External iliac remote endarterectomy restores the artery to normal, opening the way for EVAR, TAVR, TEVAR, and transplant: alternate applications of EndoRE

preop-cta

One of the nice things  about practicing at the Clinic is being able to offer unique solutions. A severely diseased or occluded external iliac artery (EIA) can be a vexing problem, particularly if bilateral, in this endovascular era. Many cardiovascular devices require femoral access that has to traverse compromised iliac arteries -those with large (>16F) delivery systems require a sufficiently wide path to get the devices to the heart and aorta. Also, living related donor kidney transplantation is predicated on minimizing risk to maximize results and having significant iliac plaque negates one as a recipient for this high stakes elective procedure. In situations where the EIA is too small to accommodate devices because of atherosclerotic plaque, the typical solution is placement of a conduit to the common iliac artery or the aorta. The practice of “endopaving” with a covered stent graft and ballooning is also described, but its long term outcomes are not reported and the internal iliac artery is usually sacrificed in this maneuver.

This patient presents with lifestyle limiting claudication and an absent right femoral pulse. ABI is moderately reduced on the right to 0.57, and he had no rest pain. CTA at our clinic revealed an occluded EIA bracketed by severely calcified and nearly occlusive plaque of the common iliac artery (CIA) and common femoral artery (CFA).

cta-preop_7
Centerline Projection

The patient was amenable to operation. Traditionally, this would have been treated with some form of bypass -aortofemoral or femorofemoral with a common femoral endarterectomy. While endovascular therapy of the occluded segment is available, one should not expect the patencies to be any better than that of occlusive lesions (CTO’s) in other arteries. Hybrid open/endovascular therapy is an option as well with CFA endarterecotmy and crossing CIA to EIA stents, but I have a better solution.

The common femoral endarterectomy rarely ends at the inguinal ligament, and is uniquely suitable for remote endarterectomy, a procedure from the early to mid twentieth century.

endoRE graphic
Steps in Remote Endarterectomy

 

The addition of modern fluoroscopic imaging and combining with endovascular techniques makes this a safe and durable operation.

pre intervention.png

The patient was operated on in a hybrid endovascular OR suite. A right groin incision was made to expose the common femoral artery for endarterectomy and left common femoral access was achieved for angiographic access, but also to place a wire across the occlusion into the common femoral artery.

All actions on the external iliac artery plaque are done with an up-and-over wire, allowing for swift action in the instance that arterial perforation or rupture occur. This event is exceedingly rare when the operation is well planned. With this kind of access, an occlusive balloon or repairing stent graft can be rapidly delivered.

The common femoral endarterectomy is done from its distal most point and the Vollmer ring is used to mobilize the plaque. A Moll Ring Cutter (LeMaitre Vascular) is then used to cut the plaque.

Ring dissection.png

Cutter.png

The plaque is extracted and re-establishes patency of the EIA.

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Plaque Specimen

The plaque end point is typically treated with a stent -in this  case, the common iliac plaque was also treated.

result.png

What is nice about this approach is that this artery has been restored to nearly its original condition. I have taken biopsies of the artery several months after the procedure in the process of using the artery as inflow for a cross femoral bypass, and the artery clamped and sewed like a normal artery and the pathology returned normal artery.

This has several advantages over conduit creation which can be a morbid and high risk procedure in patients who require minimally invasive approach. A graft is avoided. The artery is over 8mm in diameter where with stenting up to 8mm with an occlusive plaque, the danger of rupture is present, and often ballooning is restricted to 6mm-7mm. This is insufficient for many TEVAR grafts and TAVR valves.

For patients being worked up for living related donor transplants who are turned down because of the presence of aortoiliac plaque, those with the right anatomy can undergo this procedure and potentially become candidates after a period of healing.

