Categories
AAA EVAR open aneurysm surgery

Abdominal Aortic Aneurysm in Remission

Look again, it is a doodle of a CT scan of a patient with an Ancure stent graft with sac shrinkage

I remember in the mid-2000’s, driving very fast to Lutheran Hospital in Des Moines on a Saturday night to fix an aneurysm that had ruptured. He was a man over 70 years of age with a type III endoleak from a component separation. The endografts had been placed by a cardiac surgeon who had taken some courses. I rescued him by open replacement of the aneurysm with a tube graft after I pulled out the endografts. Later, as the patient recovered, I asked him why he never followed up as required on his stent graft. His answer was, in typical Iowa farmer fashion, “Welp. If it was fixed, why should I?”

Indeed, why should he? Looking at his chart from the time of his EVAR, he was determined to be a “high risk” patient, necessitating the new minimally invasive procedure EVAR in 2003. Seeing that he survived the stress test of a ruptured aneurysm, it was clear he was not all that “high risk.” I did reassure him that with the open repair, he was basically cured. Despite scheduling a followup appointment, he never showed up. And that was okay.

EVAR is a treatment for AAA, but currently not a cure. All of the devices instructions for use stipulate the need for lifelong followup with CT scans with contrast and visits with qualified specialists. As I have mentioned in the past, what other condition requires surveillance CT scans with contrast and followup with a specialist? Cancer in remission. For those with good cardiac risk and functional status, placing an endograft rather than open repair creates “Aortic Aneurysm in Remission.” If they are in the majority of patients with a stable aneurysm sac, their endografts are sitting in a bag of static, aging blood. If there are type II endoleaks, and it is my belief that the majority of stable aneurysm sacs have some type II endoleaks that blinker on and off depending on the hemodynamics, particularly through needle holes, they are circulating the products of breakdown of that bag of old blood and exposing a perfect culture medium to potential inoculation. These type II and IV endoleaks can inflate the aortic sac over time. Occasionally, the residual AAA sacs rupture, erasing any of the early advantage conferred by the minimally invasive index procedure in long term followup EVAR v OPEN repair.

What is a cure? A cure is when you quell an infection with an antibiotic. A cure is when you’ve taken out an inflamed appendix. It’s when you’ve eradicated early stage cancer. It’s when you perform an open aortic graft and the patient can disappear after you remove the dressings and never followup, sure in the knowledge that the aneurysm in that spot will never bother them again. With EVAR, only a minority get to the state (figure at top) a sac shrunk intimately around the endograft. Most are not cured but enrolled in a regime of lifelong surveillance and maintenance.

EVAR does allow people to leave the hospital with less scarring and pain, but the consequences of its popularity are:   

1. Letting more practitioners, not all of them vascular surgeons, treat aortic aneurysm disease with less training and with less or no ability to manage the inevitable failures surgically. 

2. Creating the business model for “Advanced, Minimally Invasive, Super-Fantastic Aortic Centers of Excellence” which is predicated on the business of surveillance and maintenance of aortic endografts. It is a busy-ness that generates revenue, but burdens the country with more healthcare costs. It ultimately siphons business away from true centers of excellence involved in training the next generation of vascular surgeons.

3. Skewing the training curriculum of trainees to endovascular so much that I have met vascular surgeons who have done no aortic operations. That was the case when I sat in on an open aortic surgery class at the 2017 ESVS meeting in Lyons, France. All the attendees were very eager to try sewing anastomoses, but felt they needed proctoring which isn’t available.

4. Establishing the expectation that open aortic surgery is a failed, antiquarian, obsolete technique to be relegated to the history books. This last one is infuriating and not true but it is out there in the claims of the aorticians.

5. Resulting in palliation when the aortic aneurysm in remission ruptures and there are no readily available open-capable surgeons experienced in rescuing these patients. This happens. Don’t let it happen to you.

Various solutions have been broached including regionalization of aortic aneurysm care, superfellowships in exovascular surgery to complement the widespread endovascular training, and going back to open aortic surgery as the norm as had been proposed controversially in the UK. There is no turning back the clock. The moment that Dr. Parodi combined an aortic graft with Dr. Palmaz’s stent, a quantum leap occurred. The operation of aortic aneurysm surgery was changed from a challenging operation mastered by a few to a straightforward procedure performed by many.

Interesting to me is that illustration at the top of the post is of a common observation – the obliteration of the aortic aneurysm sac around a Guidant Ancure stent graft. When the sac disappears, it is as close to a cure that you can get. For some reason, I see this more frequently with Ancure than with other grafts over the past twenty years.

Odd fact -I may have been the last surgeon to implant an Ancure in the world. In 2003, I was treating a AAA with an Ancure graft when the delivery system froze in mid deployment. I called Dr. Dan Clair away from some meeting, and he called for pliers, screw drivers, and a saw, and after deconstructing the delivery system, deployed the graft and returned to his meeting with nary a word. The Guidant rep, who had been on the phone, looked up with saucer eyes, and said, “Wow. They’ve pulled Ancure off the market.”

