy. Overall technical success was high, a 91%.
Thirty day mortality was exactly the same as in this clip data for open repair 1.6%. Complications were mostly access site hematoma with a low amount distal embolization had previously reported. Single center was up to 4%.
Overall, our freedom for patency or loss or death was 83% at one year. Predicted mostly by tissue loss and case urgency. Re-intervention free survival was 85% at one year, which does notably include stent as independent risk factor for this.
Amputation free survival was 93% at one year, which factors here, but also stent was predictive of amputation. Overall, we concluded that patency is lower than historical common femoral interventions. Mortality was pretty much exactly the same
that has been reported previously. And long term analysis is needed to access durability. There's also a study from France looking at randomizing stenting versus open repair of the common femoral artery. And who needs to get through it quickly?
More or less it showed no difference in outcomes. No different in AVIs. Higher morbidity in the open group most (mumbles) superficial surgical wound infections and (mumbles). The one thing that has hit in the text of the article
a group of mostly (mumbles) was one patient had a major amputation despite having a patent common femoral artery stent. There's no real follow up this, no details of this, I would just caution of both this and VQI paper showing increased risk amputation with stenting.
- These are my disclosures. So central venous access is frequently employed throughout the world for a variety of purposes. These catheters range anywhere between seven and 11 French sheaths. And it's recognized, even in the best case scenario, that there are iatrogenic arterial injuries
that can occur, ranging between three to 5%. And even a smaller proportion of patients will present after complications from access with either a pseudoaneurysm, fistula formation, dissection, or distal embolization. In thinking about these, as you see these as consultations
on your service, our thoughts are to think about it in four primary things. Number one is the anatomic location, and I think imaging is very helpful. This is a vas cath in the carotid artery. The second is th
how long the device has been dwelling in the carotid or the subclavian circulation. Assessment for thrombus around the catheter, and then obviously the size of the hole and the size of the catheter.
Several years ago we undertook a retrospective review and looked at this, and we looked at all carotid, subclavian, and innominate iatrogenic injuries, and we excluded all the injuries that were treated, that were manifest early and treated with just manual compression.
It's a small cohort of patients, we had 12 cases. Eight were treated with a variety of endovascular techniques and four were treated with open surgery. So, to illustrate our approach, I thought what I would do is just show you four cases on how we treated some of these types of problems.
The first one is a 75 year-old gentleman who's three days status post a coronary bypass graft with a LIMA graft to his LAD. He had a cordis catheter in his chest on the left side, which was discovered to be in the left subclavian artery as opposed to the vein.
So this nine French sheath, this is the imaging showing where the entry site is, just underneath the clavicle. You can see the vertebral and the IMA are both patent. And this is an angiogram from a catheter with which was placed in the femoral artery at the time that we were going to take care of this
with a four French catheter. For this case, we had duel access, so we had access from the groin with a sheath and a wire in place in case we needed to treat this from below. Then from above, we rewired the cordis catheter,
placed a suture-mediated closure device, sutured it down, left the wire in place, and shot this angiogram, which you can see very clearly has now taken care of the bleeding site. There's some pinching here after the wire was removed,
this abated without any difficulty. Second case is a 26 year-old woman with a diagnosis of vascular EDS. She presented to the operating room for a small bowel obstruction. Anesthesia has tried to attempt to put a central venous
catheter access in there. There unfortunately was an injury to the right subclavian vein. After she recovered from her operation, on cross sectional imaging you can see that she has this large pseudoaneurysm
coming from the subclavian artery on this axial cut and also on the sagittal view. Because she's a vascular EDS patient, we did this open brachial approach. We placed a stent graft across the area of injury to exclude the aneurism.
And you can see that there's still some filling in this region here. And it appeared to be coming from the internal mammary artery. We gave her a few days, it still was patent. Cross-sectional imaging confirmed this,
and so this was eventually treated with thoracoscopic clipping and resolved flow into the aneurism. The next case is a little bit more complicated. This is an 80 year-old woman with polycythemia vera who had a plasmapheresis catheter,
nine French sheath placed on the left subclavian artery which was diagnosed five days post procedure when she presented with a posterior circulation stroke. As you can see on the imaging, her vertebral's open, her mammary's open, she has this catheter in the significant clot
in this region. To manage this, again, we did duel access. So right femoral approach, left brachial approach. We placed the filter element in the vertebral artery. Balloon occlusion of the subclavian, and then a stent graft coverage of the area
and took the plasmapheresis catheter out and then suction embolectomy. And then the last case is a 47 year-old woman who had an attempted right subclavian vein access and it was known that she had a pulsatile mass in the supraclavicular fossa.
Was noted to have a 3cm subclavian artery pseudoaneurysm. Very broad base, short neck, and we elected to treat this with open surgical technique. So I think as you see these consults, the things to factor in to your management decision are: number one, the location.
Number two, the complication of whether it's thrombus, pseudoaneurysm, or fistula. It's very important to identify whether there is pericatheter thrombus. There's a variety of techniques available for treatment, ranging from manual compression,
endovascular techniques, and open repair. I think the primary point here is the prevention with ultrasound guidance is very important when placing these catheters. Thank you. (clapping)
- Thank you very much indeed, and, first of all, I'd like to thank you for allowing me to come to the show and speak about these things. It's a great pleasure and of course to Frank Veith, who has a marvelous, created a marvelous thing
for all of us over the years to interact. Here are my disclosures. VTE is mostly a chronic inflammatory disease that is often not cured with short anticoagulation. Thrombosis is inextricably linked to inflammation and immunologic changes,
and I believe we should discard the simplistic notion that we can decide how long to anticoagulate the patients based upon this simplistic criteria of provoked versus unprovoked. As we all know, life is complicated. We know that Factor VIII is a potent
predictor for first venous thrombosis. Levels are constant, unaffected by anticoagulation. Three months of anticoagulation, after three months off anticoagulation, the vitamin K levels are not affected. And this was a study follow-up of 6.9 years,
and the recurrent VTE was 1.6 for each increase of 10 deciliters of Factor VIII. Cumulative index rates for both provoked and unprovoked are seen, and those with a level of over 200, sorry about that, Factor VIII... Those with the level of greater than 200
had a three-fold higher risk compared to those with a Factor VIII equal to or less than 100 international units. And here you can see on this chart as you go up above 200, 9.5% one year, 30% at five years, 4.4% at one year, and almost 20% at five years,
and so that is significant. But what's more significant and has not been carefully looked at, is the synergistic effect between Factor VIII and vita--. Factor VIII and D-dimer. And if one is abnormal,
the recurrence rate in this study was 6.4% And if both were normal, it was 6.4%. If one was abnormal, it was almost up to 18%. And if both were abnormal, it was 34%. And here, you can see the curves clearly for that. And here, we have a look at--and this is the latest data
and most compelling data about the lack of differences between provoked and unprovoked in cancer patients. And you can see if you look, provoked is the red line. Unprovoked is the black, dark line, and green is cancer-related VTE. So that you can see how similar these are, and
talking about residual obstruction, which I think is very important and I have studied for years. The presence of residual venous obstruction, which, you know, after a while, is not clot but it turns into fibrous material. And the cumulative recurrence rate,
according to Prandoni, was 40%, with a provoked rate of 22 and an unprovoked of 52. And these data force us to question the notion that time-limited anticoagulation is an effective strategy because the rate of recurrence is high, even among those with provoked VTE.
Now I don't totally subscribe to what he said about this compression and 40% of the diameter. You have to take a look at the overall vein and if the overall vein there is significant changes in it, then I think that that influences whether or not you should continue your anticoagulation.
The Achilles heel of this, is that nobody knows for sure how to quantify these changes. And if you take a look, for example, this was a CAT Scan of somebody after three months of a provoked, simple clot. And I always scan them and I would not stop
the anticoagulation in this patient, and you would see because of the reflex and so forth, eventually this patient is going to show signs of post-embolic syndrome, venous insufficiency, but also, I think, has an increase risk of thrombosis. Again, here's another one with significant clot
in the popliteal facet, after what was thought to be a very minor insult. And here we go again on cross sections. So these are the kind of images, once you start looking at them, and I'd encourage you, in some of these patients, to take a look at them
because I think it's very important that these with these changes about continuing anticoagulation. Now, I'm sorry about this, but this is really important. If somebody has a normal D-dimer, a normal Factor VIII, and a normal scan, on anticoagulation, we'll stop it. And then 30 days, 90 days, and 180 days later,
repeat the Factor VIII and D-dimer. And that's assuming that their scan is clean. If they're normal throughout that whole period, then we would consider them to stay off of anticoagulation. And the other thing is that, one of the things that I think is really good about this,
is that now we have very effective modalities for long term anticoagulation, so that I think you ought to take a look at much more beyond time-related criteria. Thank you very much.
- Thank you for asking me to speak. Thank you Dr Veith. I have no disclosures. I'm going to start with a quick case again of a 70 year old female presented with right lower extremity rest pain and non-healing wound at the right first toe
and left lower extremity claudication. She had non-palpable femoral and distal pulses, her ABIs were calcified but she had decreased wave forms. Prior anterior gram showed the following extensive aortoiliac occlusive disease due to the small size we went ahead and did a CT scan and confirmed.
She had a very small aorta measuring 14 millimeters in outer diameter and circumferential calcium of her aorta as well as proximal common iliac arteries. Due to this we treated her with a right common femoral artery cutdown and an antegrade approach to her SFA occlusion with a stent.
We then converted the sheath to a retrograde approach, place a percutaneous left common femoral artery access and then placed an Endologix AFX device with a 23 millimeter main body at the aortic bifurcation. We then ballooned both the aorta and iliac arteries and then placed bilateral balloon expandable
kissing iliac stents to stent the outflow. Here is our pre, intra, and post operative films. She did well. Her rest pain resolved, her first toe amputation healed, we followed her for about 10 months. She also has an AV access and had a left arterial steel
on a left upper extremity so last week I was able to undergo repeat arteriogram and this is at 10 months out. We can see that he stent remains open with good flow and no evidence of in stent stenosis. There's very little literature about using endografts for occlusive disease.
Van Haren looked at 10 patients with TASC-D lesions that were felt to be high risk for aorta bifem using the Endologix AFX device. And noted 100% technical success rate. Eight patients did require additional stent placements. There was 100% resolution of the symptoms
with improved ABIs bilaterally. At 40 months follow up there's a primary patency rate of 80% and secondary of 100% with one acute limb occlusion. Zander et all, using the Excluder prothesis, looked at 14 high risk patients for aorta bifem with TASC-C and D lesions of the aorta.
Similarly they noted 100% technical success. Nine patients required additional stenting, all patients had resolution of their symptoms and improvement of their ABIs. At 62 months follow up they noted a primary patency rate of 85% and secondary of 100
with two acute limb occlusions. The indications for this procedure in general are symptomatic patient with a TASC C or D lesion that's felt to either be a high operative risk for aorta bifem or have a significantly calcified aorta where clamping would be difficult as we saw in our patient.
These patients are usually being considered for axillary bifemoral bypass. Some technical tips. Access can be done percutaneously through a cutdown. I do recommend a cutdown if there's femoral disease so you can preform a femoral endarterectomy and
profundaplasty at the same time. Brachial access is also an alternative option. Due to the small size and disease vessels, graft placement may be difficult and may require predilation with either the endograft sheath dilator or high-pressure balloon.
In calcified vessels you may need to place covered stents in order to pass the graft to avoid rupture. Due to the poor radial force of endografts, the graft must be ballooned after placement with either an aortic occlusion balloon but usually high-pressure balloons are needed.
It usually also needs to be reinforced the outflow with either self-expanding or balloon expandable stents to prevent limb occlusion. Some precautions. If the vessels are calcified and tortuous again there may be difficult graft delivery.
In patients with occluded vessels standard techniques for crossing can be used, however will require pre-dilation before endograft positioning. If you have a sub intimal cannulation this does put the vessel at risk for rupture during
balloon dilation. Small aortic diameters may occlude limbs particularly using modular devices. And most importantly, the outflow must be optimized using stents distally if needed in the iliac arteries, but even more importantly, assuring that you've
treated the femoral artery and outflow to the profunda. Despite these good results, endograft use for occlusive disease is off label use and therefor not reimbursed. In comparison to open stents, endograft use is expensive and may not be cost effective. There's no current studies looking
into the cost/benefit ratio. Thank you.
- I think by definition this whole session today has been about challenging vascular access cases. Here's my disclosures. I went into vascular surgery, I think I made the decision when I was either a fourth year medical student or early on in internship because
what intrigued me the most was that it seemed like vascular surgeons were only limited by their imagination in what we could do to help our patients and I think these access challenges are perfect examples of this. There's going to be a couple talks coming up
about central vein occlusion so I won't be really touching on that. I just have a couple of examples of what I consider challenging cases. So where do the challenges exist? Well, first, in creating an access,
we may have a challenge in trying to figure out what's going to be the best new access for a patient who's not ever had one. Then we are frequently faced with challenges of re-establishing an AV fistula or an AV graft for a patient.
