Category: EndoRE

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EndoRE

An Open Letter to LeMaitre Vascular

George W. LeMaitre, Chairman and Chief Executive Officer, LeMaitre Vascular, Inc.

Dear George,

If you go to the LeMaitre Vascular website, there is a link to the story about the company’s founding by your father, Dr. George Lemaitre, which I heard first hand over dinner hosted by him and your mother many years ago. The original LeMaitre Valvulotome has followed me through my career from surgery residency in the 90’s to a recently closed tenure as vascular chief at Cleveland Clinic Abu Dhabi. There is no in-situ bypass that I perform where I am not struck by your father’s story and by the ideals passed by him into the company he founded which had at its core the desire to help vascular surgeons take care of their patients. There are so many other companies, most of them in fact, in this vascular space who are investor-first when it comes to decisions about what diseases, procedures, and specialties to support, but LeMaitre Vascular has always felt different.

For decades, LeMaitre Vascular seemed focused on helping vascular surgeons care for their patients with unique, purpose-designed solutions. Engineering at its finest. It gave life to many ingenious products like Anastoclip, Unballoon, and LeverEdge, that seemed to spring from the minds of working surgeons and physicians directly into their hands, much like the valvulotome. The best ones appealed to the many surgeons who wanted to advantage their patients and their institutions with both lower cost, time efficiency, and equivalent or better outcomes to the usual way things are done. Unfortunately, we live in a universe where the incredibly potent gravitational pull of the investor interests is for high volume, high margin items. This pull greatly exceeds that of the bright yet smaller stars and moons that are common sense, durability, and sustainability. Items that drop out of peel packs, are used once, and thrown into a landfill, have become everything used in healthcare. The sudden absence of EndoRE (remote endarterectomy) on the LeMaitre product page speaks volumes to this. Something that is low volume, durable, subject to repeat use like a set of Vollmar Rings, which are purchase once and used for a long time, must have little appeal to those who author investor reports. It is in such an decision environment that EndoRE the product must have been cancelled from the LeMaitre Vascular web page (link). I wouldn’t think that LeMaitre would give up manufacturing the eponymous valvulotome for low sales figures, but it did give up on remote endarterectomy for that reason.

Let me show you one of the first cases I did after returning to Cleveland. I am now practicing at Fairview and Avon Hospitals, premier flagship hospitals in the Cleveland Clinic fleet, on Cleveland’s west side, and a patient arrived while I was on call with sudden onset of pain in his leg from a lack of blood flow. He had occlusive atherosclerotic plaque extending from his external iliac artery to the above knee popliteal artery causing ischemic rest pain.

Occluded from external iliac origin to the above knee popliteal artery

I contacted LeMaitre Vascular and got in touch with your representative, L. Fisher, who promptly sent the Moll Ring Cutters I needed to perform a remote endarterectomy of the patient’s occlusive external iliac and superficial femoral artery plaque. The technical details of remote endarterectomy are have been covered in my blog (https://vascsurg.me/?s=endore), but in the end, through a 7cm incision in the groin (don’t believe the hype, this is minimally invasive), I restored his arteries to their original open condition. Shown below are the results. It was with great sadness that I heard that the LeMaitre Vascular equipment being sent were the last of the stock available in North America. The patient did very well, with the operation completed well before lunch, and is recovering rapidly from his small wound and big rescue. He gets to walk out of the hospital on two legs, but also with the surety that he avoided a major bypass operation, and avoided the short term gains of stenting from the aorta to the profunda -more peel packs and landfill items and a dubious long term durability. Hey, I even used a XenoSure patch on the common femoral.

The patient’s arteries from external iliac artery in the pelvis to the above knee popliteal artery at the knee are restored to patency
The plaque from the external iliac artery has been removed with a Moll Ring Dissector
This was done in a regular operating room with portable imaging equipment. On the right is the plaque, nearly half a meter extracted from the patient who now has palpable pulses in his foot.

Endarterectomy is foundational to vascular surgery going back to the work of Professors J. Cid Dos Santos and E. Jack Wiley. Through Dr. Kenneth J. Cherry, who trained under Dr. Wiley, and who trained me, I can claim two degrees of separation from the originator of endarterectomy, and this drives my passion for preserving this critical tool in our vascular kit. The basic tools, the endarterectomy rings, are as old as vascular surgery itself. To lose a critical supplier, particularly in a time when the pendulum to open surgery is swinging back, when the best results come from combining traditional surgery and cutting edge endovascular techniques in hybrid procedures such as EndoRE, when the coming healthcare cost-apocalypse will cause everyone to question the value of thousand dollars-plus items dropped from peel packs, is devastating.