I think it is because of the design, which is now off the market. When stents are sewn to cloth, the needle holes leak, and leak particularly where the stent graft makes a turn, stretching the suture hole. Junctions and seams leak. The Ancure, aside from the stents at top and bottom in the seal zone, has no such holes as it is unsupported and manufactured as a single piece with no junctions or seams. It is the closest you get to sewing in a graft by open surgery. If it weren’t for its overly complicated delivery system which was its downfall, I think it would be in its third generation with visceral branches that are created off the textile machines rather than joined inside the patient. There are lessons to be learned from this abandoned tech.

I believe a treat once and walk-away cure is achievable in EVAR. The idea is not to be satisfied with anything less than a cure, anything that ends with aortic aneurysm in remission. We have to understand we have chosen a path of iteration and continuous but slow improvement in the EVAR space. The front end benefits of EVAR are clear but it is in the long term we have to focus. Until then, warranties would be great.

Categories
AAA Commentary common iliac artery aneurysm complications CTA EVAR innovation ruptured AAA techniques training

Lifelong surveillance after EVAR -is it worth it?

About ten years ago, I had a patient who came to see me for moderate carotid disease. While his carotid disease was asymptomatic, he also had metastatic colon cancer. With colectomy, cryoablation of liver mets, and chemotherapy, he was in remission. Every 6 to twelve months he had some kind of CT scan with contrast. His renal function was poor and this was blamed on his chemotherapy. While it had nothing to do with this patient, I thought to myself, “Having an aortic stent graft was a lot like having metastatic cancer in remission.” After a stent graft, the patient is forever tied to the health care system. Without surveillance, there may be an endoleak, sac expansion, rupture, and even death. Patients and vascular surgeons can make choices that lengthen life, improve its quality, and avoid the complications of disease. But what if a treatment becomes a condition and a burden on healthcare resources and the patient’s finances?

Fool me once…

Type Ib Endoleak Causing re-Rupture of a previous r-AAA after no surveillance

Take this patient who had previously ruptured his AAA and undergone EVAR. Several years out from his rupture, he ruptured again from a type Ib endoleak due to aneurysmal degeneration of his right common iliac artery. Per his family, he never followed up. Perhaps he assumed he was cured of his disease? Repairing this was tricky, primarily because I hopped up and down, thinking, “I could cure this!” An open revision with a bifurcated graft would eliminate the need for EVAR surveillance, avoid abdominal compartment syndrome, and the physiologic consequences of a large retroperitoneal hematoma. But who wants a laparotomy? Not this patient, who was hypovolemic shock, and whose family chose the minimally invasive option that everyone assumes is better.

Not a clamp

I took him to the hybrid operating room, balloon occluding to stabilize his blood pressure, embolizing the normal internal iliac artery and extending the stent graft into the external iliac artery.

Completion -there is an Amplatzer plug in the right internal iliac artery

This patient stabilized and had abdominal tightness due to his large hematoma which did not need evacuation. After a stay lengthened by concern for abdominal compartment syndrome, moderate pain, fevers, and bilirubinemia (due to the hematoma), he was discharged and never showed up for followup. None of the phone numbers work. Without followup, EVAR is a menace. We will keep trying.

Regrets, I’ve Had a Few…

The great feature of EVAR is that the complications up-front at the time of surgery are wonderfully low. This patient pictured above here presented in middle age with a rupture into the retroperitoneum. He was unconscious and had hemorrhagic shock.

The decision to perform EVAR was made late in the transfer because I did not have the images from the transferring hospital (another subject for another blog post) so I set up for both open repair and EVAR. En route to the OR, I scanned, slowly, through the CT images sent via CD-ROM, and my internal discussion went something like this.

He’s a 50-something smoker in shock with a contained rupture of a 8cm infrarenal AAA with a good neck. Let’s take care of this in 30 minutes with a percutaneous endovascular aneurysm repair (p-EVAR).”

He’s a 50-something smoker in shock with a contained rupture with a good neck -let’s take care of this in 90 minutes with a tube graft, open aortic repair (OAR).”

With p-EVAR, he’s going to have just two groin punctures and much lower complication rate, shorter length of stay, similar to lower mortality. Look -his blood pressure is 75mmHg systolic!

That hypotension is permissive to minimize bleeding. With OAR, he’ll avoid abdominal hypertension and complications of a giant hematoma. Because he’s young, he’ll avoid lifelong surveillance. If anyone can clamp this AAA, it’s me...”

Pride cometh before the fall. Get this man off the table and figure out the logistics later. p-EVAR. You open him up, he’ll exsanguinate and expire before you get the clamp on.