This may be for someone who's had a complication requiring removal of their access, or the patient who was fortunate to get a transplant but then ended up with a transplant rejection and now you need to re-establish access. There's definitely a lot of clinical challenges
maintaining access: Treating anastomotic lesions, cannulation zone lesions, and venous outflow pathology. And we just heard a nice presentation about some of the complications of bleeding, infection, and ischemia. So I'll just start with a case of a patient
who needed to establish access. So this is a 37-year-old African-American female. She's got oxygen-dependent COPD and she's still smoking. Her BMI is 37, she's left handed, she has diabetes, and she has lupus. Her access to date - now she's been on hemodialysis
for six months, all through multiple tunneled catheters that have been repeatedly having to be removed for infection and she was actually transferred from one of our more rural hospitals into town because she had a infected tunneled dialysis catheter in her femoral region.
She had been deemed a very poor candidate for an AV fistula or AV graft because of small veins. So the challenges - she is morbidly obese, she needs immediate access, and she has suboptimal anatomy. So our plan, again, she's left handed. We decided to do a right upper extremity graft
but the plan was to first explore her axillary vein and do a venogram. So in doing that, we explored her axillary vein, did a venogram, and you can see she's got fairly extensive central vein disease already. Now, she had had multiple catheters.
So this is a venogram through a 5-French sheath in the brachial vein in the axilla, showing a diffusely diseased central vein. So at this point, the decision was made to go ahead and angioplasty the vein with a 9-millimeter balloon through a 9-French sheath.
And we got a pretty reasonable result to create venous outflow for our planned graft. You can see in the image there, for my venous outflow I've placed a Gore Hybrid graft and extended that with a Viabahn to help support the central vein disease. And now to try and get rid of her catheters,
we went ahead and did a tapered 4-7 Acuseal graft connected to the brachial artery in the axilla. And we chose the taper mostly because, as you can see, she has a pretty small high brachial artery in her axilla. And then we connected the Acuseal graft to the other end of the Gore Hybrid graft,
so at least in the cannulation zone we have an immediate cannualation graft. And this is the venous limb of the graft connected into the Gore hybrid graft, which then communicates directly into the axillary vein and brachiocephalic vein.
So we were able to establish a graft for this patient that could be used immediately, get rid of her tunneled catheter. Again, the challenges were she's morbidly obese, she needs immediate access, and she has suboptimal anatomy, and the solution was a right upper arm loop AV graft
with an early cannulation segment to immediately get rid of her tunneled catheter. Then we used the Gore Hybrid graft with the 9-millimeter nitinol-reinforced segment to help deal with the preexisting venous outflow disease that she had, and we were able to keep this patient
free of a catheter with a functioning access for about 13 months. So here's another case. This is in a steal patient, so I think it's incredibly important that every patient that presents with access-induced ischemia to have a complete angiogram
of the extremity to make sure they don't have occult inflow disease, which we occasionally see. So this patient had a functioning upper arm graft and developed pretty severe ischemic pain in her hand. So you can see, here's the graft, venous outflow, and she actually has,
for the steal patients we see, she actually had pretty decent flow down her brachial artery and radial and ulnar artery even into the hand, even with the graft patent, which is usually not the case. In fact, we really challenged the diagnosis of ischemia for quite some time, but the pressures that she had,
her digital-brachial index was less than 0.5. So we went ahead and did a drill. We've tried to eliminate the morbidity of the drill bit - so we now do 100% of our drills when we're going to use saphenous vein with endoscopic vein harvest, which it's basically an outpatient procedure now,
and we've had very good success. And here you can see the completion angiogram and just the difference in her hand perfusion. And then the final case, this is a patient that got an AV graft created at the access center by an interventional nephrologist,
and in the ensuing seven months was treated seven different times for problems, showed up at my office with a cold blue hand. When we duplexed her, we couldn't see any flow beyond the AV graft anastomosis. So I chose to do a transfemoral arteriogram
and what you can see here, she's got a completely dissected subclavian axillary artery, and this goes all the way into her arterial anastomosis. So this is all completely dissected from one of her interventions at the access center. And this is the kind of case that reminded me
of one of my mentors, Roger Gregory. He used to say, "I don't wan "I just want out of the trap." So what we ended up doing was, I actually couldn't get into the true lumen from antegrade, so I retrograde accessed
her brachial artery and was able to just re-establish flow all the way down. I ended up intentionally covering the entry into her AV graft to get that out of the circuit and just recover her hand, and she's actually been catheter-dependent ever since
because she really didn't want to take any more chances. Thank you very much.
- Our group has looked at the outcomes of patients undergoing carotid-subclavian bypass in the setting of thoracic endovascular repair. These are my obligatory disclosures, none of which are relevant to this study. By way of introduction, coverage of the left subclavian artery origin
is required in 10-50% of patients undergoing TEVAR, to achieve an adequate proximal landing zone. The left subclavian artery may contribute to critical vascular beds in addition to the left upper extremity, including the posterior cerebral circulation,
the coronary circulation if a LIMA graft is present, and the spinal cord, via vertebral collaterals. Therefore the potential risks of inadequate left subclavian perfusion include not only arm ischemia, but also posterior circulation stroke,
spinal cord ischemia, and coronary insufficiency. Although these risks are of low frequency, the SVS as early as 2010 published guidelines advocating a policy of liberal left subclavian revascularization during TEVAR
requiring left subclavian origin coverage. Until recently, the only approved way to maintain perfusion of the left subclavian artery during TEVAR, with a zone 2 or more proximal landing zone, was a cervical bypass or transposition procedure. As thoracic side-branch devices become more available,
we thought it might be useful to review our experience with cervical bypass for comparison with these newer endovascular strategies. This study was a retrospective review of our aortic disease database, and identified 112 out of 579 TEVARs
that had undergone carotid subclavian bypass. We used the standard operative technique, through a short, supraclavicular incision, the subclavian arteries exposed by division of the anterior scalene muscle, and a short 8 millimeter PTFE graft is placed
between the common carotid and the subclavian arteries, usually contemporaneous with the TEVAR procedure. The most important finding of this review regarded phrenic nerve dysfunction. To exam this, all pre- and post-TEVAR chest x-rays were reviewed for evidence of diaphragm elevation.
The study population was typical for patients undergoing TEVAR. The most frequent indication for bypass was for spinal cord protection, and nearly 80% of cases were elective. We found that 25 % of patients had some evidence
of phrenic nerve dysfunction, though many resolved over time. Other nerve injury and vascular graft complications occurred with much less frequency. This slide illustrates the grading of diaphragm elevation into mild and severe categories,
and notes that over half of the injuries did resolve over time. Vascular complications were rare, and usually treated with a corrective endovascular procedure. Of three graft occlusions, only one required repeat bypass.
Two pseudoaneurysms were treated endovascularly. Actuarial graft, primary graft patency, was 97% after five years. In summary then, the report examines early and late outcomes for carotid subclavian bypass, in the setting of TEVAR. We found an unexpectedly high rate
of phrenic nerve dysfunction postoperatively, although over half resolved spontaneously. There was a very low incidence of vascular complications, and a high long-term patency rate. We suggest that this study may provide a benchmark for comparison
with emerging branch thoracic endovascular devices. Thank you.
- Well, thank you Frank and Enrico for the privilege of the podium and it's the diehards here right now. (laughs) So my only disclosure, this is based on start up biotech company that we have formed and novel technology really it's just a year old
but I'm going to take you very briefly through history very quickly. Hippocrates in 420 B.C. described stroke for the first time as apoplexy, someone be struck down by violence. And if you look at the history of stroke,
and trying to advance here. Let me see if there's a keyboard. - [Woman] Wait, wait, wait, wait. - [Man] No, there's no keyboard. - [Woman] It has to be opposite you. - [Man] Left, left now.
- Yeah, thank you. Are we good? (laughs) So it's not until the 80s that really risk factors for stroke therapy were identified, particularly hypertension, blood pressure control,
and so on and so forth. And as we go, could you advance for me please? Thank you, it's not until the 90s that we know about the randomized carotid trials, and advance next slide please, really '96 the era of tPA that was
revolutionary for acute stroke therapy. In the early 2000s, stroke centers, like the one that we have in the South East Louisiana and New Orleans really help to coordinate specialists treating stroke. Next slide please.
In 2015, the very famous HERMES trial, the compilation of five trials for mechanical thrombectomy of intracranial middle and anterior cerebral described the patients that could benefit and we will go on into details, but the great benefit, the number needed to treat
was really five to get an effect. Next slide. This year, "wake up" strokes, the extension of the timeline was extended to 24 hours, increase in potentially the number of patients that could be treated with this technology.
Next please. And the question is really how can one preserve the penumbra further to treat the many many patients that are still not offered mechanical thrombectomy and even the ones that are, to get a much better outcome because not everyone
returns to a normal function. Next, so the future I think is going to be delivery of a potent neuroprotection strategy to the penumbra through the stroke to be able to preserve function and recover the penumbra from ongoing death.
Next slide. So that's really the history of stroke. Advance to the next please. Here what you can see, this is a patient of mine that came in with an acute carotid occlusion that we did an emergency carotid endarterectomy
with an neuro interventionalist after passage of aspiration catheter, you can see opening of the middle cerebral M1 and M2 branches. The difference now compared to five, eight, 10 years ago is that now we have catheters in the middle cerebral artery,
the anterior cerebral artery. After tPA and thrombectomy for the super-selective, delivery of a potent neuroprotective agent and by being able to deliver it super-selectively, bioavailability issues can be resolved, systemic side effects could be minimized.
Of course, it's important to remember that penumbra is really tissue at risk, that's progression towards infarction. And everybody is really different as to when this occurs. And it's truly all based on collaterals.
So "Time is brain" that we hear over and over again, at this meeting there were a lot of talks about "Time is brain" is really incorrect. It's really "Collaterals are brain" and the penumbra is really completely based on what God gives us when we're born, which is really
how good are the collaterals. So the question is how can the penumbra be preserved after further mechanical thrombectomy? And I think that the solution is going to be with potent neuroprotection delivery to the penumbra. These are two papers that we published in late 2017
in Nature, in science journals Scientific Reports and Science Advances by our group demonstrating a novel class of molecules that are potent neuroprotective molecules, and we will go into details, but we can discuss it if there's interest, but that's just one candidate.
Because after all, when we imaged the penumbra in acute stroke centers, again, it's all about collaterals and I'll give you an example. The top panel is a patient that comes in with a good collaterals, this is a M1 branch occlusion. In these three phases which are taken at
five second intervals, this patient is probably going to be offered therapy. The patients that come in with intermediate or poor collaterals may or may not receive therapy, or this patient may be a no-go. And you could think that if neuroprotection delivery
to the penumbra is able to be done, that these patients may be offered therapy which they currently are not. And even this patient that's offered therapy, might then leave with a moderate disability, may have a much better functional
independence upon discharge. When one queries active clinical trials, there's nothing on intra arterial delivery of a potent neuroprotection following thrombectomy. These are two trials, an IV infusion, peripheral infusion, and one on just verapamil to prevent vasospasm.
So there's a large large need for delivery of a potent neuroprotection following thrombectomy. In conclusion, we're in the door now where we can do mechanical thrombectomy for intracranial thrombus, obviously concomitant to what we do in the carotid bifurcation is rare,
but those patients do present. There's still a large number of patients that are still not actively treated, some estimate 50 to 60% with typical mechanical thrombectomy. And one can speculate how ideally delivery of a potent neuroprotection to this area could
help treat 50, 60% of patients that are being denied currently, and even those that are being treated could have a much better recovery. I'd like to thank you, Frank for the meeting, and to Jackie for the great organization.
- I'm going to be speaking about indirect access sites for access intervention. I'm going to be focusing on the transjugular approach. So access interventions, typically we perform them through a direct puncture of the fistula. Sometimes you place two introducers. There are some disadvantages to the direct approach.
The crossing catheters technique that we generally use for declots is awkward and cumbersome. The introducers can obstruct flow, there's dead space behind the introducers that can trap clot, and there's radiation exposure or the direct exposure
or scatter radiation from hands near the field. Admit it, we've all had access-site complications, suture-site necrosis and infection, as well as pseudoaneurysms. There's also prolonged procedure time related to needing to obtain hemostasis
in the high-pressure segment. There are also problems particularly to immature fistulas, such as hematoma formation, spasm at the introducer site causing pseudo-stenosis, decreased flow, and fistula thrombosis. Now, the good news is that we do have options
for alternative access sites. I'm sure many of you here use arterial access for immature fistulas in particular. Brachial access can be used to, this can be used for diagnostic or therapeutic purposes. We can also utilize radial or ulnar access.