I get it that the aSpire stent never panned out, and that disposable dissector/cutters never moved that well, and that you run a business, not a charity. But I do believe that best companies reflect the best values of their people, such as the prompt action and followup of your rep L. Fisher who by getting us the rare supplies, helped in achieving this patient’s excellent results. While I believe there is a business case to be made in preserving and relaunching EndoRE, as endarterectomy has proved to be future proof for nearly a century, I believe more strongly that it is the right thing to do.

Sincerely

W. Michael Park

Categories
AIOD aortoiliac occlusive disease (AIOD) bypass Commentary EndoRE opinion ultrasound

Arterial Restoration in CLTI with Remote Endarterectomy (EndoRE).

preop PVR

The patient is a man over 70 years of age who came to the hospital with severe pain of his right foot and leg with walking short distances and at night while recumbent. He had a history of hypertension, diabetes, and coronary artery disease, and several years ago had his left common iliac artery stented. On examination, he had no lesions of his foot, and his pulses were only palpable (barely) in the femoral arteries only. He did have strong monophasic signals in the anterior tibial arteries bilaterally.

Initial vascular lab testing showed only mildly depressed ankle brachial (above), with dampened waveforms consistent with inflow and femoropopliteal disease on the right. He underwent arteriography by our vascular medicine specialist and cardiologist Dr. Faisal Hasan, and it showed bilateral common iliac stenoses, a severely calcified and nearly occlusive plaque in the right common femoral artery, and a long segment occlusion in the superficial femoral artery with diffuse calcified plaque extending into the popliteal artery. There was diseased but patent 3 vessel tibial runoff.

aortogram

R SFA arteriogram

To Act As A Unit are the Cleveland Clinic’s words and it shows the Clinic’s roots as an US Army field hospital on the vasty fields of World War I France a little over a century ago, and we take it seriously. It may come as a surprise to some that a cardiologist referred me this patient after mutually deciding that the common femoral disease and the TASC D SFA occlusive disease, but we both decided that a surgical approach was the best one. The question then is how much more flow?

I ordered a CTA (CT angiogram) particularly for endarterectomies as I find it imperative to know the actual end point of plaque. Arteriography only hints at it, and while a 5mm lumen may look large and patent, it may be a channel in a 10mm wide plaque that when a stent terminates within it, breaks and becomes biologically active as intimal hyperplasia at best or embolizes at worst. CTA shown below revealed the plaque where contrast angio showed only the lumena of the vessels.

The 3D reconstruction function also allowed me to see and plan the operative approach and predict the lack of saphenous vein confirmed on duplex ultrasound.

For the students reading this, ischemic rest pain is often simpler to treat because it requires only a little more blood flow. There is a neurologic ischemia component that is not well studied, particularly in diabetics, as ischemia may result in anesthesia in someone who has underlying diabetic neuropathy, but that is not an indication for revascularization while rest pain is, and someone should investigate this. This little more blood flow in the form of treating inflow disease only may be sufficient in relieving rest pain while avoiding interventions on the superficial femoral, popliteal and tibial arteries which have limited longevity.

The common femoral artery on the other hand is the throttle of inflow and as a principle, inflow can be considered as the infrarenal aorta to profunda femoral artery, and repairing the common femoral necessitates an operation. There is no durable or laudable endovascular procedure for occlusive disease of the common femoral artery, a feature shared with the subclavian artery at the thoracic outlet and the celiac axis at the median arcuate ligament. All three are externally compressed by hard structures and revascularization must be ever mindful of the inguinal ligament, the thoracic outlet, and median arcuate ligament. The only exception to the “you must operate” rule of the CFA is calcified atherosclerotic disease in high risk individuals, and I make careful exception here with rotational atherectomy devices.

Claudication is another thing entirely. Claudication limits lifestyle and can be corrected by changing lifestyle -either with more exercise or limiting exercise. The thing is, when a patient has reached a certain age, that lifestyle may be walking slowly from chair to commode, and if that activity is limited, no amount of haranguing may be able to induce that person to embark on an ambitious exercise program. Sometimes, you have to be realistic about telling a frail old man to go for a 60 minute walk. But if that person has difficulty getting to the bathroom because of leg cramps, then either they have to get assistance or more bloodflow, and ironically, a little more blood flow represented by improving inflow, may not be enough.