 

The femoral bifurcation does not tolerate endovascular miscalculation

Sketch185115048

The patient presented with complaints of leg and foot pain with sitting and short distance calf claudication, being unable to walk more than 100 feet. This is unusual because sitting usually relieves ischemic rest pain. He is in late middle age and developed claudication a year prior to presentation that was treated with stent grafting of his superficial femoral artery from its origin to Hunter’s canal at his local hospital. This relieved his claudication only briefly, but when the pain recurred a few months after treatment, it was far worse than what he had originally. Now, when he sat at his desk, his foot would go numb very quickly and he would have to lie down to relieve his pain.

On examination, the patient was moderately obese with overhanging belly. He had a palpable right femoral pulse, but nothing below was palpable. He had multiphasic signals in the dorsalis pedis and posterior tibial arteries. The left leg had a normal arterial exam. Pulse volume recording and segmental pressures were measured:

preop PVR2

These are taken with the patient lying down which was the position that relieved his pain, and the PVR’s show some diminishment of inflow. It would be easy at this point to declare the patient’s pain to be due to neuropathy or spinal stenosis, but because of his inability to walk more than a hundred feet and because of his severe pain with sitting, I went ahead and obtained a CTA.

3DVR

The CTA showed he had an occluded superficial femoral artery (SFA) with patent profunda femoral artery (PFA) with reconstitution of an above knee popliteal artery with multivessel runoff. The 3DVR image showed his inguinal crease to be right over the femoral bifurcation which is not an unsual finding, but his stent graft was partially occluding his profunda femoral artery.

CTA centerline

I decided to take him to the operating room to relieve his PFA of this obstruction. My plan was to remove the stent graft at the origin of the SFA and at the same time, remove the plaque and occluded stent graft from his SFA to restore it to patency.

In the OR, on exposing his SFA, I discovered that because of his overhanging belly, his inguinal ligament had sagged and was compressing his femoral bifurcation.

Sketch185115048

This explained his presentation. The stent graft really had no chance as when he sat, the belly and ligament compressed it at the origin, and because it partially occluded the origin of the PFA, sitting probably pinched off flow completely. The 3dVR image shows the mid segment of PFA to have little contrast density -this is not because of thrombus, but because of the obstruction, the PFA was getting collateral flow from the hypogastric artery.

The stent graft was removed at its origin via a longitudinal arteriotomy after remote endarterectomy of the distal graft.

IMG_7228

In this case, the Multitool (LeMaitre) was useful in dissecting the plaque and stent graft because of its relatively stiff shaft compared to the standard Vollmer rings. The technique of EndoRE has been described in prior posts (link).

procedure picture

The stent graft came out in a single segment -they come out easier than bare stents.

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IMG_7232

post angio compositeThe patient regained palpable pulses in his right foot and recovered well, being discharged home after a 4 day stay.

While one could argue that just taking out the short piece of occlusive stent graft over the PFA was all that was necessary, I feel that there is no added harm in sending down a dissector around the stent, and in this patient there was restoration of his SFA patency which was the intent of the original procedure.

Unlike PTFE bypasses that sometimes fail with thromboembolism, SFA EndoRE fails with development of focal stenoses. From a conversation I had with Dr. Frans Moll at the VEITH meeting, I found that he has had good experience with using drug coated balloons in the treatment of these recurrent stenoses.

At the time of discharge, the patient was relieved of his rest pain, and was no longer claudicating. The common femoral artery, its bifurcation, and the profunda femoral artery remain resistent to attempts at endovascular treatment, and remain in the domain of open surgery. And in retrospect, the history and physical examination had all the clues to the eventual answer to the oddities of the patient’s complaints. The combination of inguinal crease, abdominal pannus, and low hanging inguinal ligament meant these structures acted to crush the stent graft and femoral bifurcation.

The Ilio-femoral-popliteal remote endarterectomy -The Concept Behind Extended Remote Endarterectomy is Moving Inflow from the Groin to the Knee

IMG_6805

Why perform such an extensive endarterectomy when just a few stents will do? This is a valid question, given the relative safety of interventions and the durability of bypasses. There are three reasons why ilio-femoral-popliteal endarterectomy works well in my practice.