Rarely, femoral access is used, as we saw in the last presentation. But there's also pendula venous access sites. You can sometimes, as a fortuitous tributary, what I call a target of opportunity, and also, the internal jugular vein.
Now, the transjugular approach was first reported in 1998. It does have some definite advantages over direct puncture technique. You can avoid the cumbersome access, you can keep your hands away from the beam, and there's no dead space as compared
to crossing sheaths for your declot. And if the intervention is unsuccessful, you can convert your IJ access to a catheter if you already have a wire in it. There are some technical challenges associated with this technique.
You do have to overcome the valves. It can be difficult to access the cephalic vein, but you can get around this by using a snare. And there's possibly a risk of IJ thrombosis if you're using large introducers. When to use this technique?
Well, when direct puncture's going to be difficult or cumbersome, when there's a short cannulation segment, when it's an extensively stented access, and when there's inflow pathology requiring a retrograde approach or arterial empathalogy, and it's a good option for clotted access.
The technique, micropuncture access of the jugular vein, ipsilateral or contralateral, place a sheath, and an important thing to use is a reverse-curve catheter, followed by glidewire. So here, we've cannulated the jugular vein going down,
glidewire out into the arm. If you're unable to cross into the cephalic vein, you can use that snare technique. And you can get a long, stable access in this way. It's been reported about, there's about 10 publications on transjugular approach, seven retrospective studies.
There's a large study that's reported thrombectomy. Also a large study looking at immature fistulas. Smaller studies looking at dysfunctional access and pseudoaneurysms. Two case reports, one review article, but there's of course no randomized studies.
There's a recent study from this year from Ferral and Alonzo. This was a retrospective study. Over two years they performed 30 transjugular AV access interventions. This accounted for 5% of their access experience
and this series was all fistulance. Indications for the procedure, 43% were declots, 43% were arterial and fistual pathology, there were two immature fistulas and two bleeding pseudoaneurysms. The access approach was 29 for ipsilateral,
only one contralateral. The results, 97% technical success, a snare was required in 4 cases, a catheter was inserted in two of the cases. There were no episodes of jugular vein thrombosis. In the remaining time, I'd like to show
a couple of case studies. Again, from Ferral and Alonzo. This is a case of an immature fistula. This was a partially occluded, immature left upper arm fistula. The initial fistulagram shows outflow stenosis
with a multiple stenosis in thrombus, and there's an arterial in stenosis that's distal to the access point, so you're not going to be able to treat that. They performed four millimeter angioplasty. Follow-up fistulagram shows a small, but patent vein
and the arterial end could not be treated. They brought the patient back in two weeks for a staged transjugular approach. And you can see the jugular catheter coming down. The vein diameter's improved, but there's still the untreated arterial end stenosis,
which is easily treated through the jugular approach. This is a study from, a case from Dr. Rabellino, ruptured pseudoaneurysm. This is a basilic transposition with a ruptured pseudoaneurysm at an infiltration site. Pretty ugly arm, swollen, skin necrosis.
I don't think we want to be sticking that arm. They initially went with a femoral approach for the fistulagram, demonstrated the pseudoaneurysm. As you can see here, tandem outflow stenoses. Coming up from below with the femoral artery diagnostic catheter.
Down and into the arm through the jugular approach. And here, you can see the venous outflow after angioplasty, covered stent deployed through the jugular access. So in summary, the transjugular approach is a useful but underutilized technique. The advantages include single-puncture intervention,
does not involve the outflow vein directly, simplified hemostasis, it's a low pressure system. It does have the advantage that you can use large introducers, there's less radiation for the operator, and you can convert to a catheter easily if needed. It is a useful technique for fistula maturation,
thrombectomy, and access maintenance. I say go for the jugular.
- Good morning. I'd like to thank Dr. Veith and Symposium for my opportunity to speak. I have no disclosures. So the in Endovascular Surgery, there is decrease open surgical bypass. But, bypass is still required for many patients with PAD.
Autologous vein is preferred for increase patency lower infection rate. And, Traditional Open Vein Harvest does require lengthy incisions. In 1996 cardiac surgery reported Endoscopic Vein Harvest. So the early prospective randomized trial
in the cardiac literature, did report wound complications from Open Vein Harvest to be as high as 19-20%, and decreased down to 4% with Endoscopic Vein Harvest. Lopes et al, initially, reported increase risk of 12-18 month graft failure and increased three year mortality.
But, there were many small studies that show no effect on patency and decreased wound complications. So, in 2005, Endoscopic Vein Harvest was recommended as standard of care in cardiac surgical patients. So what about our field? The advantages of Open Vein Harvest,
we all know how to do it. There's no learning curve. It's performed under direct visualization. Side branches are ligated with suture and divided sharply. Long term patency of the bypass is established. Disadvantages of the Open Vein Harvest,
large wound or many skip wounds has an increased morbidity. PAD patients have an increased risk for wound complications compared to the cardiac patients as high as 22-44%. The poor healing can be due to ischemia, diabetes, renal failure, and other comorbid conditions.
These can include hematoma, dehiscense, infection, and increased length of stay. So the advantages of Endoscopic Vein Harvest, is that there's no long incisions, they can be performed via one or two small incisions. Limiting the size of an incision
decreases wound complications. It's the standard of care in cardiac surgery, and there's an overall lower morbidity. The disadvantages of is that there's a learning curve. Electro-cautery is used to divide the branches, you need longer vein compared to cardiac surgery.
There's concern about inferior primary patency, and there are variable wound complications reported. So recent PAD data, there, in 2014, a review of the Society of Vascular Surgery registry, of 5000 patients, showed that continuous Open Vein Harvest
was performed 49% of the time and a Endo Vein Harvest about 13% of the time. The primary patency was 70%, for Continuous versus just under 59% for Endoscopic, and that was significant. Endoscopic Vein Harvest was found to be an independent risk factor for a lower one year
primary patency, in the study. And, the length of stay due to wounds was not significantly different. So, systematic review of Endoscopic Vein Harvest data in the lower extremity bypass from '96 to 2013 did show that this technique may reduce
primary patency with no change in wound complications. Reasons for decreased primary patency, inexperienced operator, increased electrocautery injury to the vein. Increase in vein manipulation, you can't do the no touch technique,
like you could do with an Open Harvest. You need a longer conduit. So, I do believe there's a roll for this, in the vascular surgeon's armamentarium. I would recommend, how I use it in my practices is, I'm fairly inexperienced with Endoscopic Vein Harvest,
so I do work with the cardiac PA's. With increased percutaneous procedures, my practice has seen decreased Saphenous Vein Bypasses, so, I've less volume to master the technique. If the PA is not available, or the conduit is small, I recommend an Open Vein Harvest.
The PA can decrease the labor required during these cases. So, it's sometimes nice to have help with these long cases. Close surveillance follow up with Non-Invasive Arterial Imaging is mandatory every three months for the first year at least. Thank you.
- Thank you Mr. Chairman, good morning ladies and gentlemen. So that was a great setting of the stage for understanding that we need to prevent reinterventions of course. So we looked at the data from the DREAM trial. We're all aware that we can try
to predict secondary interventions using preoperative CT parameters of EVAR patients. This is from the EVAR one trial, from Thomas Wyss. We can look at the aortic neck, greater angulation and more calcification.
And the common iliac artery, thrombus or tortuosity, are all features that are associated with the likelihood of reinterventions. We also know that we can use postoperative CT scans to predict reinterventions. But, as a matter of fact, of course,
secondary sac growth is a reason for reintervention, so that is really too late to predict it. There are a lot of reinterventions. This is from our long term analysis from DREAM, and as you can see the freedom, survival freedom of reinterventions in the endovascular repair group
is around 62% at 12 years. So one in three patients do get confronted with some sort of reintervention. Now what can be predicted? We thought that the proximal neck reinterventions would possibly be predicted
by type 1a Endoleaks and migration and iliac thrombosis by configurational changes, stenosis and kinks. So the hypothesis was: The increase of the neck diameter predicts proximal type 1 Endoleak and migration, not farfetched.
And aneurysm shrinkage maybe predicts iliac limb occlusion. Now in the DREAM trial, we had a pretty solid follow-up and all patients had CT scans for the first 24 months, so the idea was really to use
those case record forms to try to predict the longer term reinterventions after four, five, six years. These are all the measurements that we had. For this little study, and it is preliminary analysis now,
but I will be presenting the maximal neck diameter at the proximal anastomosis. The aneurysm diameter, the sac diameter, and the length of the remaining sac after EVAR. Baseline characteristics. And these are the re-interventions.
For any indications, we had 143 secondary interventions. 99 of those were following EVAR in 54 patients. By further breaking it down, we found 18 reinterventions for proximal neck complications, and 19 reinterventions
for thrombo-occlusive limb complications. So those are the complications we are trying to predict. So when you put everything in a graph, like the graphs from the EVAR 1 trial, you get these curves,
and this is the neck diameter in patients without neck reintervention, zero, one month, six months, 12, 18, and 24 months. There's a general increase of the diameter that we know.
But notice it, there are a lot of patients that have an increase here, and never had any reintervention. We had a couple of reinterventions in the long run, and all of these spaces seem to be staying relatively stable,
so that's not helping much. This is the same information for the aortic length reinterventions. So statistical analysis of these amounts of data and longitudinal measures is not that easy. So here we are looking at
the neck diameters compared for all patients with 12 month full follow-up, 18 and 24. You see there's really nothing happening. The only thing is that we found the sac diameter after EVAR seems to be decreasing more for patients who have had reinterventions
at their iliac limbs for thrombo-occlusive disease. That is something we recognize from the literature, and especially from these stent grafts in the early 2000s. So conclusion, Mr. Chairman, ladies and gentlemen, CT changes in the first two months after EVAR
predict not a lot. Neck diameter was not predictive for neck-reinterventions. Sac diameter seems to be associated with iliac limb reinterventions, and aneurysm length was not predictive
of iliac limb reinterventions. Thank you very much.
- Thank you (mumbles) and thank you Dr. Veith for the kind invitation to participate in this amazing meeting. This is work from Hamburg mainly and we all know that TEVAR is the first endovascular treatment of choice but a third of our patients will fail to remodel and that's due to the consistent and persistent
flow in the false lumen over the re-entrance in the thoracoabdominal aorta. Therefore it makes sense to try to divide the compartments of the aorta and try to occlude flow in the false lumen and this can be tried by several means as coils, plug and glue
but also iliac occluders but they all have the disadvantage that they don't get over 24 mm which is usually not enough to occlude the false lumen. Therefore my colleague, Tilo Kolbel came up with this first idea with using
a pre-bulged stent graft at the midportion which after ballooning disrupts the dissection membrane and opposes the outer wall and therefore occludes backflow into the aneurysm sac in the thoracic segment, but the most convenient
and easy to use tool is the candy-plug which is a double tapered endograft with a midsegment that is 18 mm and once implanted in the false lumen at the level of the supraceliac aorta it occludes the backflow in the false lumen in the thoracic aorta
and we have seen very good remodeling with this approach. You see here a patient who completely regressed over three years and it also answers the question how it behaves with respect to true and false lumen. The true lumen always wins and because once
the false lumen thrombosis and the true lumen also has the arterial pressure it does prevail. These are the results from Hamburg with an experience of 33 patients and also the international experience with the CMD device that has been implanted in more than 20 cases worldwide
and we can see that the interprocedural technical success is extremely high, 100% with no irrelevant complications and also a complete false lumen that is very high, up to 95%. This is the evolvement of the candy-plug
over the years. It started as a surgeon modified graft just making a tie around one of the stents evolving to a CMD and then the last generation candy-plug II that came up 2017 and the difference, or the new aspect
of the candy-plug II is that it has a sleeve inside and therefore you can retrieve the dilator without having to put another central occluder or a plug in the central portion. Therefore when the dilator is outside of the sleeve the backflow occludes the sleeve
and you don't have to do anything else, but you have to be careful not to dislodge the whole stent graft while retrieving the dilator. This is a case of a patient with post (mumbles) dissection.
This is the technique of how we do it, access to the false lumen and deployment of the stent graft in the false lumen next to the true lumen stent graft being conscious of the fact that you don't go below the edge of the true lumen endograft
to avoid (mumbles) and the final angiography showing no backflow in the aneurysm. This is how we measure and it's quite simple. You just need about a centimeter in the supraceliac aorta where it's not massively dilated and then you just do an over-sizing
in the false lumen according to the Croissant technique as Ste-phan He-lo-sa has described by 10 to 30% and what is very important is that in these cases you don't burn any bridges. You can still have a good treatment
of the thoracic component and come back and do the fenestrated branch repair for the thoracoabdominal aorta if you have to. Thank you very much for your attention. (applause)
- Thank you to the moderators, thank you to Dr. Veith for having me. Let's go! So my topic is to kind of introduce the ATTRACT trial, and to talk a little bit about how it affected, at least my practice, when it comes to patients with acute DVT.