I sighed, looked up at the gathered team, and announced, “p-EVAR.” The percutaneous EVAR is something I’ve been doing since 2004, long before it was a big deal, and we were done under an hour. His blood pressure stabilized, but general surgery was consulted for his abdominal compartment syndrome. With sedation, fluids and time, his urine out put recovered but his belly remained distended and his bladder pressures which were never seriously elevated, trended down.

It was made known to me that the patient had very limited insurance making followup surveillance challenging. Due to his coverage, he had to have his imaging done at designated hospitals, so I wrote a detailed note -basically the timings of his followup CT scan, and asked that the reports should be sent to me. I ordered a CTA prior to discharge which showed a type II endoleak adjacent to the graft and connected to both lumbar and inferior mesenteric arteries (first image above). After some thinking, I took the patient for an aortogram, accessed the IMA via the SMA and coiled into his AAA sac and the IMA.

It was only a few weeks ago one of my colleagues across town contacted me that the patient had been admitted with abdominal pain, a CT showing a type II endoleak from his lumbars, but a smaller AAA sac than his pre-repair size of 8.5cm. The patient is seeking to repatriate, and I doubt he would be able to get adequate followup in his home country without paying in cash. Happy that the patient survived his rupture, I still have persistent regrets at not getting him through an open repair, which I am sure he would have done fine with… Or maybe not.

Je Ne Regret Rien…

Recently I admitted a patient, in his 70’s, with a symptomatic 6.5cm infrarenal AAA with bilateral common iliac artery aneurysms, the right being 25mm, the left over 30mm. Because of the pandemic, he was stuck here, seeking to repatriate. Over ten years before, he had a segment of descending thoracic aorta repaired for a traumatic tear -probably one of the last before the wide adoption of thoracic stent grafts which work great by the way.

Cardiac risk evaluation revealed an ejection fraction of 35% with reversible ischemia on nuclear stress test. CTA of the coronaries revealed triple vessel coronary artery disease corroborated by catheterization. Off-pump CABG was planned which would eliminate the effects of cardiopulmonary bypass.

Preparations were made for EVAR with IBE of the left iliac aneurysm as a contingency, but there was no question that if the patient recovered well from his CABG, he would undergo open repair. This was because bell-bottoming or IBE must have regular coordinated surveillance which was not going to be easy with the patient leaving for another country in the middle of a pandemic. It is difficult to get followup to happen in normal circumstances (see above cases). I expressed my opinion to the patient and family and we agreed to see how the patient responded to off-pump CABG.

He underwent off-pump CABG with three vessels revascularized. He was extubated POD#1 and mobilized. By POD #4, he was on a regular patient floor, being co-managed by hospital medicine who takes care of all of our patients. The patient expressed readiness for the next operation. His kidney function remained normal. He was transfused 2 units of PRBC to bring his hematocrit to 30%. He was taken off Plavix, but kept on aspirin. On POD#6, he was taken back to the operating room for open aortic bypass. This would not have been possible without close coordination of cardiology, cardiac surgery, and vascular surgery. Choosing off-pump CABG was a critical element in being able to proceed with open aortic surgery.

Right branch taken to iliac bifurcation, separate bypasses sent to left internal and external iliac bypasses.

I do several things to decrease the physiologic impact of the operation. First is keeping all the viscera retracted under the skin. This simple move has the effect of decreasing the rate of intestinal paralysis and amount of fluid shifts that occur postop, akin to going retroperitoneal. This decreases the space you potentially have if you use standard clamps, but I use the Cherry Supraceliac clamp (image), DeBakey Sidewinder (transverse), or just a Satinsky clamp oriented transversely. This minimizes the occupation of volume over the anastomosis which always happens with standard aortic cross clamps. The anastomosis is easier without the clamp taking up valuable space.

Cherry Supraceliac Aortic Clamp

The iliacs are always clamped with Wylie Hypogastric clamps, again, with the principle of eliminating clamp overhang. Suturing is done with 4-0 Prolene on SH needles -this is plenty (link). The proximal anastomosis wants to bleed, and sewing to a fully cut ring of aorta ensures good posterior bites but also allows for sliding a band of graft down over the anastomosis (Dan Clair calls this a gusset) which works well at creating a hemostatic proximal anastomosis rapidly-trust me, getting this done well is the key step of the operation. Before closing, I infiltrate the rectus sheath and preperitoneum bilaterally with local anesthesia -lidocaine 1% with epinephrine 1:1 with bupivicaine 0.5%. The skin is closed with absorbable dermal sutures because staples create as many problems as they solve. The patient had cell salvage through the case and no extra units of transfused blood.

The patient was extubated that night and started on clear liquid diet. The next day his lines were removed and he was moved to the floor and started on regular diet when he expressed hunger. On POD#2, he was pacing floor, asking when he could be discharged.