  1. Minimally invasive
  2. Restore elasticity and collaterals
  3. Move the inflow point from the groin to the knee

The procedure is minimally invasive. Take for example this patient whose plaque is shown above. He had a common femoral occlusion for which a common femoral endarterectomy was aborted when the prior surgeon ran into excessive bleeding. Workup for coagulopathy was negative and the patient came to me with rest pain. Pedal level pulses were not palpable, and the signals were barely there.

pvr2

CTA showed that he had a CFA occlusion as well as SFA occlusion.

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Because the common femoral plaque is contiguous with the external iliac plaque, it is often simpler to complete a remote endarterectomy over wire up to the external iliac origin than to try to get a satisfactory end point at the inguinal ligament -I do not like stenting across the ligament into the patch which is the usual bailout if the end point causes a stenosis. It is far simpler to apply a stent at the external iliac origin.

The popliteal end point was chosen where the visible plaque was no longer apparent in the patent artery. The goal is to cut across thin intima, and frequently no distal stent is required because a secure end point is achieved much like the “feathered endpoint” seen in carotid endarterectomies.

Termini

distal end point

My intention was to endarterectomize the atherosclerotic plaque from the external iliac origin to popliteal artery via the groin incision marked in orange.

3DVR allows for planning the operation in great detail
3DVR allows for planning the operation in great detail

The video shows the setup and motion in dissecting the plaque.

The plaque came out easily (first image, top).The proximal and distal end points required stents.

Before and after
Before and after

The patient regained palpable dorsalis pedis and posterior tibial artery pulses. Total OR time was less than 2 hours. An ilioinguinal field block allowed for good pain control and the patient was discharged the next morning, having to heal only a 10cm wound. There is no good endovascular option for common femoral disease, and while stenting the whole SFA can be done, on more than a few occasions I have had to treat occluded “full metal jacket” SFA stents, usually by removing them. EndoRE has been shown to be superior to PTFE and almost as good as vein in the REVAS Trial when compared to fem-AK POP bypass. Going home the next day after such an extensive revascularization is not a stunt -it’s the direct result of limiting the incision and blood loss and OR time.

2. Restore Elasticity and Collaterals -Arterial Restoration

One of the components of arterial flow that is lost with atherosclerotic disease is arterial elasticity. That is the stretchiness of the artery in response to pressure. Elastic distension and recoil account for significant portions of forward flow during diastole which is lost with atherosclerotic plaque. As plaque builds up, and the artery becomes stiffer. The artery that goes through remote endarterectomy regains this elasticity. Ultrastructure from a recanalized external iliac artery sampled from a punch arteriotomy for a cross ilio-femoral bypass showed that three months after endarterectomy, the external iliac artery was ultrastructurally normal per pathology report.

Also, collaterals that were previously occluded are seen to be restored to patency. This has an important impact on patency and any future failures. The endarterectomized arteries fail due to the presence of isolated, random fragments of medial smooth muscle which cause focal TASC A restenoses. These are easily amenable to balloon angioplasty. If the revascularization fails, there is no catastrophic thromboembolism that is typical of PTFE thromboses -rather the collaterals keep segments open and it is straightforward to thrombectomize or lyse the artery and intervene as necessary.