I'm on the scientific advisory board for a company that makes IVC filters, and I also advise to BTG, so you guys can ask me about it later if you want. So let's talk about a case. A 50-year-old man presents
from an outside hospital to our center with left lower extremity swelling. And this is what somebody looks like upon presentation. And pulses, motor function, and sensation are actually normal at this point.
And he says to us, "Well, symptoms started "three days ago. "They're about the same since they started," despite being on anticoagulation. And he said, "Listen guys, in the other hospital, "they wouldn't do anything.
"And I want a procedure because I want the clot "out of me." so he's found to have this common femoral vein DVT. And the question is should endovascular clot removal be performed for this patient?
Well the ATTRACT trial set off to try and prevent a complication you obviously all know about, called the post-thrombotic syndrome, which is a spectrum from sort of mild discomfort and a little bit of dyspigmentation and up
to venous ulcerations and quite a lot of morbidity. And in ATTRACT, patients with proximal DVT were randomized to anticoagulation alone or in combination with pharma mechanical catheter-directed thrombolysis.
And the reason I put proximal in quotes is because it wasn't only common sort of femoral vein clots, but also femoral vein clots including the distal femoral vein were included eventually. And so patients with clots were recruited,
and as I said, they were randomized to those two treatments. And what this here shows you is the division into the two groups. Now I know this is a little small, but I'll try and kind of highlight a few things
that are relevant to this talk. So if you just read the abstract of the ATTRACT trial published last year in the New England Journal of Medicine, it'll seem to you that the study was a negative study.
The conclusion and the abstract is basically that post-thrombotic syndrome was not prevented by performing these procedures. Definitely post-thrombotic syndrome is still frequent despite treatment. But there was a signal for less severe
post-thrombotic syndrome and for more bleeding. And I was hoping to bring you all, there's an upcoming publication in circulation, hopefully it'll be online, I guess, over the weekend or early next week, talking specifically about patients
with proximal DVT. But you know, I'm speaking now without those slides. So what I can basically show you here, that at 24 months, unfortunately, there was no, well not unfortunately,
but the fact is, it did cross the significance and it was not significant from that standpoint. And what you can see here, is sort of a continuous metric of post-thrombotic syndrome. And here there was a little bit of an advantage
towards reduction of severe post-thrombotic syndrome with the procedure. What it also shows you here in this rectangle, is that were more bleeds, obviously, in the patients who received the more aggressive therapy.
One thing that people don't always talk about is that we treat our patients for two reasons, right? We want to prevent post-thrombotic syndrome but obviously, we want to help them acutely. And so what the study also showed,
was that acute symptoms resolved more quickly in patients who received the more aggressive therapy as opposed to those who did not. Again, at the price of more bleeding. So what happened to this patient? Well you know,
he presented on a Friday, obviously. So we kind of said, "Yeah, we probably are able "to try and do something for you, "but let's wait until Monday." And by Monday, his leg looked like this, with sort of a little bit of bedrest
and continued anticoagulation. So at the end of the day, no procedure was done for this particular patient. What are my take home messages, for whatever that's worth? Well I think intervention for DVT
has several acute indications. Restore arterial flow when phlegmasia is the problem, and reduce acute symptoms. I think intervention for common femoral and more proximal DVT likely does have long-term benefit, and again, just be
on the lookout for that circ paper that's coming out. Intervention for femoral DVT, so more distal DVT, in my opinion, is rarely indicated. And in the absence of phlegmasia, for me, thigh swelling is a good marker for a need
for a procedure, and I owe Dr. Bob Schainfeld that little tidbit. So thank you very much for listening.
- Thank you, Larry, thank you, Tony. Nice to be known as a fixture. I have no relevant disclosures, except that I have a trophy. And that's important, but also that Prabir Roy-Chaudhury, who's in this picture, was the genesis of some of the thoughts that I'm going to deliver here about predicting renal failure,
so I do want to credit him with bringing that to the vascular access space. You know, following on Soren's talk about access guidelines, we're dealing with pretty old guidelines, but if you look at the 2006 version, you know, just the height--
The things that a surgeon might read in his office. CKD four, patients there, you want a timely referral, you want them evaluated for placement of permanent access. The term "if necessary" is included in those guidelines, that's sometimes forgotten about.
And, of course, veins should be protected. We already heard a little bit about that, and so out our hospital, with our new dialysis patients, we usually try to butcher both antecubital veins at the same time. And then, before we send them to surgery
after they've been vein-marked, we use that vein to put in their preoperative IV, so that's our vascular access management program at Christiana Care. - [Male Speaker] That's why we mark it for you, Teddy. (laughing)
- So, you know, the other guideline is patients should have a functional permanent access at the initiation of dialysis therapy, and that means we need a crystal ball. How do we know this? A fistula should be placed at least six months
before anticipated start of dialysis, or a graft three to six weeks. Anybody who tells you they actually know that is lying, you can't tell, there's no validated means of predicting this. You hear clinical judgment, you can look at
all sorts of things. You cannot really make that projection. Now there is one interesting study by Tangri, and this is what Premier brought to our attention last year at CIDA, where this Canadian researcher and his team developed a model for predicting
progression of chronic kidney disease, not specifically for access purposes, but for others. They looked at a large number of patients in Canada, followed them through chronic kidney disease to ESRD, and they came up with a model. If you look at a simple model that uses age, sex,
estimated GFR from MDRD equation and albuminuria to predict when that patient might develop end stage renal disease, and there's now nice calculators. This is a wonderful thing, I keep it on my phone, this Qx Calculate, I would recommend you do the same,
and you can put those answers to the questions, in this app, and it'll give you the answer you're looking for. So for instance, here's a case, a 75-year-old woman, CKD stage four, her creatinine's 2.7, not very impressive,
eGFR's 18. Her urine protein is 1200 milligrams per gram, that's important, this is kind of one of the major variables that impacts on this. So she's referred appropriately at that stage to a surgeon for arteriovenous access,
and he finds that she really has no veins that he feels are suitable for a fistula, so an appropriate referral was made. Now at that time, if you'd put her into this equation with those variables, 1200, female, 75-year-old, 18 GFR, at two years, her risk of ESRD is about 30%,
and at five years about 66%, 67%. So, you know, how do you use those numbers in deciding if she needs an access? Well, you might say... A rational person might say perhaps that patient should get a fistula,
or at least be put in line for it. Well, this well-intentioned surgeon providing customer service put in a graft, which then ended up with some steal requiring a DRIL, which then still had steal, required banding, and then a few months, a year later
was thrombosed and abandoned because she didn't need it. And I saw her for the first time in October 2018, at which time her creatinine is up to 3.6, her eGFR's down to 12, her protein is a little higher, 2600, so now she has a two-year risk of 62%, and a five-year risk of 95%,
considerably more than when this ill-advised craft was created. So what do you do with this patient now? I don't have the answer to that, but you can use this information at least to help flavor your thought process,
and what if you could bend the curve? What if you treated this patient appropriately with ACE inhibitors and other methods to get the protein down? Well, you can almost half her two-year risk of renal failure with medical management.
So these considerations I think are important to the team, surgeon, nurses, nephrologists, etc., who are planning that vascular access with the patient. When to do and what to do. And then, you know, it's kind of old-fashioned to look at the trajectory.
We used to look at one over creatinine, we can look at eGFR now, and she's on a trajectory that looks suspicious for progression, so you can factor that into your thought process as well. And then I think this is the other very important concept, I think I've spoken about this here before,
is that there's no absolute need for dialysis unless you do bilateral nephrectomies. Patients can be managed medically for quite a while, and the manifestations of uremia dealt with quite safely and effectively, and you can see that over the years, the number of patients
in this top brown pattern that have been started on dialysis with a GFR of greater than 15 has fallen, or at least, stopped rising because we've recognized that there's no advantage, and there may be disadvantages to starting patients too early.
So if your nephrologist is telling I've got to start this patient now because he or she needs dialysis, unless they had bilateral nephrectomies that may or may not be true. Another case,
64-year-old male, CKD stage four, creatinine about four, eGFR 15, 800 milligrams of proteinuria, referred to a vascular access surgeon for AV access. Interesting note, previous central lines, or AICD, healthy guy otherwise.
So in April 2017 he had a left wrist fistula done, I think that was a very appropriate referral and a very appropriate operation by this surgeon. At that time his two-year risk was 49, 50%, his five-year risk 88%. It's a pretty good idea, I think, to get a wrist fistula
in that patient. Once again, this is not validated for that purpose. I can't point you to a study that says by using this you can make well-informed predictions about when to do vascular access, but I do think it helps to flavor the judgment on this.
Also, I saw him for the first time last month, and his left arm is like this. Amazing, that has never had a catheter or anything, so I did his central venogram, and this is his anatomy. I could find absolutely no evidence of a connection between the left subclavian and the superior vena cava,
I couldn't cross it. Incidentally, this was done with less than 20 CCs of dye of trying to open this occlusion or find a way through, which was unsuccessful. You can see all the edema in his arm. So what do you do with this guy now?
Well, up, go back. Here's his trajectory of CKD four from the time his fistula is done to the time I'm seeing him now, he's been pretty flat. And his proteinuria's actually dropped
with medical management. He's only got 103 milligrams per gram of proteinuria now, and his two-year risk is now 23%, his five-year risk is 56%, so I said back to the surgeon we ligate this damn thing, because we can't really do much to fix it,
and we're going to wait and see when it's closer to time to needing dialysis. I'm not going to subject this guy to a right-arm fistula with that trajectory of renal disease over the past two years. So combining that trajectory with these predictive numbers,
and improved medical care for proteinuria I think is a good strategy. So what do you do, you're weighing factors for timing too early, you've got a burden of fistula failure, interventions you need to use to maintain costs, morbidity, complications,
steal, neuropathy that you could avoid versus too late and disadvantages of initiating hemodialysis without a permanent access. And lastly, I'm going to just finish with some blasphemy. I think the risk of starting dialysis with a catheter is vastly overstated.
If you look at old data and patient selection issues, and catheter maintenance issues, I think... It's not such an unreasonable thing to start a patient with a catheter. We do it all the time and they usually live.
And even CMS gives us a 90-day grace period on our QIP penalties, so... If you establish a surgeon and access plan, I think you're good to go. So who monitors access maturation? I don't know, somebody who knows what they're doing.
If you look at all the people involved, I know some of these individuals who are absolute crackerjack experts, and some are clueless. It has nothing to do with their age, their gender, their training, their field. It's just a matter of whether they understand
what makes a good fistula. You don't have to be a genius, you just can't be clueless. This is not a mature usable fistula, I know that when I see it. Thank you.
- Mr. Chairman, ladies and gentlemen, good morning. I'd like to thank Dr. Veith for the opportunity to present at this great meeting. I have nothing to disclose. Since Dr. DeBakey published the first paper 60 years ago, the surgical importance of deep femoral artery has been well investigated and documented.
It can be used as a reliable inflow for low extremity bypass in certain circumstances. To revascularize the disease, the deep femoral artery can improve rest pain, prevent or delay the amputation, and help to heal amputation stump.
So, in this slide, the group patient that they used deep femoral artery as a inflow for infrainguinal bypass. And 10-year limb salvage was achieved in over 90% of patients. So, different techniques and configurations
of deep femoral artery angioplasty have been well described, and we've been using this in a daily basis. So, there's really not much new to discuss about this. Next couple minutes, I'd like to focus on endovascular invention 'cause I lot I think is still unclear.
Dr. Bath did a systemic review, which included 20 articles. Nearly total 900 limbs were treated with balloon angioplasty with or without the stenting. At two years, the primary patency was greater than 70%. And as you can see here, limb salvage at two years, close to, or is over 98% with very low re-intervention rate.
So, those great outcomes was based on combined common femoral and deep femoral intervention. So what about isolated deep femoral artery percutaneous intervention? Does that work or not? So, this study include 15 patient
who were high risk to have open surgery, underwent isolated percutaneous deep femoral artery intervention. As you can see, at three years, limb salvage was greater than 95%. The study also showed isolated percutaneous transluminal
angioplasty of deep femoral artery can convert ischemic rest pain to claudication. It can also help heal the stump wound to prevent hip disarticulation. Here's one of my patient. As you can see, tes-tee-lee-shun with near
or total occlusion of proximal deep femoral artery presented with extreme low-extremity rest pain. We did a balloon angioplasty. And her ABI was increased from 0.8 to 0.53, and rest pain disappeared. Another patient transferred from outside the facility
was not healing stump wound on the left side with significant disease as you can see based on the angiogram. We did a hybrid procedure including stenting of the iliac artery and the open angioplasty of common femoral artery and the profunda femoral artery.