That was what I was thinking when I was planning this operation. Improve the inflow with stents to the common iliacs and a right CFA endarterectomy, but use the opportunity of surgical exposure to extend the endarterectomy to the distal external iliac and through the entire SFA.

My fondness of remote endarterectomy is well known from my many blog posts on it (link). It is a modern update on a very old procedure -the ring endarterectomy, done since the middle of the last century when bypass grafts were unavailable. The occlusive plaque is removed, and an end-point reached and cut with a scissor like device (available from LeMaitre). It is the ultimate hybrid operation (below) requiring open and endovascular skills. I tell prospective trainees to judge training programs by how facile are the surgeons and how many are the procedures with and involving a hybrid approach, because any program can have few (getting fewer) old surgeons doing only open surgery and a lot of young surgeons doing only endovascular procedures, but a rare few will do a lot of hybrid procedures. endore-graphic.jpg

I chose to add femoral EndoRE. This would bring the extra blood flow needed to kickstart any walking program, barring cardiopulmonary limitations.

The patient was brought to our hybrid operating theatre and prepped from nipples to toes. The right common femoral artery was exposed for endarterectomy, and accessed then with a sheath along with a left femoral sheath for kissing balloon angioplasty and stenting of the common iliac artery stenoses (below).

preinterventionpost kissing stents

Afterword, the CFA was opened and endarterectomized, and the SFA was remote endarterectomized (below).

EndoRE setupEndoRE

The endpoint was chosen in the above knee popliteal artery to avoid having to stent the dissected end point plaque well into the popliteal artery. If I wanted to go all the way to the below knee popliteal artery, I would have to open it to manage the plaque and artery at the so-called trifurcation, typically with a patch angioplasty. The plaque came out in one piece (below):

EndoRE plaqueplaque in toto

The terminus of the plaque in the POP where it was cut has to be managed with a stent, unless you open and complete the endarterectomy and patch the artery. I was able to cross the dissection (no small feat) and plaque a stent. The artery was widely patent and even the small branches off the previously occluded SFA were now reopened.

Endpoint managementbefore and after endoRE

His pulse volume recording done after intervention reflects the improved flows (below).

PVR before and after

His rest pain resolved, but more gratifyingly, he has regained the confidence to walk and exercise, which he now does without limitation up to 45 minutes a day. In two month followup, we performed a duplex which showed his right SFA to be basically normal (below), including an intimal stripe and media. This is not an anomaly. When I took a punch out of restored artery to perform an anastomosis (from this case link), I sent it. Previously it had been an artery that was obstructed for nearly a decade, but after EndoRE, had become an elastic, compliant vessel. The pathology returned as “normal artery.”

postop duplex at 2 months

When these fail, they typically do so a random points on the endarterectomized vessel and on the stent. While stent grafting may have better outcomes with regard to restenosis, doing so covers collateral vessels and PTFE grafts behave poorly by embolizing while clotting off, and PTFE stent grafts are no different. Data from over a decade ago suggests that EndoRE of the SFA while inferior in patency to vein grafts, are equivalent to PTFE [reference 1] and superior to endovascular revascularization [reference 2] in terms of primary patency. When they occlude, they achieve a “soft landing” without the furious acute ischemia and embolization seen with PTFE bypasses.

I think these handful of cases I performed here in the UAE represent the first in the region. The main difference here is that the arteries tend to be smaller by about 20%, and in one instance, the smallest Vollmer ring was too large for the vessel in a case where I abandoned the SFA revascularization -the profunda and inflow revascularization proved sufficient in reversing rest pain. The intriguing property of endarterectomy is something that we all try to do with surgery but rarely achieve -a restoration to an earlier time. I believe this patient’s right femoral artery is now back to a youthful state.

References:

  1. Eur J Vasc Endovasc Surg 2009;37: 68-76

  2. J Vasc Surg 2012;56:1598-605.
Categories
AIOD amputation aortoiliac occlusive disease (AIOD) BKA bypass complications EndoRE innovation PAD remote endarterectromy techniques Wounds

Arterial Restoration -Something New, Something Old

Something that I recently promised Dr. James S.T. Yao, I will be working to publish on my stent removal and extended remote endarterectomy cases and techniques. Meanwhile, here is a talk.