Sternotomy and Laparotomy POD#2, walking the floor

As he was eating, walking, talking, breathing, evacuating bowel and urine, and pain free (well controlled), I saw no reason to keep him beyond POD #3 AAA/#9 CABG. I have kept in touch with him and his family and he is doing well and has given permission for this posting.

Satisfaction

This final case has confirmed several of my beliefs. First, calling something high risk can drive one to make bad choices and in fact endanger patients. This last patient would qualify as high risk on any international criteria, and you would not be wrong in quoting upwards of 30% major morbidity and mortality for cardiac revascularization and AAA repair, but you would also be tying your hands from offering the best solution for this man who fortunately was able to undergo two prodigious operations. He will not require much in the way of followup. Coronary revascularization with arterial conduit and open aortic grafting frees him from the need for close followup and reassures us that his repair is durable.

Second, calling something advanced and minimally invasive gives one cachet in the marketplace but forgoes careful discussion and consideration of what is being abandoned. The first two patients survived their ruptures but now face the consequences of having stent grafts. It is a shame when podium speakers at international symposia declare surgery to represent failure because this affects training by encouraging abandonment of hard to acquire skills. It seeps into patient perceptions and expectations. I hope that a balanced approach prevails. You have to be capable of both open and endovascular approaches to be able to offer the best treatment for a particular patient.

Finally, these old operations are cost efficient and there is a lot of room to improve these procedures with new perspectives, techniques, and data. I don’t operate the same way I trained, and it is only through continued application of operations that improvements can come about. As budgets tighten and economies are stressed, cost efficacy will rein in much of the interest and demand in new stuff unless it adds value. That said, I am grateful to our stent graft representatives who have worked to get us bell bottoms and IBE’s for when they will be needed. These grafts will be used when the time is right.

Categories
AAA Commentary common iliac artery aneurysm EVAR iliac artery aneurysm imaging open aneurysm surgery

When You Pay Your Own Way, You Chose Value

abd angio  11836788149..jpg

The patient is an active man in his 60’s with a history of hypertension who had known about a right common iliac artery aneurysm for several years and had come for an opinion. He was asymptomatic of pain. He had a prior splenic artery aneurysm embolization about a decade prior to presentation.. CT scan showed a large eccentric aneurysm arising from a retrograde chronic dissection dilating the right common iliac artery to over 4cm. This is typically iatrogenic, but impossible to know for sure. The left common iliac artery was ectatic to 2cm as was the aorta to 3 cm and all were “wavy.” This sort of tortuosity is the result of remodeling in the axis of flow resulting in lengthening of the artery and is found in those with the substrate for aneurysmal degeneration (footnote). He did not smoke and he could climb stairs without dyspnea or chest pain.

abd angio  1605093750..jpg

On examination, he was a fit middle aged man with a slight paunch. His abdomen was soft and his peripheral pulses were present and normal. Laboratory results were normal, including creatinine. EKG and echocardiogram were also normal.Treatment options were discussed in detail. The patient was paying for the operation himself and wanted to understand in detail the possible options. These included

1. Open aortobi-iliac bypass with a jump bypass to the right internal iliac artery
2. Open aortobi-iliac bypass with ligation of right internal iliac artery
3. EVAR with right external iliac extension after embolization of right internal iliac artery
4. EVAR with parallel grafts to right external and internal iliac artery (off label)
5. EVAR with iliac branched graft to right internal and external iliac artery (off label)

People are known to react with emotions and to decide typically for near term gain over far term benefits. The offer of an operation involving laparotomy and a possible weeklong hospitalization with all the attendant risks of death, heart attack, stroke, ileus, wound infection, pneumonia, organ failure and so on provides a stark contrast to the appeal of endovascular repair which can be done percutaneously, with local anesthesia, and with a short hospital stay. The lifelong CT scans are in the murky future compared to the present which is sharply in focus. This is why few people save for retirement, why profligate grasshoppers far outnumber industrious ants. In the same vein, the offer of an “advanced minimally invasive” solution plays to several cognitive biases that exists in the mind of not only the patient but the health-care provider. These include this preference for short term gain over long term gain, but also viewing all innovation as being necessarily better than what was available.

After going over the operation in great detail, the patient cut me off when I mentioned the need for lifelong followup CT scanning. Because he lives in several countries, typically, he has to pay for his healthcare out of pocket and he balked at the notion of paying for an annual CT scan. He was also disdainful of the possibility of reintervention (quoted at 10%) and having to pay for it. Also, the stent grafts, which he would have to pay for, end up being as costly as a new luxury sedan based on local pricing.