Significantly improved the perfusion to the stump and healed wound. The indications for isolated or combined deep femoral artery revascularization. For those patient presented with disabling claudication or rest pain with a proximal
or treatable deep femoral artery stenosis greater than 50% if their SFA or femoral popliteal artery disease is unsuitable for open or endovascular treatment, they're a high risk for open surgery. And had the previous history of multiple groin exploration, groin wound complications with seroma or a fungal infection
or had a muscle flap coverage, et cetera. And that this patient should go to have intervascular intervention. Or patient had a failed femoral pop or femoral-distal bypass like this patient had, and we should treat this patient.
So in summary, open profundaplasty remains the gold standard treatment. Isolated endovascular deep femoral artery intervention is sufficient for rest pain. May not be good enough for major wound healing, but it will help heal the amputation stump
to prevent hip disarticulation. Thank you for much for your attention.
- Good morning, thank you, Dr. Veith, for the invitation. My disclosures. So, renal artery anomalies, fairly rare. Renal ectopia and fusion, leading to horseshoe kidneys or pelvic kidneys, are fairly rare, in less than one percent of the population. Renal transplants, that is patients with existing
renal transplants who develop aneurysms, clearly these are patients who are 10 to 20 or more years beyond their initial transplantation, or maybe an increasing number of patients that are developing aneurysms and are treated. All of these involve a renal artery origin that is
near the aortic bifurcation or into the iliac arteries, making potential repair options limited. So this is a personal, clinical series, over an eight year span, when I was at the University of South Florida & Tampa, that's 18 patients, nine renal transplants, six congenital
pelvic kidneys, three horseshoe kidneys, with varied aorto-iliac aneurysmal pathologies, it leaves half of these patients have iliac artery pathologies on top of their aortic aneurysms, or in place of the making repair options fairly difficult. Over half of the patients had renal insufficiency
and renal protective maneuvers were used in all patients in this trial with those measures listed on the slide. All of these were elective cases, all were technically successful, with a fair amount of followup afterward. The reconstruction priorities or goals of the operation are to maintain blood flow to that atypical kidney,
except in circumstances where there were multiple renal arteries, and then a small accessory renal artery would be covered with a potential endovascular solution, and to exclude the aneurysms with adequate fixation lengths. So, in this experience, we were able, I was able to treat eight of the 18 patients with a fairly straightforward
endovascular solution, aorto-biiliac or aorto-aortic endografts. There were four patients all requiring open reconstructions without any obvious endovascular or hybrid options, but I'd like to focus on these hybrid options, several of these, an endohybrid approach using aorto-iliac
endografts, cross femoral bypass in some form of iliac embolization with an attempt to try to maintain flow to hypogastric arteries and maintain antegrade flow into that pelvic atypical renal artery, and a open hybrid approach where a renal artery can be transposed, and endografting a solution can be utilized.
The overall outcomes, fairly poor survival of these patients with a 50% survival at approximately two years, but there were no aortic related mortalities, all the renal artery reconstructions were patented last followup by Duplex or CT imaging. No aneurysms ruptures or aortic reinterventions or open
conversions were needed. So, focus specifically in a treatment algorithm, here in this complex group of patients, I think if the atypical renal artery comes off distal aorta, you have several treatment options. Most of these are going to be open, but if it is a small
accessory with multiple renal arteries, such as in certain cases of horseshoe kidneys, you may be able to get away with an endovascular approach with coverage of those small accessory arteries, an open hybrid approach which we utilized in a single case in the series with open transposition through a limited
incision from the distal aorta down to the distal iliac, and then actually a fenestrated endovascular repair of his complex aneurysm. Finally, an open approach, where direct aorto-ilio-femoral reconstruction with a bypass and reimplantation of that renal artery was done,
but in the patients with atypical renals off the iliac segment, I think you utilizing these endohybrid options can come up with some creative solutions, and utilize, if there is some common iliac occlusive disease or aneurysmal disease, you can maintain antegrade flow into these renal arteries from the pelvis
and utilize cross femoral bypass and contralateral occlusions. So, good options with AUIs, with an endohybrid approach in these difficult patients. Thank you.
- Thank you very much, so my disclosures, I'm one of the co-PIs for national registry for ANARI. And clearly venous clot is different, requires different solutions for the arterial system. So this is a device that was built ground up to work in the venous system. And here's a case presentation of a 53 year old male,
with a history of spondylolisthesis had a lumbar inner body fusion, he had an anterior approach and corpectomy with application of an inner body cage. And you can see these devices here. And notably he had application of local bone graft and bone powder
and this is part of what happened to this patient. About seven days later he came in with significant left leg swelling and venous duplex showed clot right here, and this extended all the way down to the tibial vessels. And if you look at the CT
you can see extravasation of that bone powder and material obstructing the left iliac vein. And had severe leg swelling so the orthopedic people didn't want us to use TPA in this patient so we considered a mechanical solution. And so at this day and age I think goals of intervention
should be to maximize clot removal of course and minimize bleeding risk and reduce the treatment or infusion time and go to single session therapy whenever possible. Our ICUs are full all the time and so putting a lytic patient in there
reduces our ability to get other patients in. (mouse clicks So this is the ClotTriever thrombectomy device. It has a sheath that is a 13 French sheath and they're developing a 16 French, that opens up with a funnel
after it's inserted into the poplitiel. So the funnel is in the lower femoral vein and this helps funnel clot in when it's pulled down. The catheter has this coring element that abuts the vein wall and carves the thrombus off in a collecting bag
that extends up above to allow the thrombus to go into the bag as you pull it down. So you access the popliteal vein, cross the thrombosed segments with standard techniques and you need to then put an exchange length wire up into the SVC
or even out into the subclavian vein for stability. And then the catheter's inserted above the clot and is gradually pulled down, sort of milking that stuff off of the wall and into the bag that is then taken down to the funnel and out of the leg.
So this is the patient we had, we had thrombus in the femoral and up into the IVC. Extensive, you can see the hardware here. And it was very obstructed right at that segment where it was, had the bone material pushing on the vein it was quite difficult to get through there
but finally we did and we ballooned that to open a channel up large enough to accommodate ClotTriever catheter. We then did multiple passes and we extracted a large amount of thrombus. Some looking like typically acute stuff
and then some more dense material that may have been a few days worth of build up on the wall there. We then stinted with an 18 by 90 across the obstructed segment and this was our completion run.
It's not perfect but it looks like a pretty good channel going through. This is the hardware not obstruction at that level. Hospital course, the patient had significant improvement in their swelling by post-op day one. Was discharged on compression and anti-coagulation.
He returned about two months ago for his three month follow-up and really had very minimal symptoms in the left leg. Venous duplex showed that the left common femoral was partially compressible but did have phasic flow and the stent appeared to be open through it's course.
So of course this is an anecdote, this is early in the experience with this catheter. There have been numerous improvements made to ease the use of it and do it in fewer steps. And so we're starting a ClotTriever outcomes registry
to enroll up to 500 patients to begin to define outcomes with this device. It does offer the promise of single session therapy without lytic administration and we'll see how it performs and which patients it works best in through the registry.
Thank you very much.
- Thank you for introduction. Thanks to Frank Veith for the kind invitation to present here our really primarily single-center experience on this new technique. This is my disclosure. So what you really want
in the thromboembolic acute events is a quick flow restoration, avoid lytic therapies, and reduce the risk of bleeding. And this can be achieved by surgery. However, causal directed local thrombolysis
is much less invasive and also give us a panoramic view and topographic view that is very useful in these cases. But it takes time and is statistically implied
and increases risk of bleeding. So theoretically percutaneous thrombectomy can accomplish all these tasks including a shorter hospital stay. So among the percutaneous thrombectomy devices the Indigo System is based on a really simple
aspiration mechanism and it has shown high success in ischemic stroke. This is one of my first cases with the Indigo System using a 5 MAX needle intervention
adapted to this condition. And it's very easy to understand how is fast and effective this approach to treat intraprocedural distal embolization avoiding potential dramatic clinical consequences, especially in cases like this,
the only one foot vessel. This is also confirmed by this technical note published in 2015 from an Italian group. More recently, other papers came up. This, for example, tell us that
there has been 85% below-the-knee primary endpoint achievement and 54% in above-the-knee lesions. The TIMI score after VAT significantly higher for BTK lesions and for ATK lesions
a necessity of a concomitant endovascular therapy. And James Benenati has already told us the results of the PRISM trials. Looking into our case data very quickly and very superficially we can summarize that we had 78% full revascularization.
In 42% of cases, we did not perform any lytic therapy or very short lytic therapy within three hours. And in 36% a long lytic therapy was necessary, however within 24 hours. We had also 22% failure
with three surgery necessary and one amputation. I must say that among this group of patients, twenty patients, there were also patients like this with extended thrombosis from the groin to the ankle
and through an antegrade approach, that I strongly recommend whenever possible, we were able to lower the aspiration of the clots also in the vessel, in the tibial vessels, leaving only this region, thrombosis
needed for additional three hour infusion of TPA achieving at the end a beautiful result and the patient was discharged a day after. However not every case had similar brilliant result. This patient went to surgery and he went eventually to amputation.
Why this? And why VAT perform better in BTK than in ATK? Just hypotheses. For ATK we can have unknown underlying chronic pathology. And the mismatch between the vessel and the catheter can be a problem.
In BTK, the thrombus is usually soft and short because it is an acute iatrogenic event. Most importantly is the thrombotic load. If it is light, no short, no lytic or short lytic therapy is necessary. Say if heavy, a longer lytic therapy and a failure,
regardless of the location of the thrombosis, must be expected. So moving to the other topic, venous occlusive thrombosis. This is a paper from a German group. The most exciting, a high success rate
without any adjunctive therapy and nine vessels half of them prosthetic branch. The only caution is about the excessive blood loss as a main potential complication to be checked during and after the procedure. This is a case at my cath lab.
An acute aortic renal thrombosis after a open repair. We were able to find the proximate thrombosis in this flush occlusion to aspirate close to fix the distal stenosis
and the distal stenosis here and to obtain two-thirds of the kidney parenchyma on both sides. And this is another patient presenting with acute mesenteric ischemia from vein thrombosis.
This device can be used also transsympatically. We were able to aspirate thrombi but after initial improvement, the patient condition worsened overnight. And the CT scan showed us a re-thrombosis of the vein. Probably we need to learn more
in the management of these patients especially under the pharmacology point of view. And this is a rapid overview on our out-of-lower-limb case series. We had good results in reimplanted renal artery, renal artery, and the pulmonary artery as well.
But poor results in brachial artery, fistula, and superior mesenteric vein. So in conclusion, this technology is an option for quick thromboembolic treatment. It's very effective for BTK intraprocedural embolic events.
The main advantage is a speeding up the blood flow and reestablishing without prolonged thrombolysis or reducing the dosage of the thrombolysis. Completely cleaning up extensive thromobosed vessels is impossible without local lytic therapies. This must be said very clearly.
Indigo technology is promising and effective for treatment of acute renovisceral artery occlusion and sub massive pulmonary embolism. Thank you for your attention. I apologize for not being able to stay for the discussion
because I have a flight in a few hours. Thank you very much.
- 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, I'm going to probably echo many of the themes that Gary just touched upon here. These are my disclosures. So, if we look at the CHEST guidelines on who should get pharmacomechanical techniques, it is very very very sobering, and I apologize if the previous speakers have shown this slide,
but essentially, what's right now being disseminated to the American College of CHEST Physicians is that nobody should get catheter-directed thrombolysis, the concept of pharmacomechanical technique should really only reserved as a last-ditch effort if nothing else works, if you happen to have somebody
with extraordinary expertise in your institution, it could not be more of a damning recommendation for what I'm about to talk to you about for the next eight or nine minutes or so. So, then the question is, what is the rationale? What are we talking about here?