3. Moving the inflow point from groin to the knee.

This is an important concept. One of the principles of inflow restoration is delivering large flow and pressure directly from the aortic source to the leg. Recanalizing from the external iliac to the below knee popliteal artery creates this situation below the knee, allowing for very short bypasses to be performed from the popltieal artery to tibial targets -a very useful circumstance when vein is limited. This next patient is a presented with gangrene of his fifth toe after esophagectomy for cancer, and had severe diabetes.

prepvr2

He had useful saphenous vein in his thigh only, some of it having been harvested in the proximal thigh for a common femoral endarterectomy. CTA showed a dilated common femoral and profunda femoral artery, severely calcified SFA and popliteal artery which were occluded, and only a patent peroneal artery as runoff.

no annotation -_3

The plan was to harvest the short segment of vein then through the same incisions, below the knee and in the mid thigh, expose the below knee popliteal artery and tibial origins, and the mid SFA. I intended to avoid the groin. The plaque was removed from the tibioperoneal trunk to the SFA origin, and the origin was stented.

IMG_6637

This reestablished a normal inflow at the level of the below knee popliteal artery. I also did an eversion endarterectomy of the anterior tibial artery which resulted in significant back bleeding -a good sign. A short bypass was performed from the below knee popliteal artery to the peroneal artery.

IMG_6639

This resulted in a palpable dorsalis pedis artery pulse and excellent peroneal and posterior tibial artery signal.

completion

The ABI improved and the waveforms predicted healing for his 5th ray amp.

post abi2

This last case illustrates the point that once the conceptual inflow point is moved to the below knee popliteal artery, bypasses can become short, and durable tibial revascularizations become feasible. By avoiding a redo groin, avoiding multisegment arm vein bypass, and keeping the procedure time under 5 hours, the operation remains less invasive.

My First Intentional Stent Removal Case -Arterial Restoration

removed stents

In 2007, at which I had performed about 20 standard EndoRE (Remote Endarterectomy, LeMaitre Vascular) cases over about two years, this patient in his later 40’s presented to me with ischemic rest pain of his right foot. He was a current heavy smoker who initially had severe claudication and a TASC D occlusion of his right superficial femoral artery. Prior to being referred to me, he had undergone a mitral valve replacement from which he recovered uneventfully. He then had treatment of claudication starting with iliac stenting and a vein bypass. He had undergone a femoral artery to below knee popliteal artery bypass with reversed greater saphenous vein which became occluded after being complicated by MRSA wound infections. When this graft developed problems at the distal anastomosis, he underwent revision with a jump graft from the arm. This graft went down after he developed MRSA infection of the cephalic vein harvest site. He then underwent SFA stenting with 5 femoral stents (at that time, long stents were not available), but these occluded and his access site was the nidus of MRSA based sepsis. He had had multiple hospitalizations for MRSA infection from phlebotomy sites when he presented. He had reintervention for in-stent restenosis, first with balloons, then an extra stent, then cryoballoon therapy, each episode complicated by MRSA infection. He presented with severe claudication and nocturnal rest pain. On exam, he had dependent rubor, elevation pallor and absence of pulses, despite having fairly benign anatomy on CTA.

 

CTA AP

There was two vessel runoff below a reconstituted popliteal artery, with stent occlusion and visible stump of the vein bypass.

CTA medial oblique

My options included bypass with PTFE, cadaveric vein, endovascular recanalization of the occluded stents, or EndoRE. While considering the MRSA which had been extensively worked up prior to presentation by ID including TEE and multiple cultures, it was decided that he was firmly colonized with MRSA despite efforts at eradication, and PTFE was not an option. Cadaveric vein I have used in infections with acceptable short term results -never great long term except for one individual who I inherited from a surgeon in Kansas who maintained a decade of patency of a cadaveric vein to tibial artery bypass with coumadin alone. This patient was not likely to be so lucky. Endovascular recanalization with atherectomy versus laser was considered, but I had at that point become disillusioned with those modalities in such extensive disease.

EndoRE made the most sense because it was my observation in a prior patient in whom I had unintentionally removed a 4cm stent with plaque that stents are placed inside plaques and when you remove plaque, theoretically, the stents have a layer of plaque between them at the adventitia. Also, he had none of the extensive calcium that made regular EndoRE challenging. Also, it would be repaired with native tissues through a single groin incision, and covered with a sartorius flap. And that is what I did.