Categories
AIOD aortoiliac occlusive disease (AIOD) BKA bypass CTA EndoRE EVAR graft infection imaging remote endarterectromy

The Unclampable: Strategies for Managing a Heavily Calcified Infrarenal Aorta

Leriche Syndrome -one of those disease names that adds to our work in a way that an ICD codes and even the “aortoiliac occlusive disease” fails to describe. When I hear someone described as having Leriche Syndrome, I think about a sad, chain smoking man, unmanned, complaining of legs that cramp up at fifty feet, pulseless.

The CT scan will occasionally show an aorta ringed by calcium in the usual places that are targetrs for clamping below and above the level of the renal arteries. Even without the circumferential calcium, a bulky posterior plaque presages the inability to safely clamp the aorta. Woe to the surgeon who blithely clamps a calcified lesion and finds that the rocky fragments have broken the aorta underneath the clamp! The first way to deal with this is to look for ways not to clamp the aorta, by planning an endovascular procedure, but circumstances may necessitate the need to control the aorta despite the unclampability.

The traditional methods of avoiding clamping the calcifed peri-renal aorta are extra-anatomic bypasses including femorofemoral bypass and axillo-femoral bypass. I propose these following options for the consideration when the patient needs a more durable solution while avoiding a heavily diseased aorta.

Not Clamping I:

EndoABF.png
An EndoABF (actually EndoRE-ABF)

EndoABF does work to avoid clamping -these are common femoral endarterectomies supplemented by stenting of the aortoiliac segment, including in those with appropriate anatomy, a bifurcated aortic stent graft. This is often not possible to treat both sides, but one side is usually more accessible. Often, people will compromise and perform an AUI-FEM-FEM, but I have found the fem-fem bypass to be the weak link, as you are drawing flow for the lower half of the body through a diseased external iliac artery. The orientation of the proximal anastomosis is unfavorable and in the instance of highly laminar or organized flow, the bypass is vulnerable to competitive flow on the target leg, leading to thrombosis.

auifemfem.png
AUI prior to fem-fem bypass for acute aortoiliac occlusion causing critical limb ischemia

The femorofemoral bypass is the option of patients whose options have largely run out. It is made worse when fed by an axillofemoral bypass. Sometimes, you have no choice, but in the more elective circumstance, you do.

 

Not Clamping II:

The second method is performing a aorto-uni-iliac stent graft into a conduit sewn end to end to the common iliac aftery, oversewing the distal iliac bifurcation.

conduit.png

The conduit is 12mm in diameter, the key is to deliver the stent graft across the anastomosis, sealing it. The conduit is then sewn to the side of a fem-fem bypass in the pelvis, maintaining antegrade flow to both legs. The other option is to sew the conduit to a 14×7 bifurcated graft. Illustrated above is this 12mm conduit sewn end to end to the diseased common iliac artery with wire access into the aorta and a aorto-uni-iliac device. Typically, a small AUI converter (Cook, Medtronic) can be used, but the aorta is often too small even for a 24mm device, and an iliac limb with a generous sized docking segment (Gore) ending in a 12mm diameter fits nicely. Below is a CTA from such a case, where the stent graft is deployed across the anastomosis, sealing it off from anastomotic leaks (exoleaks).

AUI fem fem.jpg

Not Clamping III:

Often, the infrarenal aorta is soft anteriorly and affected only by posterior plaque at the level of the renal arteries. While a clamp is still not entirely safe (I prefer clamping transversely in the same orientation as the plaque with a DeBakey sidewinder clamp), a balloon is possible. I do this by nicking the aorta -simple application of a finger is sufficient to stop the bleeding if you have ever poked the ascending aorta to place cardioplegia line.

conduit1.png

A Foley catheter is inserted and inflated. The Foley’s are more durable and resist puncture better than a large Fogarty. This is usually sufficient for control, although supraceliac control prior to doing this step is advised. The aorta can be endarterectomized and sewn to the graft quite easily with this non-clamp. conduit2.png

This has worked well, Although pictured above with an end-to end anastomosis planned, it works just as well end-to-side. I actually prefer end to side whenever possible because it preserves the occluded native vessels for future intervention in line.