And again, I'm going to say that Gary and I, I think are sort of kindred spirits in recognizing that we really do need to mature this concept of the catheter-based technique for pulmonary embolism. So, I'm going to put out a hypothetical question, what if there was a single session/single device therapy
for acute PE, Gary showed one, that could avoid high dose lytics, avoid an overnight infusion, acutely on the table lower the PA pressure, acutely improve the function of the right ventricle, rapidly remove, you know, by angiography,
thrombus and clot from the pulmonary artery, and it was extremely safe, what if we had that? Would that change practice? And I would respectfully say, yes it would. And then what if this concept has already been realized, and we're actually using this across the world
for STEMI, for stroke, for acute DVT, and so why not acute pulmonary embolism? What is limiting our ability to perform single session, rapid thrombus removal and
patient stabilization on the table? Gary showed this slide, there's this whole litany of different devices, and I would argue none of them is exactly perfect yet, but I'm going to try and sort of walk you through what has been developed in an attempt
to reach the concept of single session therapy. When we talk about pharmacomechanical thrombectomy or thrombo-aspiration, it really is just one line item on the menu of all the different things that we can offer patients that present with acutely symptomatic PE, but it is important to recognize
what the potential benefits of this technology are and, of course, what the limitations are. When we look at this in distinction to stroke or STEMI or certainly DVT, it's important to recognize that during a surgical pulmonary embolectomy case, the clot that's able to be extracted is quite impressive,
and this is a very very very sobering amount of material that is typically removed from the patient's right heart and their pulmonary circulation, so, in order to innovate and iterate a percutaneous technology based on existing concepts,
it really does demand significant disruption to achieve the goals, we have not tackled this yet in terms of our endovascular tool kit. So, what is the role? Well, it's potentially able to debulk in acute PE, in an intermediate risk patient which would
ideally eliminate the need for overnight lysis, as Gary alluded to, but what if it could actually replace surgical embolectomy in high risk patients? I think many of us have had the conversation where we, we sort of don't know that's there a
experienced, comfortable surgeon to do an embolectomy within the building or within immediate access to the patient that we see crashing in front of our eyes. I'm very very lucky here in New York that I've incredible cardiovascular surgeons that are able to perform this procedure very very safely 24/7,
but I know that's not the case across the country. So, one of our surgeons who actually came from the Brigham and Women's Hospital in Boston developed this concept, which was the sort of first bridge between surgical embolectomy and percutaneous therapy, which is a large bore aspiration catheter,
it's a 22 French cannula that was originally designed to be placed through a cutdown but can now be placed percutaneously, and I think many of us in the room are familiar with this technology, but essentially you advance this under fluoroscopy into the right heart,
place the patient on venous-venous bypass, and a trap, which is outside the patient, is demonstrated in the lower left portion of the screen here, is able to capture any thrombotic material and then restore the circulation via the contralateral femoral vein,
any blood that is aspirated. Very very scant data on this, here's the experience from Michael and Kenny up in Boston where they tried this technology in just a handful of cases, this was followed by John Moriarty's experience from UCLA, where he actually argued a little bit of caution
using this technology, largely related to its inability to safely and reliably deliver it to the pulmonary circulation. To that end, AngieDynamics is funding a prospective registry really looking at safety and efficacy at delivering this device to the pulmonary circulation
and its ability to treat acute pulmonary embolism as well as any right heart clot, but that data's not commercially available yet. This is just one case that we did recently of a clot in transit, which I would argue could not be treated with any other technology
and the patient was able to be discharged the same day, I personally think this is a wonderful application of this technology and is our default strategy right now for a very large clot in transit. The second entrance to the space is the Inari FlowTriever device, which is a 20 French cannula,
it does not require a perfusion team in vein-vein bypass, the concept is simple, a 20 French guide catheter is advanced into the pulmonary circulation and these trilobed disks, which function like a stentriever for stroke are deployed in the pulmonary circulation, retracted to allow the clot to be delivered to the guide cath,
and then using manual aspiration, the clot is retrieved from the patient. Just a few case reports in small series describing this, this one in JACC two years ago, showing quite robust ability to extract a clot, this company which is a relatively small company funded a
single-arm prospective trial enrolling 168 patients, and not only did they complete enrollment last year, but they actually received FDA approval, now there is no peer-reviewed literature on this, it has undergone public presentation, but we, we really don't know exactly which patients were treated,
and so we really can't dissect this, I think there is a learning curve to this technology, and it's not, certainly, ready for broad dissemination yet, we just don't know which patients are ideal for it currently. Another technology, the Penumbra CAT8 system,
a market reduction in the size, an 8 French catheter based technology, this is exact same technology that's used for thrombo-aspiration for acute ischemic stroke, currently just in a slightly different size, and then a number of cases demonstrating its efficacy at
alleviating the acute nonperfusion of an entire lobe, as Gary was referring to previously, and this is one of our cases from our own lab, where you see there's no perfusion of the right, middle and lower lobe, I'm not sure if I can get these movies to play here, oh here it goes,
and so using sort of a handmade separator, we were able to restore perfusion again to the right, middle and lower lobe here, so just one example where, I think there is a potential benefit of thrombo-aspiration in a completely occluded segment.
There has been a wealth of literature about this technology, mostly demonstrating safety and efficacy, the most recent one on the bottom right in CVIR demonstrates the ability to acutely reduce the PA pressures on the table with the use of this technology, and to that end,
Akhi Sista, our faculty here this morning, is the national principal investigator of a US multicenter prospective study looking at exactly that, to try and prove that this technology is safe and effective in the treatment of submassive pulmonary embolism, so more to come on that.
Lastly, the AngioJet System, probably the most reported and studied technology, this is a 6 French technology by default, a wealth of literature here showing safety and efficacy, however, due to adverse event reporting, this technology currently has black box label warnings
in the treatment of acute pulmonary embolism, so clearly this technology should not be used by the novice, and there are significant safety concerns largely related to bradyarrhythmias and hypotension, that being said, again, it is a quite experienced technology for this. So where do we currently stand?
I think we clearly see there are several attributes for thrombo-aspiration including just suction aspiration, a mechanical stent-triever technology, and the ability to not just insanguinate the patient but actually restore circulation and not make the patient anemic, here,
you can see where these technologies are going in terms of very very large bore and very small bore, I placed the question marked right in the center which is where I think this technology needs to converge in order to lead to the disruption for the broad adoption of a single session technology.
So, numerous devices exist, all the devices have been used clinically and have demonstrated the ability to be delivered in aspirary pulmonary embolus, at present, unfortunately there is no consensus regarding which device should be used for which patients and in which clinical presentations,
we need many prospective studies to demonstrate the safety and clinical benefit for our patients, we desperately do need a single session therapy, again, I completely agree with Gary on this, but there is a lot of work yet to do. Thank you for your attention.
- 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.
- Great, thank-you very much, a pleasure to be here. My disclosures. So, we've talked a little bit about obviously percutaneous and thrombectomy techniques. Obviously we have catheter-directed thrombolysis with TPA, but what happens when we can't use TPA
mechanical techniques? We've discussed several of them already in this session, I'm going to try to kind of bring them together and note the differences and how they evolved. And really look at fragmentation, rheolytic therapy, vacuum assisted devices, and vacuum and suction devices.
So when do we need these? Patients that can't tolerate thrombolysis, can't get TPA, that have a high risk of TPA, or maybe there is a situation we need a rapid response. We're trying to create flow and establish flow as much as possible and a lot of times we use this
in combination therapy if we've already hurt. What's the ideal device? I think there are multiple different characteristic's that could define the ideal device. Obviously we want it simple to use, We want it to be reproducible,
we want it to remove a lot of thrombus, but minimize blood loss and trauma to the vessels and to the blood cell. These are just some of them. There's a lot of mechanical thrombectomy devices right now on the market continuing to grow,
both in the arterial and venous system so I think this is going to be an evolution. We started really using mechanical fragmentation with a pig tail and spinning a pig tail. We used that. A lot of times the patient with severe massive pulmonary embolism.
These we're really small antidotes, small case reports. Will Kuo, looked at these in the 2009 and basically saw over all clinical success, about 86% using these mechanical devices. Then we had some that were even more automated.
All these did was break up the clot. So you have the Trerotola Device , Cleaner Device, really almost in the dialysis space. Rheolytic Throbectomy, we've already heard about. Some of how it works and the advantages. Really I think this is the first time we've saw
a system which would try to aspirate and remove some of that thrombus as it got broken up. The PEARL registry really showed for the first time, maybe we can get this done within 24 hours, can we get this done in one session? Unfortunately in this registry only about three or
four percent of patients actually had just rheolytic therapy alone without any TPA. We've discussed a little bit about the use of Ango and this type of device in terms of bradyarrhythmia's and that may be a limitation. But I think we can still use it particularly
outside of the chest. So What about suction devices? You can have a catheter, I think a catheter suction device is very limited. We use that in the arterial tree when there is a small thrombus, a small embolus, I think
we're very limited, not only in the amount of thrombus we can remove but the amount of suction we can apply. Other types like almost mechanical, very simple to use systems is the aspire device. Well you can basically create and suction a
limited area and then help you aspirate the thrombus. And then to the other extreme. We're going to hear my next speaker talk about Angiovac, again a different system, a different system requires a patient on bypass large 26 french devices.
Where we can actually go in and deal with a large amount of thrombus, like this patient had a thrombus cave on both iliac veins. And to be able to basically come with this vacuum aspiration system over wires and kind of pulling them out and you get these little canisters,
seeing what you've actually removed. Very gratifying. But takes a lot of work to get it going. We've heard a little bit about vacuum assisted with the Indigo system. With a system of creating a constant continuous vacuum.
We now have eight french catheters with incredible aspiration volume, almost 20cc's, I'm sorry you can get up to 140cc's of thrombus in a minute can be aspirated quickly. Here is a patient, 80 years old, colorectal CA. You can see the thrombus in the right leg.
There was actually a mass invading this vein. That is where we wanted to use thrombolysis, really went a head and you can see the amount of thrombus. Cleared this out with some passage. You can see this here, the separator. You started seeing thrombus especially when
its acute it kind of looks like this. It's kind of gelatinous, things that we've already seen, and then went ahead and placed a stent, dilated that stent. Had to clean up some more with the device
on top of the stent, but with a good result without needing any TPA. Other types of extraction devices we've seen the Inari device, again this is like a stent Triever device, a nitinol ring we can use this in the pulmonary arteries.
And we've already seen previous and talked about the ClotTriever device Again remove that thrombus, put it into a bag and remove it. So again, capture and removal of thrombus. And this is a solution without the need of TPA. New kid in the block the JETi device
Again very similar to aspiration Indego device, but at the same time it has a jet to macerate the clot and kind of break up the clot a little to smaller areas so we can able to thromb and take more out. I think really here what I've seen and Dr. Razavi
showed me this case. Being able to treat a patient quickly, treat that patient very quickly you can see the amount of thrombus being able to, within about an hour and 15 minutes, get all that thrombus, then create patency in that vein and he showed
some early initial good data. Over the last year we did have a paper that was presented here and published this year in the Journal of Vascular Surgery, venous and lymphatic disorders and again pulled multiple patient's, again showing that
it affective and safe. We still need better data. We need to figure out which patients are best treated with which devices and which again will be affective. Thank-you very much.
- Good morning everybody. Here are my disclosures. So, upper extremity access is an important adjunct for some of the complex endovascular work that we do. It's necessary for chimney approaches, it's necessary for fenestrated at times. Intermittently for TEVAR, and for
what I like to call FEVARCh which is when you combine fenestrated repair with a chimney apporach for thoracoabdominals here in the U.S. Where we're more limited with the devices that we have available in our institutions for most of us. This shows you for a TEVAR with a patient
with an aortic occlusion through a right infracrevicular approach, we're able to place a conduit and then a 22-french dryseal sheath in order to place a TEVAR in a patient with a penetrating ulcer that had ruptured, and had an occluded aorta.
In addition, you can use this for complex techniques in the ascending aorta. Here you see a patient who had a prior heart transplant, developed a pseudoaneurysm in his suture line. We come in through a left axillary approach with our stiff wire.
We have a diagnostic catheter through the femoral. We're able to place a couple cuffs in an off-label fashion to treat this with a technically good result. For FEVARCh, as I mentioned, it's a good combination for a fenestrated repair.
Here you have a type IV thoraco fenestrated in place with a chimney in the left renal, we get additional seal zone up above the celiac this way. Here you see the vessels cannulated. And then with a nice type IV repaired in endovascular fashion, using a combination of techniques.
But the questions always arise. Which side? Which vessel? What's the stroke risk? How can we try to be as conscientious as possible to minimize those risks? Excuse me. So, anecdotally the right side has been less safe,
or concerned that it causes more troubles, but we feel like it's easier to work from the right side. Sorry. When you look at the image intensifier as it's coming in from the patient's left, we can all be together on the patient's right. We don't have to work underneath the image intensifier,
and felt like right was a better approach. So, can we minimize stroke risk for either side, but can we minimize stroke risk in general? So, what we typically do is tuck both arms, makes lateral imaging a lot easier to do rather than having an arm out.
Our anesthesiologist, although we try not to help them too much, but it actually makes it easier for them to have both arms available. When we look at which vessel is the best to use to try to do these techniques, we felt that the subclavian artery is a big challenge,
just the way it is above the clavicle, to be able to get multiple devices through there. We usually feel that the brachial artery's too small. Especially if you're going to place more than one sheath. So we like to call, at our institution, the Goldilocks phenomenon for those of you
who know that story, and the axillary artery is just right. And that's the one that we use. When we use only one or two sheaths we just do a direct puncture. Usually through a previously placed pledgeted stitch. It's a fairly easy exposure just through the pec major.
Split that muscle then divide the pec minor, and can get there relatively easily. This is what that looks like. You can see after a sheath's been removed, a pledgeted suture has been tied down and we get good hemostasis this way.