The common femoral artery was exposed and the SFA controlled. The plaque dissection was started and the ring fitted around plaque and stent. There was a little more friction than expected, but I did inject via a catheter cold LR with the idea that it would shrink the nitinol a bit. Also, the wire that guided the catheter did double duty as a dissector as I was subintimal with it. The rings traveled well to the end point which I achieved with little difficulty.

Vollmer Ring Dissector around plaque & stents
Vollmer Ring Dissector around plaque & stents

ex vivo stents

The end point was dissected and required a short self expanding stent. The patient recovered well and was discharged, but as in prior admissions, developed a cellulitis on the groin wound that resolved with Vancomycin, presumably with MRSA. A CTA done at that admission showed excellent patency and he had palpable pulses.

CTA post oblique with center line

Three years later, he underwent intervention by one of my partners in cardiology at that time for a restenosis in the mid SFA and had ballooning and a stent -the second set of stents in this patient, and by the time I left Iowa, he was still patent and walking.

This operation fails with randomly distributed TASC A lesions that develop in sites of remnant smooth muscle. I think today, I would treat with a drug eluting balloon. Thrombosis is the other failure mode, but unlike PTFE grafts, there is no thromboembolism of the outflow, rather, the SFA thromboses with reconstitution of the original state, and is amenable to thrombolysis. Smokers such as this patient and those with limited outflow are anticoagulated with warfarin.

The Europeans call this now arterial restoration. The vessel is returned to its baseline state with a full complement of collaterals which are revived. Also, compliance is restored and I believe this plays a significant role in maintenance of patency. Also, as the native tissues heal, they return to a normal ultrastructure -I have taken pathology specimen with aortic punches to perform bypasses to the other leg from external iliacs treated so, and they were microscopically and visibly normal.

EndoRE-ABF -an alternative to the EndoABF which is in turn an alternative to the ABF.

  
The patient is 70 year old woman with prior history of smoking who developed severe claudication and near rest pain. She was unable to walk more than 50 feet before having to stop due to severe leg pain. On exam, neither femoral artery pulses were palpable. PVR’s (pulse volume recordings) and ABI’s (ankle brachial index) are shown below.

PVR pre2

PVR’s demonstrate the presence of severe inflow (aortoiliac occlusive disease or AIOD). CTA was acquired and the findings were consistent with the PVR’s.

preop centerline CTA composite

There was diffuse bilateral iliac atherosclerotic plaque with occlusion of the right common femoral artery and left common and external iliac artery. The 3DVR (three dimensional virtual reality) reconstruction image below shows this as well as the abdominal and pelvic wall collaterals feeding the legs around the occluded iliofemoral system.

Pre CTA

Plans were made to perform a hybrid common femoral and profunda femoral endarterectomy, remote external iliac artery endarterectomy (EndoRE), and common iliac artery stenting. The specific challenges to this case was getting into and staying in the true lumen. Typically, this is easiest to achieve from a left arm access with wires being pushed antegrade, but in a smaller person, particularly woman, this increases the chances for access site complications. My plan was to expose both common femoral arteries and get control of the external iliac arteries at the inguinal ligament and the profunda femoral arteries at the point the proximal plaque dissipated -typically at the second branch point, and then get micropuncture access of the right iliac system by accessing from the common femoral plaque. This would give me true lumen access, and with a sheath and curved catheter (VCF in this case, but a similarly shaped OMNI Flush catheter would do as well), wire access up and across the occluded left iliac system could be achieved and the wire retrieved from the left common femoral artery. This up and over access with the wire allows for control of the aortic bifurcation and both iliac systems.