We chose open surgical repair via a midline laparotomy. An aortobi-iliac bypass was performed from proximal aorta to right internal iliac artery and left common iliac artery bifurcation with a jump bypass from the right graft branch to the right external iliac artery. Technically, this sequence was chosen for ease of access to the internal iliac artery with the external clear of graft. Operative time was 3 hours. He was in the ICU for one night. He went home after 10 days after contracting a UTI. In followup three weeks after discharge, because he had fevers, a CT scan was performed (figure). He was treated for an upper respiratory infection which cleared, and he has been doing well since. We are both happy that he will never need a followup CT scan.

Before and After

The literature supports this stance. The long term followup of the EVAR-1 Trial (Reference 1) is an example. This was the late followup of the prospective randomized study looking at open surgery versus EVAR in 1252 patients. The initial EVAR 1 findings are well known and put into question the long term benefits of EVAR as the initial mortality benefit of EVAR is lost within a few years of treatment. At a mean of 12.7 years of followup, there were more deaths from aortic aneurysm rupture and aneurysm related death in the EVAR group compared OPEN surgery (adjusted HR 5.82, p=.0064), with 13 AAA ruptures. I have mentioned before that the failure of a handful of pacemakers drove the Guidant company to recall over 20,000 of their devices. Plus, the cost of annual CT scans in the treatment group and cost of devices and cost of reintervention have driven the UK’s NICE Guidelines recommending against EVAR in elective AAA repair. The meta-analysis of EVAR-1, DREAM, OVER, and ACE trials comprising 2783 patients is confirmatory, that aneurysm related mortality was significantly higher after the initial mortality benefit of EVAR fades away, and that patients of marginal fitness gain no advantage from EVAR, particularly those with heart or renal disease, and those with PAD had lower mortality in the period of 6 months to 4 years (reference 2).

I post this case, because despite a complications, in this case UTI and URI, the patient did fine. So why is open aortic surgery considered a dying art? Why is there such pushback against the UK NICE Guidelines?During my residency in the 1990’s, in the heyday of open surgery, I observed a lot of mediocre vascular surgeons and a very few great ones. The average vascular surgeon would take 6-8 hours to perform open aortic surgery, and the patient would come out with a typical picture of oliguria, third spacing, SIRS, that would generate a 1-2 week stay that would even be described as the normal and expected course for AAA repair in surgical and critical care textbooks. The best surgeons back in the day did these operations under 3 hours with 100mL blood loss and the patients would spend a day in the ICU (often not needing it), and 3-7 days in the hospital, but they were the exception.A higher percentage of surgeons today can do EVAR well than surgeons 25 years ago could perform competent open aortic surgery. Most surgeons graduating from training rarely see or do open aortic surgery compared to the multitude of interventions. Capable open surgery basically is not available outside of a few centers, and most surgeons admit to not having equipoise to start a new trial with modern devices. Open aortic surgery is a lost art, like growing your own vegetables, dressing your own game, reading cursive script, and dialing a rotary telephone.

It is not for a lack of desire. I have several younger colleagues I have met or interacted with via social media who have an intense interest in gaining open vascular skills. They have organized open skills courses at major European vascular meetings, but I believe that is not enough.The need for exovascular fellowship, the running topic of conversation of older surgeons through the 2000’s, is never as critical as it is now as we see milennia of surgeon-years of experience retiring to golf courses and cottages. The recommendation for preferring open surgery in the younger and fitter patients is sadly out of reach for most patients and surgeons. The same passion in disseminating endovascular knowledge needs to be applied to repair the damage to vascular education by over-relying on and over-prescribing endovascular approaches.

Finally, and sadly, this patient is the exception. When given clear options and outcomes and costs, this patient made a rational decision, choosing value over convenience.

Reference
1. Lancet 2016;388: 2366-2374.
2. BJS 2017;104:166-178

Footnote:

Pearls for finding AAA:
1. Tortuosity of the internal carotid arteries including loops and hairpin turns found in patients particularly smokers implies the present of a AAA until proved otherwise
2. Palpating bounding popliteal or pedal pulses in an older smoker implies the presence of a AAA until proved otherwise. Especially if the medical student can feel these pulses.
3. African-American Females with Diabetes almost never get AAA.
4. Palpate their abdomen

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).

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.

plaque.png
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.

 

Categories
AAA EVAR techniques training

A Troublesome Accessory Renal Artery Complicating a Complicated Patient

Preop Figure

The patient is an 65 year old man with a growing right common iliac artery aneurysm of 3.7cm, a small AAA, and severe COPD (not oxygen dependent, FEV 1.5L) . He had a prior left nephrectomy for cancer as well as a bladder resection and prostatectomy with an ileal conduit (Indiana pouch or neobladder), with complex abdominal wall closure complicated by infection of Marlex in the past, and prior operations for small bowel obstruction. He is morbidly obese. His kidney function was stable with a Cr 1.5dL/mL, calculated GFR or 44mL/min. His nuclear cardiac stress test (pharmacologic) was normal.