If we're going to use more than two sheaths, we prefer an axillary conduit, and here you see that approach. We use the self-sealing graft. Whenever I have more than two sheaths in, I always label the sheaths because
I can't remember what's in what vessel. So, you can see yes, I made there, I have another one labeled right renal, just so I can remember which sheath is in which vessel. We always navigate the arch first now. So we get all of our sheaths across the arch
before we selective catheterize the visceral vessels. We think this partly helps minimize that risk. Obviously, any arch manipulation is a concern, but if we can get everything done at once and then we can focus on the visceral segment. We feel like that's a better approach and seems
to be better for what we've done in our experience. So here's our results over the past five-ish years or so. Almost 400 aortic interventions total, with 72 of them requiring some sort of upper extremity access for different procedures. One for placement of zone zero device, which I showed you,
sac embolization, and two for imaging. We have these number of patients, and then all these chimney grafts that have been placed in different vessels. Here's the patients with different number of branches. Our access you can see here, with the majority
being done through right axillary approach. The technical success was high, mortality rate was reasonable in this group of patients. With the strokes being listed there. One rupture, which is treated with a covered stent. The strokes, two were ischemic,
one hemorrhagic, and one mixed. When you compare the group to our initial group, more women, longer hospital stay, more of the patients had prior aortic interventions, and the mortality rate was higher. So in conclusion, we think that
this is technically feasible to do. That right side is just as safe as left side, and that potentially the right side is better for type III arches. Thank you very much.
- 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.
- Thank you very much both. It was a great pleasure to see you. I continue to be grateful for the guidance you have given me over the years. Thank you to the organizers for advising me to speak. These are my disclosures. So really there are two questions posed by this topic.
One is, is the patent popliteal vein necessary? I would assume from this is it necessary for patency and symptom relief to be achieved in treating patients with both acute DVT and potentially chronic. And has the evolution formic mechanical therapy
led to over stenting. Which means we have to ask the question what is an appropriate rate for stenting. I am not sure we know the answer to that. So being able to answer over stenting requires us to know how many patients
actually need the stent in the first place in acute DVT treatments. The problem is essentially this. Is that when we form lithic therapies and this is a classic case of treatment formed with formic and mechanical device
but without a follow up using lithic in the patient for whom lithic was not feasible. You end up opening up a vessel but you can see from the image on the left hand side that there is a degree still of luminol contrast deficit suggesting some cult left behind
in the external iliac vein. Well there is obviously a May-Thurner legion at the top. The question of over stenting is one of do we just stent the May-Thruner and extend it down into the external iliac vein to trap that thrombus
or would a period of time of lithic have resulted in this clot resolving and not needed a stent at the end of it. To get to the question of how many people should be stented. The only way we can really do this
is try and exstipulate from the literature to some extent. This is the short and long term outcome from the Kevin study. Where there is ultrasound follow up of patients underwent standard treatment only.
And a additional group in the patients had catheter-directed thrombolysis. We can see there that the patients did six months in catheter-directed thrombolysis group is around 60%. And the patency seen with the non treated group
is around 40%. If we kind of use these numbers as a guide we probably expect therefore that the stent rate would be somewhere between 40 and 60 percent. To account for treating the outflow structure that presumably patients see at six months.
But this is clearly not a very rebost method of being absolutely clear on who needs stents. Additional method is we don't really have and answer for who should be stented at the end of a procedure. So if you look at the massive variability
in the other studies. We see that attract stent rate is approximately 28% for the study. Which is obviously a operative discretion and has been criticized for that reason. But there is no comment on the Popliteal vein
or Popliteal vein patency. Cavent did an stent rate of 15% again with no real comment on whether the Popliteal vein was open and it wasn't a prerequisite for treatment in the study. This contrast with the Ansberg Aspirex Registry.
Which is a registry of a purely mechanical device to aspirex clot and the stent rate is 100%. Baekgaard Copenhagen used a catered-directed thrombolysis with a mandated open popliteal vein for purpose to be in the study. He has a stent rate of 60%.
My own personal experience of 160 odd patients is that were stenting around 80% of patients with outflow legion at the end of treatment. And were not really bothered by whether the popliteal vein is clear or not. But that doesn't necessarily answer the question
whether it makes a difference in the long run. So its very difficult even looking at the data we have because there is no standard definition of what a outflow stenosis is. There is no objective measure for an outflow stenosis. So stenting becomes and operative discretion decision.
But you would have to say that if your taking purely mechanical devices and the stent rates are going up to 100% that the inclination would be that there is potential for formic mechanical therapy to lead to overstenting and increase use
for stents for sure. In our experience then we had 81 patients who had CDT alone verse 70 patients who had AngioJet Thrombectomy. The basic characteristics of the group are pretty much identical.
With similar ages and no difference between whether the thrombus with left side or right side of body or so on. And these are the patency curves for the different groups with equivalent primary, primary assisted and secondary patency over two yeas.
We had no difference in stent rates with the median stenting of 80% in both groups with two stents used in average for each of those patients. However in our practice AngioJet is rarely used alone. So we had 70 patients for whom AngioJet was used. 24 of those where AngioJet was used up front
as the first line of treatment followed by some CDT. We have tended find that if we wanted full clock clearance. We have always had omit to some extent. And single stage therapy is quite difficult to achieve unless you spent a lot of time in it.
Patency in the popliteal vein is clearly affected by some extent. These are our follow up results if we don't have a patent popliteal vein at the end. It does drop off in stent patency. So the conclusions then I think.
Is that patent popliteal vein is necessary for long term results. But you can still treat patients that have acute popliteal vein for larsons that is not a contraindication. Pure mechanical therapies may well lead to higher stent rate.
But is this a bad thing or a good thing? We don't really know this at this stage as to what the long term outcomes will be. Thank you very much.
- Thank you so much. We have no disclosures. So I think everybody would agree that the transposed basilic vein fistula is one of the most important fistulas that we currently operate with. There are many technical considerations
related to the fistula. One is whether to do one or two stage. Your local criteria may define how you do this, but, and some may do it arbitrarily. But some people would suggest that anything less than 4 mm would be a two stage,
and any one greater than 4 mm may be a one stage. The option of harvesting can be open or endovascular. The option of gaining a suitable access site can be transposition or superficialization. And the final arterial anastomosis, if you're not superficializing can either be
a new arterial anastomosis or a venovenous anastomosis. For the purposes of this talk, transposition is the dissection, transection and re tunneling of the basilic vein to the superior aspect of the arm, either as a primary or staged procedure. Superficialization is the dissection and elevation
of the basilic vein to the superior aspect of the upper arm, which may be done primarily, but most commonly is done as a staged procedure. The natural history of basilic veins with regard to nontransposed veins is very successful. And this more recent article would suggest
as you can see from the upper bands in both grafts that either transposed or non-transposed is superior to grafts in current environment. When one looks at two-stage basilic veins, they appear to be more durable and cost-effective than one-stage procedures with significantly higher
patency rates and lower rates of failure along comparable risk stratified groups from an article from the Journal of Vascular Surgery. Meta-ana, there are several meta-analysis and this one shows that between one and two stages there is really no difference in the failure and the patency rates.
The second one would suggest there is no overall difference in maturation rate, or in postoperative complication rates. With the patency rates primary assisted or secondary comparable in the majority of the papers published. And the very last one, again based on the data from the first two, also suggests there is evidence
that two stage basilic vein fistulas have higher maturation rates compared to the single stage. But I think that's probably true if one really realizes that the first stage may eliminate a lot of the poor biology that may have interfered with the one stage. But what we're really talking about is superficialization
versus transposition, which is the most favorite method. Or is there a favorite method? The early data has always suggested that transposition was superior, both in primary and in secondary patency, compared to superficialization. However, the data is contrary, as one can see,
in this paper, which showed the reverse, which is that superficialization is much superior to transposition, and in the primary patency range quite significantly. This paper reverses that theme again. So for each year that you go to the Journal of Vascular Surgery,
one gets a different data set that comes out. The final paper that was published recently at the Eastern Vascular suggested strongly that the second stage does consume more resources, when one does transposition versus superficialization. But more interestingly also found that these patients
who had the transposition had a greater high-grade re-stenosis problem at the venovenous or the veno-arterial anastomosis. Another point that they did make was that superficialization appeared to lead to faster maturation, compared to the transposition and thus they favored
superficialization over transposition. If one was to do a very rough meta-analysis and take the range of primary patencies and accumulative patencies from those papers that compare the two techniques that I've just described. Superficialization at about 12 months
for its primary patency will run about 57% range, 50-60 and transposition 53%, with a range of 49-80. So in the range of transposition area, there is a lot of people that may not be a well matched population, which may make meta-analysis in this area somewhat questionable.
But, if you get good results, you get good results. The cumulative patency, however, comes out to be closer in both groups at 78% for superficialization and 80% for transposition. So basilic vein transposition is a successful configuration. One or two stage procedures appear
to carry equally successful outcomes when appropriate selection criteria are used and the one the surgeon is most favored to use and is comfortable with. Primary patency of superficialization despite some papers, if one looks across the entire literature is equivalent to transposition.
Cumulative patency of superficialization is equivalent to transposition. And there is, appears to be no apparent difference in complications, maturation, or access duration. Thank you so much.
- So this is what I've been assigned to do, I think this is a rich topic so I'll just get into it. Here are my disclosures. So I hope to convince you at the end of this talk that what we need for massive PE when we're talking about catheter based therapy is a prospective registry. And what we need for catheter based therapy for
submassive PE is a randomized controlled trial. So we'll start with massive PE and my rational for this. So you know, really as you've heard, the goal of massive PE treatment is to rescue these patients from death. They have a 25 to 65% chance of dying
so our role, whatever type of physician we are, is to rescue that patient. So what are our tools to rescue that patient? You've heard about some of them already, intravenous thrombolysis, surgical embolectomy, and catheter directed therapy.
The focus of my talk will be catheter directed therapy but let's remember that the fastest and easiest thing to do for these patients is to give them intravenous thrombolysis. And I think we under utilize this therapy and we need to think about this as a first line therapy for massive PE.
However, there's some patients in whom thrombolytics are contraindicated or in whom they fail and then we have to look at some other options. And that's where catheter directed therapy may play a role. So I want to show you a pretty dramatic case and this was an eye-opening case for me
and sort of what launched our PERT when I was at Cornell. It's a 30 year old man, transcranial resection of a pituitary tumor post-op seizures and of course he had a frontal lobe hemorrhage at that time. Sure enough, four or five days after this discovery
he developed hypertension and hypoxia. And then is he CT of the chest, which I still remember to this day because it was so dramatic. You see this caval thrombosis right, basically a clot in transit
and this enormous clot in the right main pulmonary artery. And of course he was starting to get altered, tachycardiac and a little bit hypotensive. So the question is, what to do with this patient with an intracranial hemorrhage? Obviously, systemic thrombolytics are
contraindicated in him. His systolics were in the 90 millimeter of mercury ranged, getting more altered and tachycardiac. He was referred for a CDT and he was brought to the IR suite. And really, at this point,
you could see the multidisciplinary nature of PE. The ICU attending was actively managing him while I was getting access and trying to do my work. So this was the initial pulmonary angiogram you can see there's absolutely no flow to the right lung even with a directed injection
you see this cast of thrombus there. Tried a little bit of aspiration, did a little bit of maceration, even injected a little TPA, wasn't getting anywhere. I was getting a little bit more panicked as he was getting more panicked
and I remembered this device that I had used in AV fistula work called the Cleaner. Totally off label use here, I should disclose that and I have no interest in the company, no financial interest in the company. And so we deployed this thing, activate it a few times,
it spins at 3,000 rpm's, he coughed a little bit, and that freaked us all out also. But low and behold we actually started seeing some profusion. And you can see it in the aortogram actually in this and that's the whole point of massive PE treatment with CDT,
is try to get forward flow into the left ventricle so that you have a systemic blood pressure. Now, you know, when we talk about catheter based therapies we have all sorts of things at our disposal. And my point to you is that you know really, thank you...
You guys can see that, great. So really, the point of these catheter therapies is that you can throw the kitchen sink at massive PE because basically your role is to try to help this patient live. So, if I can get this thing to show up again.
There we go. It's not working very well, sorry. So, from clockwise we have the AngioVac circuit, you have, let's see if this will work again, okay. Nope, it's got a delay. So then you have your infusion catheter,
then you have the Inari FlowTriever, you saw the Cleaner in the previous cast, and you have the Penumbra aspiration device the CAT 8. And some of these will be spoken about in more detail in subsequent talks. But really, you can throw the kitchen sink at massive PE
just to do whatever it takes to get profusion to the left side. So, the best analysis that has been done so far was Will Kuo in 2009. He conducted a meta-analysis of about 594 patients and he found this clinical success rate of 86.5%.