I perform EndoRE over this wire -this allows for quick access if the artery is ruptured. To minimize blood loss, I gain control of the common femoral artery in the following fashion -a 4cm segment of common femoral artery is left intact and looped above the inferior epigastrics -this loop is brought out in the lateral lower quadrant of the abdomen so that the loop doesn’t travel distally over the arteriotomy. The second loop adjacent to the arteriotomy is sent through periadventitial tissues behind the artery to keep the loop migrating over the arteriotomy. The arteriotomy is created from the distal CFA (common femoral artery) onto the profunda femoral artery (PFA) where the endarterectomy is started. A separate arteriotomy on the superficial femoral artery (SFA) allows me to divide the plaque and mobilize the proximal segment up to the SFA origin, freeing the CFA plaque in this manner. It also gives me the option to perform EndoRE of the SFA if warranted. The dissected plaque and system of loops which I call the blood lock is shown below:

  
The yellow loops are major control points (the blood lock loop is drawn in the picture above) and the red loops are around smaller branch arteries. At this point, micropuncture access through the plaque core was achieved into the true lumen of the yet patent EIA (external iliac artery, picture below).

 
The right EIA plaque was mobilized with a Vollmer ring dissector, and cut with a Moll ring cutter (LeMaitre).

 

This allowed for cutting and removal of the plaque. 

  
Up and over access and control of the wire from the contralateral (left) arteriotomy allowed for EndoRE on the other side. The occluded left common iliac plaque was ballooned and wire access into the aorta from the left was achieved. 

  

Kissing balloon angioplasty was performed with revascularization of the aortoiliac bifurcation and common iliac arteries. 

  

The stents were extended across the dissected end points of the external iliac artery origins. The arteriotomies were closed with bovine pericardial patches. Because the PFA were of small caliber, to avoid narrowing the distal end of the patch, the patches were sewn over Argyll shunts which also allowed perfusion of the legs during the suturing of the patches. The loops made this a straighforward maneuver. 

The completed CFA to PFA patch on the left is shown below:

  

Closure involved reapproximating the Scarpa’s type investing fascia of the femoral triangle and a running dermal layer of absorbable monofilament, dressed with a surgical glue. No drains were used, but if needed, they would be exited through the counter incisions created for the EIA loops. 

The patient recovered well. I always use cell salvage -sometimes, profundaplasties can be bloody, particularly if they are in reoperative fields. The ABI’s and PVR’s at the ankles improved significantly.

  The postoperative CTA shows good results as well. Below is the composite right and left centerline from aorta to the PFA’s. 

  
The 3DVR reconstruction images are shown below, with the comparison to preop shown in the first image of this blog entry:

  
The pre and postoperative images of the centerlines (composited) are shown below:

  
EndoABF is an established hybrid procedure involving an open endarterectomy of the common femoral and PFA/SFA with iliac balloon angioplasty and stenting, often taking the stents distally into the CFA and the patch to deal with complex distal EIA plaque. This procedure, which would be an EndoRE ABF, offers some advantages in eliminating the need for EIA stents which are often placed across the inguinal ligament and into the patch during EndoABF. In my experience, the EIA EndoRE performed as an extension of a CFA endarterectomy is safe, and made even safer by performing the EndoRE over a wire. Published results from Europe shows for TASC C and D disease, EIA EndoRE has excellent patency, and I would expect the same here. EndoRE and Endo ABF both offer advantages over traditional ABF, particularly in patients with medical comorbidities. 

  

Should the SFA be revascularized during an inflow procedure?

Sketches - 12

The patient is a 70 year old man who arrived with complaints of worsening claudication, worse on the left leg. He smokes over a pack a day. On exam, he only had femoral pulses, nothing was palpable below. PVR showed multilevel disease with an ABI of 0.42 on the left leg.

PVR preop

CTA was done showing that both his SFA and PFA were occluded, along with occlusion of his AT in the mid leg, and tibioperoneal trunk.

cta TIBIAL_1

There is a reconstitution point on the PFA, and there is also SFA constitution. Looking at this, it was apparent to me that it would be possible to endarterectomize the whole of the iliofemoral and femoropopliteal system from a single groin incision, but the question being, would a profundaplasty be sufficient.