The Non-Thoraco-Bi-Femoral Bypass

The typical board answer for the non-clampable aorta is taking the inflow from the thoracic aorta or from the axillary artery -neither of which are good options. The first because the patient is positioned in right lateral decubitus and tunneling is not trivial. The second because of long term durability. The supraceliac aorta, technically it is the thoracic aorta, is often spared from severe plaque and clampable. Retropancreatic tunelling is straightforward, and a 12 or 14mm straight graft can be tunelled in this fashion from the lesser sac to the infrarenal retroperitoneum. It then sewn to the supraceliac aorta and then anastomosed to a 12x6mm or 14x7mm bifurcated aorto-bifemoral bypass, of which limbs are tunneled to the groins.

Sketch134215736.jpg

This worked very well recently, allowing a middle aged patient with severe medical problems, occluded aorta and iliac arteries, with critical limb ischemia, survive with minimal blood loss and home under 5 days. It delivers excellent flow to both legs in an antegrade fashion. Dr. Lew Schwartz gave me a list of references showing that this is not novel, but represents a rediscovery as the papers were published in the 80’s [reference], and buttresses the principle that innovations in open vascular surgery are exceedingly rare, largely because we have been preceeded by smart people. 

Conclusion: All of these come about through application of some common sense and surgical principles. The most important this is that the aorta is the best inflow source and reconstructing it with the normal forward flow of down each leg and not reversing directions as in a fem-fem bypass gives each of these options a hemodynamic advantage.

 

References for Supraceliac Aorta to Lower Extremity Bypass

  1. Surgery [Surgery] 1987 Mar; Vol. 101 (3), pp. 323-8.
  2. Annals of Vascular Surgery 1986 1(1):30-35
  3. Texas Heart Institute Journal [Tex Heart Inst J] 1984 Jun; Vol. 11 (2), pp. 188-91.
  4. Annals of Thoracic Surgery 1977 23(5):442-448
Categories
AIOD aortoiliac occlusive disease (AIOD) complications EndoRE graft infection limb salvage remote endarterectromy techniques Uncategorized

Salvage: A different approach to graft infections in the groin

The principles of salvage are in rescuing valuable undamaged goods in the setting of catastrophe. This guided me when a patient was flown in from an outside institution to our ICU with a saline soaked OR towel in his right groin -he had had an aorto-bifemoral bypass for aorto-iliac occlusive disease a year prior, but had never properly healed his right groin wound which continued to drain despite VAC therapy and wound care. On revealing his groin, this is what I saw:

EndoRE in graft infection.002

A CT scan was sent with the patient but has been lost to time, and it showed a patent aorto-bifemoral bypass send flow around an occluded distal aorta and iliac arteries. The graft did not have a telltale haze around it nor a dark halo of fluid which signaled to me that it was likely well incorporated and only sick in the exposed part. The patient was not septic, but had grown MRSA from the wound which was granulating from the extensive wound care that had been delivered.

EndoRE in graft infection.009

I felt that it would be possible to move his anastomosis point more proximally on the external iliac in a sterile field (figure above), and then close, then endarterectomize the occluded external iliac artery after removing the distal graft, then after vein patching, cover the repair with a sartorius muscle flap. It would salvage the remaining graft and avoid a much larger, more intense operation which was plan B. To prepare for that, I had his deep femoral veins mapped.

The patient was prepped and draped, the groin was excluded by placing a lap pad soaked in peroxide/betadine/saline solution (recipe for “brown bubbly” liter saline, a bottle of peroxide, a bottle of betadine), and covering with an adesive drape. The rest of the abdomen was then draped with a second large adhesive drape. A retroperitoneal (transplant-type) right lower quadrant incision was made (below) and the external iliac artery and graft were exposed. As predicted on CT, the graft was well incorporated.

EndoRE in graft infection.003

The external iliac artery was opened and focally endarterectomized of occlusive plaque (image below). The adventitia had good quality despite the longstanding occlusion.

EndoRE in graft infection.004

The graft was mobilized and transected and anastomosed end to side to this segment of artery (below). Dissecting was made difficult by how well incorporated it was.

EndoRE in graft infection.005.jpeg

The wound was irrigated (with brown bubbly) and closed, dressed, and sealed over with the adhesive drape. The groin wound was then revealed and the graft pulled out (below).