A magnified view of the accessory renal artery is shows below with the arrow

mag preop CT

He needed to have his right CIAA treated but the issues were what to do with his accessory renal artery. Vascular surgery is all about making the right decisions with fall back plans. As with most complicated patients, the options are numerous.

  1. Direct transabdominal open repair
  2. Open retroperitoneal repair –Left sided approach.
  3. Open retroperitoneal repair –Right sided approach
  4. Open debranching right accessory renal artery and EVAR
  5. Parallel graft to right accessory renal artery and EVAR
  6. Coil embolization right accessory renal artery, anticipate worst case postop GFR 20ml/min
  7. Medical management

I informally polled my partners and found an absence of consensus except for rejecting #1, 2, and 7. The first two options were not optimal because of his prior operation and because of the location of his disease. The third option had its proponents, but I felt that the kidney and pouch were in jeopardy from dissection in that area. The open debranching had its appeal for others, but for the same reasons that I rejected #3, I rejected #4 –potential harm to the kidney. #5 may be an option, but in my experience, I have seen too many patients referred for failure of parallel grafts to feel secure about offering it.  #6 would be reasonable if the patient could avoid dialysis. With a calculated CGF of 44ml/min, losing half the remaining kidney would barely leave him off dialysis. By appearances though, the smart money was on losing less than 50% but more than 20%. A 30% loss would result in a GFR of 30mL/min or a Cr of 2.1 which made dialysis not likely. In my experience, the kidney does have some collateralization as evidenced by backbleeding of accessory renals with an infrarenal clamp so it may be that he might lose only 10-15%. I discussed all of these options and medical management with the patient who agreed to proceed with option 5 under my recommendation. My plan was to assess the flow from the accessory renal and proceed if it was small, with plan B being a parallel graft, plan C debranching.

nephrogram

In the OR, the right accessory renal artery was selectively catheterized and a nephrogram revealed that it supplied less than 20% of the kidney. The above diagram shows the extent of the total kidney and the area perfused by the accessory renal artery. I proceeded with coil embolization of it and the right hypogastric artery and EVAR of the AAA/R.CIAA.

post CT

In followup, the patient had a Cr of 1.7mg/dL, representing about 15% loss of kidney function. As the case was done percutaneously, he only had 1cm incision in both groins, and was pleased with his result. No endoleak was seen (CT above).

The telling lesson about this case is that at the time of initial consultation, my first instinct was to prepare the patient for open repair via a right retroperitoneal approach with debranching of the right accessory renal artery as a fallback position. Open surgery is my fallback as it was the foundation of my training. But experience has also taught me that patients with multiple comorbidities often struggle to recover from big operations even if one particular problem is not prohibitively severe. Finally, having smart partners to bounce ideas off of is a not only a luxury but a critical asset.

Categories
PAD techniques TEVAR

External iliac remote endarterectomy in lieu of a conduit for TEVAR

IMG_1281

The patient had diffuse atherosclerosis with small luminal area even in areas without calcified plaque. It predicted inaccessibility for the 22 French sheath required to deliver the 32mm C-TAG device to be placed for a symptomatic type B thoracic aortic dissection associated with a small but expanding proximal aneurysm.

IMG_1277

My options included direct aortic puncture, an aortofemoral conduit, or an endoconduit. The aorta was heavily calcified and the bifurcation was narrowed by circumferential plaque down to 6-7mm at its narrowest and the left iliac had a severe narrowing due to this plaque. The common femoral artery was severely diseased with a lumen diameter of 4mm due to heavily calcified plaque.

I have come to favor direct aortic puncture over conduits, but the heavily calcified aorta and the absence of safe areas to clamp made me think about other options. My experience with endoconduits has been limited to revising problems of endoconduits from elsewhere, but others report it as a feasible option.

The problem with a long artery narrowed with irregular plaque and even intimal thickening is that it will readily expand to accommodate a large sheath but removing it involves the frictional resistance of the whole artery and typically the “iliac on a stick” avulsion involves the whole length of external iliac artery, likely because the common iliac is anchored by the aortoiliac plaque, the smaller diameter of the EIA, and the longer more tortuous path offering greater resistance in the EIA compared to the aorto-common iliac segment.

IMG_1272

Remote endarterectomy, a technique involving endarterectomizing an artery through a single arteriotomy, offers the possibility of increasing the lumen of even a mildly diseased artery and reducing the frictional coefficient, assuming the remnant smooth adventitia is less resistant than rough irregular intimal plaque.

IMG_1275

The plan was to expose the right common femoral artery and endarterectomize it and gain wire access from the R. CFA. A wire would be placed on the left iliofemoral system to protect it for later kissing iliac stents. A right EIA remote endarterectomy would be performed, and then the right aorto-common iliac segment would be balloon dilated to 8mm.