Arrow points to calcium free terminus for SFA EndoRE
Arrow points to calcium free terminus for SFA EndoRE

The textbook answer is profundaplasty, but given my experience with endarterectomy, it has become apparent that removing all the plaque, including CFA and iliofemoral plaque reduces the chance that clamp injury and stenosis occur, and that placed in the common iliac system have better patency than those placed in the external iliac, particularly crossing the inguinal ligament into a patch.

The other observation is that with this exposure, SFA remote endarterectomy is very simple to do, but becomes more difficult in a redo situation. The only problem with going ahead with it is that the runoff is poor -all three tibial vessels occlude, but a very robust posterior tibial artery reconstitutes proximally from well developed collaterals.

The CFA, PFA, and SFA were exposed as shown in my sketch at the beginning of the post. Wire access up and over from the right side allowed for secure control of the aortoiliac segment. The endarterectomy was started from the PFA reconstitution point and the CFA plaque was mobilized. The SFA plaque was transected in a proximal arteriotomy and the plaque was mobilized with a ring to its origin. The CFA plaque then was mobilized with the ring dissector over a wire (for security in case of rupture), up to the EIA origin and cut.

Image-5

The distal SFA plaque was endarterectomized to the planned end point above the knee joint.

Image-4

The specimen is shown below.

specimen

The arteriotomies were repaired with patches. The common iliac artery was stented to improve the flow. The SFA end point was managed with a stent, placed proximal to the first large geniculate collateral.

prepost sfa endpoint

Completion angiograms show widely patent EIA, CFA, PFA, and SFA

Completion

The patient recovered and was discharged on POD#3. His postop ABI’s are shown below.

ABI post2

They are improved compared to preop, with ABI’s of 0.65. Notably, he did have a weakly palpable posterior tibial artery pulse, and multiphasic signals in all three tibial vessels. While I don’t know if the SFA revascularization will stay open, I am confident the PFA will, and this will keep him from his symptoms recurring and is a durable procedure.

Ideally, if he had needed a distal revascularization, a vein bypass would be the answer, but in the setting of inadequate conduit, it is very simple to endarterectomize from the below knee popliteal artery the remaining plaque and either patch to the patent tibioperoneal trunk or perform a short POP to posterior tibial artery bypass. He did not require this.

I don’t know the answer to the titular question, but in the setting of an inflow procedure, the best chance at opening the SFA is during the inflow procedure because of the exposure, and it is very simple to do when the lesion is minimally calcified.

Removing Occluded Stents For Critical Limb Ischemia

Image-22

The patient severe claudication and nocturnal rest pain and had undergone an inflow procedure at another hospital consisting of a common femoral endarterectomy and a single stent to the external iliac artery near its origin from the iliac bifurcation. He also had undergone a concurrent SFA atherectomy which closed and was treated with SFA stents extending from the SFA origin to the above knee popliteal artery. Unfortunately, his rest pain worsened.

ABI2

On exam, he had a femoral pulse only and no distal pulses, only monophonic and weak pedal signals. The right groin wound had been treated for postoperative wound infection and there was still some swelling and a stitch abscess, but no deep infection. CTA showed that his profunda femoral artery had a focal dissection or stenosis at the origin along with overhang of his SFA stents across the origin of the PFA. The SFA stents were occluded along their whole length. There was remnant disease of the external iliac artery as well.

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There was reconstitution of a diseased but patent above knee popliteal artery with three vessel runoff. He had had harvest of his greater saphenous vein. Treatment options included multisegment arm vein with redo profundaplasty, but given the inflammation around his recently operated, recently infected groin, I was concerned for wound infection. He was also quite disabled by his worsened pain. The other option was to access the left common femoral artery and placed a sheath up and over and wire across the diseased profunda and intervene on it, but with the stent in place, I would have to place likely another stent across the origin. I could then attempt a bypass with arm vein or prosthetic graft using this compromised artery as inflow for a bypass to the below knee popliteal artery or a tibial vessel but I doubted this would be durable, nor resistant to infection if prosthetic was used.