This basically meant these patients survived to 30 days. Well, if that we're the case, that's a much lower mortality than we've seen historically we should basically be doing catheter directed therapy for every single massive PE that comes into the hospital. But I think we have to remember with this meta-analysis
that only 94 of these patients came from prospective studies, 500 came from retrospective, single center studies. So even though it was a very well conducted meta-analysis, the substrate for this meta-analysis wasn't great. And I think my point to you is that
we really are going to have a hard time studying this in a prospective fashion. So what is the data, as far as massive PE tell us and not tell us? Techniques are available to remove thrombus, it can be used if systemic lysis is contraindicated,
but it doesn't tell us whether catheter based therapies are better than the other therapies. Whether they should be used in combination with them and which patients should get catheter based therapy, which should get surgery and which techniques are most effective and safe.
Now, I think something we have to remember is that massive PE has a 5% incidence which is probably a good thing, if this was even higher than that we would have even more of an epidemic on our hand. But this is what makes massive PE very difficult to study.
So, if you looked at a back of the envelope calculation an RCT is just not feasible. So in an 800 bed hospital, you have 200 PE's per year, 5% are massive which means you get 10 per year in that hospital, assume 40% enroll which is actually generous,
that means that 4 massive PE's per year per institution. And then what are you going to do? Are you going to randomize them to IV lytics versus surgery versus interventional therapy, a three arm study, what is the effect size, what difference do you expect between these therapies
and how would you power it? It's really an impossible question. So I do want to make the plug for a Massive PE Prospective Registry. I think something like the PERT consortium is very well-suited to run something like this
especially with this registry endeavors. Detailed baseline characteristics including all these patients, detailing the intervention and looking at both short and long-term outcomes. Moving on to submassive PE. As you've heard much more controversial,
a much more difficult question. ICOPER as you already heard from the previous talk, alerted the world to RV dysfunction which this right ventricular hypokinesis conferring a higher mortality at 90 days than no RV dysfunction. And that's where PEITHO came in as you heard.
This showed that the placebo group met the primary endpoint of hemodynamic decompensation more commonly than the Tenecteplase group. Of course, coming at the risk of higher rate of major bleeding and intracranial hemorrhage. So I just want to reiterate what was just said
which is that systemic thrombolysis has a questionable risk benefit profile and most patients with submassive PE, as seen in the guideline documents as well. So that sort of opens a sort of door for catheter directed therapy.
Is this the next therapy to overcome some of the shortcomings of systemic thrombolysis? Well what we have in terms of CDT is these four trials, Ultima, Seattle II, Optalyse, and Perfect. Three of these trails were the ultrasound assisted catheter, the Ekos catheter.
And only one of them is randomized and that's the Ultima trial. I'm going to show you just one slide from each one of them. The Ultima trial is basically the only randomized trial and it showed that if you put catheters in these patients 24 hours later their RV to LV ratio will be lower
than if you just treat them with Heparin. Seattle II is a single arm study and there was an association with the reduction in the RV to LV ratio at 48 hours by CTA. PERFECT, I found this to be the most interesting figure from PERFECT which is that you're going to start it at
systolic pulmonary artery pressure of 51 and you're going to come down to about 37. Optalyse, a brand new study that was just published, four arms each arm has increasing dose associated with it and at 48 hours it didn't matter, all of these groups had a reduction in the RV to LV ratio.
And there was no control group here as well. What is interesting is that the more thrombolytics you used the more thrombus you cleared at 48 hours. What that means clinically is uncertain at this point. There is bleeding with CDT. 11% major bleeding rate in Seattle II,
no intracranial hemorrhages. Optalyse did have five major bleeds, most of the major bleeds happened in the highest dosed arms. So we know that thrombolytics cause bleeding that's still an issue. Now, clot extraction minus fibrinolytic,
this is an interesting question. We do have devices, you're going to hear about the FLARE trial later in this session. EXTRACT-PE is ongoing which we have enrolled about 75 patients into. What the data does and does not tell us
when it comes to CDT for submassive PE it probably reduces the RV to LV ratio at 24 hours, it's associated with a reduction at 48 hours, major bleeding is seen, we do not know what the short and long-term clinical outcomes are
following CDT for submassive PE. Whether it should be routinely used in submassive PE and in spite of the results of Optalyse this is a preliminary trial, we don't know the optimal dose and duration of thrombolytic drug. And even is spite of these early trials
on these non-lytic techniques, we don't know their true role yet. I'd liked to point out that greater than 1,600 patients have been randomized in systemic lytic trails yet only 59 have been randomized in a single, non-U.S. CDT trial.
So this means that you can randomize patients with submassive PE to one treatment or the other. And we want to get away from this PERT CDT roller coaster where you get enthusiasm, you do more cases, then you have a complication, then the number of cases drops.
You want that to be consistent because you're basing it on data. And that's where we're trying to come up with a way of answering that with this PE-TRACT trial. Which is a RCT of CDT versus no-CDT. We're looking at clinical endpoints
rather than radiographic ones greater than 400 patients, 30 to 50 sites across the country. So in summary I hope I've convinced you that we need a Prospective Registry for massive PE and a Randomized Controlled Trail for submassive PE. Thank you.
- Good morning. I'd like to thank everybody who's in attendance for the 7 A.M. session. So let's talk about a case. 63 year old male, standard risk factors for aneurismal disease. November 2008, he had a 52 mm aneurism,
underwent Gore Excluder, endovascular pair. Follow up over the next five, relatively unremarkable. Sac regression 47 mm no leak. June 2017, he was lost for follow up, but came back to see us. Duplex imaging CTA was done to show the sac had increased
from 47 to 62 in a type 2 endoleak was present. In August of that year, he underwent right common iliac cuff placement for what appeared to be a type 1b endoleak. September, CT scan showed the sac was stable at 66 and no leak was present. In March, six months after that, scan once again
showed the sac was there but a little bit larger, and a type two endoleak was once again present. He underwent intervention. This side access on the left embolization of the internal iliac, and a left iliac limb extension. Shortly thereafter,
contacted his PCP at three weeks of weakness, fatigue, some lethargy. September, he had some gluteal inguinal pain, chills, weakness, and fatigue. And then October, came back to see us. Similar symptoms, white count of 12, and a CT scan
was done and here where you can appreciate is, clearly there's air within the sac and a large anterior cell with fluid collections, blood cultures are negative at that time. He shortly thereafter went a 2 stage procedure, Extra-anatomic bypass, explant of the EVAR,
there purulent fluid within the sac, not surprising. Gram positive rods, and the culture came out Cutibacterium Acnes. So what is it we know about this case? Well, EVAR clearly is preferred treatment for aneurism repair, indications for use h
however, mid-term reports still show a significant need for secondary interventions for leaks, migrations, and rupture. Giles looked at a Medicare beneficiaries and clearly noted, or at least evaluated the effect of re-interventions
and readmissions after EVAR and open and noted that survival was negatively impacted by readmissions and re-interventions, and I think this was one of those situations that we're dealing with today. EVAR infections and secondary interventions.
Fortunately infections relatively infrequent. Isolated case reports have been pooled into multi-institutional cohorts. We know about a third of these infections are related to aortoenteric fistula, Bacteremia and direct seeding are more often not the underlying source.
And what we can roughly appreciate is that at somewhere between 14 and 38% of these may be related to secondary catheter based interventions. There's some data out there, Matt Smeed's published 2016, 180 EVARs, multi-center study, the timing of the infection presumably or symptomatic onset
was 22 months and 14% or greater had secondary endointerventions with a relatively high mortality. Similarly, the study coming out of Italy, 26 cases, meantime of diagnosis of the infection is 20 months, and that 34.6% of these cases underwent secondary endovascular intervention.
Once again, a relatively high mortality at 38.4%. Study out of France, 11 institutions, 33 infective endographs, time of onset of symptoms 414 days, 30% of these individuals had undergone secondary interventions. In our own clinical experience of Pittsburgh,
we looked at our explants. There were 13 down for infection, and of those nine had multiple secondary interventions which was 69%, a little bit of an outlier compared to the other studies. Once again, a relatively high mortality at one year. There's now a plethora of information in the literature
stating that secondary interventions may be a source for Bacteremia in seeding of your endovascular graft. And I think beyond just a secondary interventions, we know there's a wide range of risk factors. Perioperative contamination, break down in your sterile technique,
working in the radiology suite as opposed to the operating room. Wound complications to the access site. Hematogenous seeding, whether it's from UTIs, catheter related, or secondary interventions are possible.
Graft erosion, and then impaired immunity as well. So what I can tell you today, I think there is an association without question from secondary interventions and aortic endograft infection. Certainly the case I presented appears to show causation but there's not enough evidence to fully correlate the two.
So in summary, endograft infections are rare fortunately. However, the incidence does appear to be subtly rising. Secondary interventions following EVAR appear to be a risk factor for graft infection. Graft infections are associated without question
a high morbidity and mortality. I think it's of the utmost importance to maintain sterile technique, administer prophylactic antibiotics for all secondary endovascular catheter based interventions. Thank you.
- I'd like to thank Dr. Veith and the committee for the privilege of presenting this. I have no disclosures. Vascular problems and the type of injuries could be varied. We all need to have an awareness of acute and chronic injuries,
whether they're traumatic, resulting with compression, occlusion, tumoral and malformation results, or vasospastic. I'd like to present a thoracoscopic manipulation of fractured ribs to prevent descending aortic injury
in a patient with chest trauma. You know, we don't think about this but they can have acute or delayed onset of symptoms and the patient can change and suddenly deteriorate with position changes or with mechanical ventilation,
and this is a rather interesting paper. Here you can see the posterior rib fracture sitting directly adjacent to the aorta like a knife. You can imagine the catastrophic consequences if that wasn't recognized and treated appropriately.
We heard this morning in the venous session that the veins change positions based on the arteries. Well, we need to remember that the arteries and the whole vascular bundle changes position based on the spine
and the bony pieces around them. This is especially too when you're dealing with scoliosis and scoliotic operations and the body positioning whether it's supine or prone the degree of hypo or hyperkyphosis
and the vertebral angles and the methods of instrumentation all need to be considered and remembered as the aorta will migrate based on the body habits of the patient. Screws can cause all kinds of trouble.
Screws are considered risky if they're within one to three millimeters of the aorta or adjacent tissues, and if you just do a random review up to 15% of screws that are placed fall into this category.
Vertebral loops and tortuosity is either a congenital or acquired anomaly and the V2 segment of the vertebral is particularly at risk, most commonly in women in their fifth and sixth decades,
and here you can see instrumentation of the upper cervical spine, anterior corpectomy and the posterior exposures are all associated with a significant and lethal, at times, vertebral artery injuries.
Left subclavian artery injury from excessively long thoracic pedicle screws placed for proximal thoracic scoliosis have been reported. Clavicular osteosynthesis with high neurovascular injury especially when the plunge depth isn't kept in mind
in the medial clavicle have been reported and an awareness and an ability to anticipate injury by looking at the safe zone and finding this on the femur
with your preoperative imaging is a way to help prevent those kinds of problems. Injuries can be from stretch or retraction. Leave it to the French. There's a paper from 2011 that describes midline anterior approach
from the right side to the lumbar spine, interbody fusion and total disc replacement as safer. The cava is more resistant to injury than the left iliac vein and there's less erectile dysfunction reported. We had a patient present recently
with the blue bumps across her abdomen many years after hip complicated course. She'd had what was thought to be an infected hip that was replaced, worsening lower extremity edema, asymmetry of her femoral vein on duplex
and her heterogeneous mask that you can see here on imaging. The iliac veins were occluded and compressed and you could see in the bottom right the varicosities that she was concerned about. Another case is a 71-year-old male who had a post-thrombotic syndrome.
It was worsened after his left hip replacement and his wife said he's just not been the same since. Initially imaging suggests that this was a mass and a tumor. He underwent biopsy
and it showed ghost cells. Here you can see the venogram where we tried to recanalize this and we were unsuccessful because this was actually a combination of bone cement and inflammatory reaction.
Second patient in this category, bless you, is a 67-year-old female who had left leg swelling again after a total hip replacement 20 plus years ago. No DVTs but here you can see the cement compressing the iliac vein.
She had about a 40% patency when you put her through positioning and elected not to have anything done with that. Here you could see on MR how truly compressed this is. IVA suggested it was a little less tight than that.
So a vascular injury occurs across all surgical specialties. All procedures carry risk of bleeding and inadvertent damage to vessels. The mechanisms include tearing, stretching, fracture of calcific plaques,
direct penetration and thermal injury. The types of injuries you hear are most common after hip injuries, they need to be recognized in the acute phase as looking for signs of bleeding or ischemia. Arterial lesions are commonly prone then.
Bone cement can cause thermal injury, erosion, compression and post-implant syndrome. So again, no surgery is immune. You need to be aware and especially when you look at patients in the delayed time period
to consider something called particle disease. This has actually been described in the orthopedic literature starting in the 70s and it's a complex interaction of inflammatory pathways directed at microparticles that come about
through prosthetic wear. So not only acute injury but acute and chronic symptoms. Thank you for the privilege of the floor.
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