EndoRE in graft infection.006

Remote endarterectomy using a Vollmer ring was used -in this case I didn’t use fluoroscopy given the short distance to the terminus of the plaque which i had mobilized in the pelvis.

EndoRE in graft infection.007

The plaque came out easily and was not infected appearing. It is shown below ex vivo.

EndoRE in graft infection.008

A segment of saphenous vein was harvested from the patient medially and the arteriotomy was patched. The sartorius muscle was mobilized and applied as a flap over this. The wound was irrigated with brown bubbly and packed open with the intention of VAC application.

The patient healed very rapidly and remains infection free. I had used this approach on several occasions in the past and twice more recently. It truly is salvage as it preserves the uninfected graft while never exposing it to the infection in the process of operating. It avoids having to remove the whole graft which then damages the left side -I have seen other surgeons take this approach elsewhere taking a all-or-nothing approach to graft infection to considerable morbidity to the patient. It avoids having to harvest deep femoral vein -another large operation to which the body responds truculently. The patient recently came by for his 4 year followup, still smoking, but legs preserved.

Followup At 4 Years

IMG_0657

The patient came back in followup -it has been 4 years since his infection was repaired. He was complaining of short distance claudication. His wound healed well and remains closed. CTA shows along with his short segment SFA occlusion which we will treat, a widely patent R. EIA (below).

CTA 4 year followup

The remote endarterectomy of the external iliac artery remains patent. Compare this to the preop CTA which I found and wasn’t available when I posted this case originally:

 

preop CTA_4

The chronically occluded EIA can be readily seen. The artery shown in the current CTA is that recanalized artery.

 

Categories
AAA AIOD aortoiliac occlusive disease (AIOD) bypass Commentary EndoRE EVAR imaging kidney transplant remote endarterectromy techniques

When both iliac systems are occluded below an abdominal aortic aneurysm: hybrid techniques on the cutting edge

preop CTA EVAR-ENDORE.jpg
AAA with iliac arterial occlusion -arrows point to right external iliac and left common iliac arterial occlusions

The patient is an 70 year old man referred for evaluation of claudication that occurred at under a block of walking. He reported no rest pain or tissue loss. He smoked heavily up to a pack a day, with congestive heart failure with an ejection fraction of 40%, prior history of myocardial infarction treated with PTCA, and pacemaker, and moderate dyspnea on exertion.

On examination, patient had a flaccid abdomen through which the AAA could be palpated, and he had no palpable femoral artery pulse bilaterally, nor anything below. He had a cardiac murmur and moderate bilateral edema. Preoperative risk evaluation placed him in the high risk category because of his heart failure, coronary artery disease, and his mild to moderate pulmonary disease.
CTA (pictured above and below) showed a 5.1cm infrarenal AAA with an hourglass shaped neck with moderate atherosclerosis in the neck, an occluded left common iliac artery with external iliac artery reconstitution via internal iliac artery collaterals, and a right external iliac artery occlusion with common femoral artery reconstitution. There was calcified right common femoral artery plaque.

Preop left and right centerlines EVAR-ENDORE.jpg

Treatment options included open surgical aortobifemoral bypass with exclusion of the AAA, total endovascular repair with some form of endo-conduit revascularization of the occluded segments of iliac artery, or a hybrid repair.

Open aortic repair in patients with heart failure and moderate COPD can be performed safely (ref 1). Dr. Hollier et al, in the golden age of open repair, reported a 5.7% mortality rate operating on 106 patients with severe category of heart, lung, kidney, or liver disease.

Typically, the hybrid repair involves sewing in a conduit to deliver the main body of a bifurcated or unibody stent graft when endovascular access is not possible. Despite techniques to stay minimally invasive -largely by staying retroperitoneal, this is not a benign procedure (ref 2). Nzara et al reviewed 15,082 patients from the NSQIP database breaking out 1% of patients who had conduit or direct puncture access.

Matched analyses of comorbidities revealed that patients requiring [conduit or direct access] had higher perioperative mortality (6.8% vs. 2.3%, P = 0.008), cardiac (4.8% vs. 1%, P = 0.004), pulmonary (8.8% vs. 3.4%, P = 0.006), and bleeding complications (10.2% vs. 4.6%, P = 0.016).