Remote endarterectomy (EndoRE) gave me a third option. It is a hybrid technique, but based on an old and established technique of open remote endarterectomy dating from the 60’s. Rings (Vollmer Rings, LeMaitre Vascular) are used to dissect occlusive plaque under fluoroscopy, and a cutting ring (Moll Ring Cutter, LeMaitre Vascular) is used to cut the plaque at the chosen location. Because the distal end point of dissection is not surgically exposed, but rather fluoroscopically guided, it is termed Remote Endarterectomy. Wire skills are required to access and repair any dissections that may occur.

I have presented in the past a series of cases where I removed occluded stents. Because the dissection is carried out outside the plaque, it is also outside the stent. Retrograde EndoRE of SFA plaque can be carried out up to the SFA origin, and avoid a groin incision which in this case was important. Therefore, a proximal thigh exposure of the SFA and EndoRE was planned with endovascular access by left CFA as described.

Photo Apr 15, 10 08 52 AM

The SFA was a hard, calcified pipe and control was achieved with vessel loops which allow passage of the ring and occlusion of the artery once the plaque and stents were removed. The artery was opened via longitudinal arrteriotomy and the plaque mobilized and divided. The proximal SFA plaque was then dissected (above and below).

proximal dissection

There was immediate establishment of a robust pulse in the proximal SFA after removal of the plaque.

Photo Apr 15, 10 14 06 AM

Distally, the plaque would not mobilize at a point in the artery where there was laxity in the artery and especially adherent plaque and therefore, the distal SFA was cut down on to reaccess the stent from below.

Cutdown to reaccess plaque, basically a reversion to the original pre-endovascular technique.
Cutdown to reaccess plaque, basically a reversion to the original pre-endovascular technique.
Mobilizing stent from above and below
Mobilizing stent from above and below
The distal plaque was cut with a Moll Ring Cutter. The removed specimen in total is below.Photo Apr 15, 12 03 16 PM

The arteriotomies were repaired with patch angioplasties using bovine pericardium. This allowed for completing the procedure with endovascular techniques which included the distal end point dissection, profunda stenosis, and external iliac stenosis.

Distal end point managed with self expanding stent.
Distal end point managed with self expanding stent.
PFA

EIA

At completion, there was a palpable dorsalis pedis artery pulse. The composite angio with preop CTA centerline reconstruction are shown below.

completion

He had relief of his symptoms. Prior to discharge, ABI and PVR’s show normalization of flow to his foot.

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Conclusion: In my experience, the longevity of these lesions is dependent on the same factors dictating other revascularizations -excellence of inflow, optimization of profunda outflow, and good tibial outflow. The conduit, being the recanalized original artery, is not as good as a single vein, but it remodels and becomes normal artery based on micro pathology. Failure occurs at the stent with the usual restenosis that can occur in some but not all people, and in isolated points in the artery where likely remnant tissues scar creating focal lesions. Frequent surveillance achieves acceptable primary and secondary patencies. Thromboses do occur. Unlike PTFE grafts, thromboses in EndoRE is usually limited to the recanalized artery without distal embolization. Stent removal is challenging but feasible. In this patient, a second cut down was required to achieve plaque and stent removal. The groin was not re-entered, avoiding dissection in a recently infected, surgical wound. If the popliteal was occluded, a popliteal endarterectomy via a below knee cutdown is possible achieving total femoropopliteal plaque clearance, and the below knee popliteal artery can then be used for a very short bypass to one of the tibial arteries if indicated and if autologous vein is limited in availability.

EndoRE offers a third option after bypass and intervention and should be in a vascular surgeon’s armamentarium.