IMG_1278

The operation went as planned. The external iliac plaque was removed in a single piece from the EIA origin.

IMG_1279

Arteriography showed the right EIA to be free of intimal disease, and dilators and ultimately the 22F sheath went in easily.

IMG_1276

The TEVAR also went uneventully -the left subclavian which had a prior common carotid to subclavian bypass, was covered and the aneurysm and flap were excluded from the left CCA to the celiac axis.

IMG_1280

The most difficult part of the operation was removing the sheath, as is usually the case with a tight iliac, but the friction point was largely at the common iliac and not the external iliac. No artery could be seen extruding with the sheath at the groin while steady tension was applied to the sheath under fluoro. The aortic bifurcation was repaired with kissing iliac stent. The patient recovered well and her chest pain resolved.

I have done this for EVAR, including reopening occluded external iliac arteries, and even for a 26F access for TAVR, avoiding the need for placement of a conduit in selected patients.

Addendum: in followup, I had the chance to check up on the repair -the EIA remained large and patent.

before after

Categories
AAA Commentary techniques

The Parallel Bar -higher than you’d think

eye tiger big

At last week’s Veith Symposium, there was a straw poll for parallel grafts versus fenestrated stent grafts in emergent setting, and the results were a populist parallelist majority. This is clearly the result of years of inability to access this technology and reflects market forces making the decision over careful science. There are clear examples of this in the past -the adoption of laparoscopic cholecystectomy and appendectomy, done without randomized control trials shows that RCT’s be damned, people and surgeons will get what they want.

eyetiger1

The several presentations on parallel grafts caught my eye. First was the Eye of the Tiger technique which sounds like a kung-fu move. Presented by Dr. David Minion of the University of Kentucky, the gist of it is that the gutters created by parallel grafts can be obviated by reshaping the branch grafts from circles to lenticular shapes (illustration). The sequence of moves is to deploy a balloon expandable stent graft outside of the main graft and deploy it, then deflate the balloon. The aortic graft is then ballooned, crushing the branch graft. With the balloon inflated, the branch graft is then inflated, now taking a lenticular configuration. This, I will put in my tool box.

Bullfrog catheter tracking (top) and inflated for infusion (botton) with needle out.
Bullfrog catheter tracking (top) and inflated for infusion (botton) with needle out.

The other presentation was on the bullfrog catheter, by Dr. Christopher Owen of UCSF. It inflates to press the catheter portion of it in the middle of the length of the balloon against the stent graft wall. A penetrating needle then comes out through the graft material, allowing for infusion of a sealing embolic material. This has not been tried in humans but application in an animal model is ongoing.

The first time I saw Nellix, this is what I thought...
The first time I saw Nellix, this is what I thought…

I have a feeling parallel grafts will be with us for a while. Using these in conjunction with the Nellix graft, juxtarenal aortic aneurysms were treated, which brings me to think that with the inevitable progression of paravisceral segment aneurysm disease, we will be seeing secondary endobags (not a pejorative) for treatment of paravisceral aortic aneurysms with parallel grafts, and we will see something like this on CT scans one day (illustration). Mr. Ian Loftus of St. George’s Vascular Institute reported on 19 patients (11 single, 5 double, 3 triple branch) over 12 months who were unsuitable for OR/EVAR solutions, treated with 100% technical success, one type I endoleak. Dr. Michel Reijnen presented the Arnhem experience with this technique. Their series included 7 patients with juxta (5) or para (2) renal AAA’s (4 single, 2 double). He reported 100% chimney graft patency and no reinterventions in short followup. He presented a case of rupture, but warned that further investigation would be needed before using the endobag for rAAA.

I think that the whole issue points to several truths. Paravisceral and thoracoabdominal aortic aneurysms have always been viewed with trepidation and this generally caused referral of these cases to high volume centers and surgeons during the open era. Experience with EVAR has infused a sense of confidence and with mastery of infrarenal EVAR and basic endovascular interventions, most practitioners feel ready to offer an endovascular solution to the visceral segment AAA’s, but feel locked out either through lack of training or inability to access the devices, particularly not having ready solutions on the shelf. These parallel graft systems offer relative ease of delivery and use readily available components. Even I have resorted to parallel grafts in an emergency with acceptable short term result (patient lived) but with uncertainty with durability.

I think that there will never be a completely satisfactory off the shelf, “every-surgeon” solution because these patients are no less complex when approached with endovascular technique -they just present a different set of equally difficult challenges. As in open repair of these complex aortic aneurysms, endovascular repair of these should aggregate to high volume practices and centers with deep experience.

Categories
AAA EVAR techniques TEVAR

Percutaneous EVAR and TEVAR -how to get there if you aren’t doing it right now.