Despite these risks, I have performed AUI-FEM-FEM with good results with the modification of deploying the terminus of the stent graft across an end to end anastomosis of the conduit graft to the iliac artery (below), resulting in seal and avoiding the problems of bleeding from the usually heavily diseased artery

AUI fem fem.jpg
Aorto-uni-iliac stent graft across end to end conduit anastomosis to fem-fem bypass

The iliac limbs of some stent graft systems will have proximal flares and can be used in a telescoping manner to create an aorto-uni-iliac (AUI) configuration in occlusive disease. The Cook RENU converter has a 22mm tall sealing zone designed for deployment inside another stent graft and would conform poorly to this kind of neck as a primary  AUI endograft which this was not designed to act as. The Endurant II AUI converter has a suprarenal stent which I preferred to avoid in this patient as the juxtarenal neck likely was aneurysmal and might require future interventions

I chose to perform a right sided common femoral cutdown and from that exposure, perform an iliofemoral remote endarterectomy of the right external iliac to common femoral artery. This in my experience is a well tolerated and highly durable procedure (personal data). Kavanagh et al (ref 3) presented their experience with iliofemoral EndoRE and shared their techniques. This would create the lumenal diameter necessary to pass an 18F sheath to deliver an endograft. I chose the Gore Excluder which would achieve seal in the hourglass shaped neck and allow for future visceral segment intervention if necessary without having a suprarenal stent in the way. I planned on managing the left common iliac artery via a percutaneous recanalization.

The patient’s right common femoral artery was exposed in the usual manner. Wire access across the occluded external iliac artery was achieved from a puncture of the common femoral artery. Remote endarterectomy (EndoRE) was performed over a wire from the common femoral artery to the external iliac artery origin (pictures below).

File Mar 31, 13 41 31.jpeg
External iliac to common femoral artery plaque removed with Moll ring cutter (LeMaitre Vascular) over a wire

The 18F sheath went up with minimal resistance, and the EVAR was performed in the usual manner. The left common iliac artery occlusion was managed percutaneously from a left brachial access. The stent graft on the left was terminated above the iliac bifurcation and a self expanding stent was used to extend across the iliac bifurcation which had a persistent stenosis after recanalization.

The patient recovered well and was sent home several days postprocedure. He returned a month later with healed wounds and palpable peripheral pulses. He no longer had claudication and CTA showed the aneurysm sac to have no endoleak (figures below).

post CTA EVAR-ENDORE

postop centerline EVAR-ENDORE
Composite imaging showing normal appearing right iliofemoral segment (EIA + CFA) and patent left common iliac artery.

Discussion
I have previously posted on using EndoRE (remote endarterectomy) for both occlusive disease and as an adjunct in EVAR. Iliofemoral EndoRE has excellent patency in the short and midterm, and in my experience has superior patency compared to the femoropopliteal segment where EndoRE is traditionally used. This case illustrates both scenarios. While the common iliac artery occlusions can be expected to have acceptable patencies with percutaneous interventions, the external iliac lesions typically fail when managed percutaneously especially when the stents are extended across the inguinal ligament. The external iliac artery is quite mobile and biologically, in my opinon, behaves much as the popliteal artery and not like the common iliac. Also, the common femoral arterial plaque is contiguous with the external iliac plaque, making in my mind, imperative to clear out all the plaque rather than what can just be seen through a groin exposure.

On microscopy, the external iliac artery is restored to a normal patent artery -I have sent arterial biopsies several months after endarterectomy and the artery felt and sewed like a normal artery and had normal structure on pathology. This implies that the external iliac can be restored to a near normal status and patients that are turned down for living related donor transplantation of kidneys can become excellent recipients. In this case, this hybrid approach effectively treated his claudication but also sealed off his moderate sized AAA while not precluding future visceral segment surgery or intervention with a large suprarenal stent.

 

Reference

  1. Hollier LH et al. J Vasc Surg 1986; 3:712-7.
  2. Nzara R et al. Ann Vasc Surg. 2015 Nov;29(8):1548-53
  3. Kavanagh CM et al. J Vasc Surg 2016;64:1327-34
Categories
EndoRE EVAR kidney transplant remote endarterectromy techniques TEVAR

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).

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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.

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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.

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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.

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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.

 

Categories
bypass EndoRE PAD remote endarterectromy techniques

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.

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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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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.

Categories
bypass EndoRE PAD tibial revascularization

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

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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.

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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.

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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.

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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.

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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.

Categories
EndoRE PAD remote endarterectromy

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.