24F Access pEVAR
22 French Percutaneous Access circa 2008

Percutaneous access for EVAR and TEVAR does several things. First, the procedure becomes shorter by an hour or two, and (don’t discount not having nursing count instruments because the case was percutaneous). Second, the patients experience far less discomfort and it is easier to discharge them the next day when they have a bandaid versus an incision. And this leads to the third thing: not having an incision means it is far less likely that a groin infection will occur, especially in the obese.

There are three things which you must do before undertaking pEVAR. First, you have to become comfortable with using the Perclose S device in 6F-8F access -about 5 to 10 successful closures will do. You should become facile with the deployment of the sutures and closure of the access point. Avoid small arteries or heavily calcified arteries. This leads to the second point -all of your groin access should be ultrasound guided -this has been shown to improve results in pEVAR (Ref 1). I am a firm believer that the source of groin access complications starts with the initial needle stick. The 18g needle is basically a short 11 blade rolled up into a cylinder, and during groin access without ultrasound imaging, one can shear branch arteries, skewer arteries, dissect plaque, and access too proximally or distally, or into the profunda femoris.

needle is scalpel

The third need is access to 3D reconstruction software and multislice CTA. This gives you powerful ability to predict which patients are more suitable for a percutaneous approach, and which should have a cut down, and with 3D virtual reality reconstructions, you can plan where the incisions will be. In the skinny patient, this is not a pressing issue, but in the merely obese and the frankly obese, and the super obese, choosing to go percutaneous and avoiding a groin complication, which may be the one thing that debilitates the patient far more than a stent graft deployment, becomes an easy decision with experience.

As you build your 6-8F Perclose experience, you may notice that having too tight and subcutaneous tract can result in the suture catching on SQ fat, and not closing, or that bleeding won’t surface properly and create a hematoma under Scarpa’s fascia, often after the patient gets to the recovery room. Expanding on this principle, as you leap to 12F access and preclosure, I recommend you try this -make a 10mm incision, and using a tonsil clamp, pop through Scarpa’s fascia and seat the tips of the clamp under ultrasound on top of the soft part of the CFA that you intend to access. Gently spreading creates the space that you need to deploy the sutures and ensure that any bleeding will exit the skin and not dive under the fascia. It amounts to an ultrasound guided dissection of the common femoral artery. Before you remove the tonsil, you gently maneuver a micropuncture (always) access needle between the tines of the tonsil clamp until it gets to the artery -this keeps the eventual wire going through the tunnel you just made.

12F can usually close with a single Perclose, but start practicing by placing two Perclose sutures in a 10 oclock and 2 oclock orientation. Once the sutures are in, I make sure the  two ends of the suture are pulled out and the end loop of the suture is on the artery and I clamp these sutures to the drapes medially and laterally depending on how I deploy the two sutures. This also helps avoid catching the suture and driving it into the aorta.

After performing EVAR or TEVAR, I remove the sheath, leaving a wire -typically the stiff wire originally supporting the sheath and deploy one of the sutures. This first suture should cinch down onto the artery and substantially decrease the bleeding coming from the access site. I then deploy the second suture, and if the bleeding has stopped or is a steady dribble, I remove the wire. If pulsatile bleeding persists, I recinch the sutures using the knot pushers. If this decreases flow, I remove the wire, otherwise, I place a dilator, stop the bleeding and cut down. Cutting down after SQ dissection means merely dividing skin and tissues over the dilator, and the artery is easily visible for suture placement. If I remove the wire and there is still some bleeding, and usually there is, I place Gel-Foam soaked in diluted thrombin into the tract, reverse heparin, and hold pressure for 10-20minutes. It is very rare to have to convert after this is done.

thrombin gelfoam
thrombin-gelfoam into tract

The skin is closed with an absorbable 4-0 monofilament suture, and skin glue. I usually use the micropuncture needle to give an ilioinguinal field block with Marcaine. This gives 24hrs of pain relief.

bandaids

A note about incisions. Usually, with 3D VR imaging of CTA, the CFA and its quality (size and absence of plaque), and location relative to the inguinal crease can be ascertained. I try to make the access point at the inguinal crease or distally, as this goes under the subpannus of groin fat rather than through it.

groinaccess
3D-VR imaging can pinpoint optimal access

I sincerely believe sheath size is not the limiting factor to percutaneous access. Rather, it is the common femoral and iliac artery. Zakko et al at the University of Florida just published their experience on the obese with percutaneous TEVAR (ref 2), and found that while the arteries were deeper, the technical success rate of staying percutaneous (over 90%) was no different between their obese patients non-obese patients. The predictors of failure were poor access artery quality and size. I believe that you can select for patients most likely to succeed and greatly reduce failure. In this population, groin complications are potentially life threatening, and avoiding an open groin exposure is valuable.

 

References

1. J Vasc Surg 2012;55:1554-61 (ultrasound guided access)

2. J Vasc Surg 2014;60:921-928 (p-TEVAR and obesity)