Tag: #vascsurg

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Commentary

Is there a doctor in the house?

Choose to Be a Hero

There was an OpMed article on Doximity (https://www.doximity.com/newsfeed/1946e8dd-eddc-4eb4-aad6-46fe59c86da5/public) which reports that 69% of 58,000 physicians surveyed said they would provide emergency care. That number is depressingly low at first view but can be answered by asking how many of us are ATLS, ACLS, or BLS certified? A quick search fails to give a result, although various pro CPR groups have on their websites that all caregivers should be trained in BLS. The darker question is how often do fully trained and certified physicians choose to withhold care and hide their identities?

I can give you a quick answer. Most doctors will sit on their hands when the PA announces “is there a doctor on the plane?” hoping that someone else will raise their hand. Back when I was a second year surgical resident, I took a vacation with my wife to London and Paris. On the flight, over the Atlantic, the cabin crew asked for any medical assistance. Before I had a chance to contemplate the question my wife jumped up and pointed at me and shouted “He’s a Doctor!”

I was in shorts and hoodie, with a baseball cap. Back then in my late twenties, I looked about 15 years old. The British Airways stewardess looked at me dubiously, then looked around behind me to see if any other hands were raised. <sound of crickets>

She escorted me up the stairs to first class and in one of the giant chair-and-a-half recliners was a pale fellow in a nice suit, diaphoretic, dyspneic, and maybe a little drunk. He couldn’t speak well but was awake and maintaining his airway. His radial pulse was thready and weak. I pressed the button that fully reclined him into a bed, not a little jealous.

“Are you having chest pain?” <head shake>

“Do you have pain anywhere?” <head shake>

“Are you diabetic?” <¯\_(ツ)_/¯>

Cold, clammy, dehydrated, drunk -hypoglycemia was my diagnosis. I asked the stewardess if they had any tubing, a funnel, and orange juice -because that is how you deliver sugar to someone who can’t protect their airway. I was an enthusiastic PGY2 and the orange juice enema was one I was eager to roll out. She looked at me funny and handed me a large black leather suitcase -the kind you see sniper rifles disassembled and packed. In it was a pretty thorough crash cart with defibrillator, airways, Mac blades and handles, bag mask, IV’s, bags of saline, and boxed syringes of code meds including D50. Oxygen was available. It was British Airways first class after all.

I looked around and saw no great place to hang an IV, so I grabbed the D50, horse needle and all, and found his cephalic vein and injected the whole vial. The change was instantaneous -the eyes which were spinning beachballs, stopped wobbling and focused. All that was missing was that Apple Macintosh “bongggg” sound. I gave the fellow a gauze and instructed the stewardess to give him orange juice spiked with sugar.

“Shall we land?” asked the stewardess. The neighboring passengers, all dressed as if for a fancy cocktail party, looked at me with eyes that said, “We really need to get to London.”

“Where are we?” I asked.

“Over Reykjavik. The captain needs to know now.”

I look at my patient, and he had unreclined himself in his fancy leather loveseat, and shook his head. “Thanks. I’ve got to get to London for a meeting.” He was going to be fine. I recommended he see someone for his diabetes (which he confessed to neglecting), and I walked downstairs and back to my seat in steerage.

A older couple (I’m sure they were middle-aged like I am now) was next to us and the lady smiled, and the man leaned over and asked, “how did it go?”

“Hypoglycemia. Are you a doctor?” I says.

“Why yes, a cardiologist. We’re going to London for a conference!” he chirped. I think he caught that I was giving him an accusing look, and added, “you’re wife volunteered you so well, so enthusiastically, I figured you had it well in hand. Good job.”

I sat down and my wife immediately asked, “did you ask them to upgrade us?”

“No.” That is the advantage of a wife when she isn’t volunteering you for missions, she’s looking out for your interests. I was going to make some grand statement of my purpose in life, but was interrupted. The stewardess came up with a brown bag full of tiny bottles of liquors, spirits, and whiskeys, which made me very happy, but my wife just rolled her eyes.

“You would have been happy with a cookie,” she hissed. “Why didn’t you ask for an upgrade? What’s wrong with these people?” And I thought the same, for a different reason. Seated all around me were likely cardiologists headed to London for that conference. Just counting bald heads, there were at least twenty.

Now, nearly thirty years on, I don’t blame those fine folk for not being quick on the draw. I am sure one of them would have stood up eventually, but the last thing you want to do on vacation is work, and what I did upstairs in first class was not much different from the work I was doing every other night on call (this was 1995).

Now, in the middle of my career, there isn’t much that gets my blood running, so I empathize with the festive, sanguine attitudes of the many physicians probably on the plane with me, headed for a nice holiday and conference in London. Some happy fellow jumps up and takes care of the problem, so no need.

Also, I’m not shy in crowds or stressful situations. Everyone in first class was watching me get venipuncture with the D50 syringe and the horse needle which was easy because the fellow was so thin. At that point in my life, screaming HIV positive crack addicts fighting you while getting central lines and spinal taps were the norm. I suppose I couldn’t fault someone more bookish and scholarly for not standing up right away. I assume 69% would have.

I’ve been called about a half dozen other times on planes. It used to be my wife volunteering me, but over the years, even she has taken on a bit of a glazed attitude. The last one a few years ago was a poor fellow whose wedding ring was causing an ischemic finger, made worse by traumatic attempts at removing the ring. Soap and rubber bands fixed him. It barely elicited an eye roll from the spouse who did not volunteer me that time. It was one of those cheap airlines in the American Southwest and I got nary a thanks.

I have never contemplated the medical malpractice ramifications of rescuing someone, saving a life. I assume something like sea-law prevails up in the air, where the captain can marry folks and push them off gang planks, where decency, need, and common sense prevails over tort law. Unfortunately, I have never seen another black suitcase since that first time on British Airways, and the pre-9/11 days of carrying a pocket knife are long gone, making emergency surgeries and fashioning of MacGyvered medical devices impossible. The idea of embarking on supporting the life of someone when the last time you ran a code was in medical school may be too much to ask someone, and doing the wrong thing may be worse than doing the right thing badly.

Did you know you can fix a tension pneumothorax with a pen, a rubber band, and a condom, with the appropriate knife and fortitude, and maybe a tiny bottle of vodka.

But isn’t that why we went into medicine? To save a life is to save the world, the Talmud tells us, and we can be heroes, if just for one day.

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AIOD aortoiliac endarterectomy aortoiliac occlusive disease (AIOD) PAD stent removal techniques

Removing failed aortoiliac stents: an aortoiliac endarterectomy to engineer a lasting hemodynamic solution

The patient is a woman in her forties who works hard and smokes cigarettes to find stress relief. The year prior to presentation, she began to get cramps in her calves while she walked the halls of the building she cleaned, and this became unbearable. A consultation at our hospital revealed moderate to severe diffuse atherosclerosis without a dominant lesion but notable small distal aorta and iliac arteries with a 50% stenosis of the left iliac origin. Recommendations were to quit smoking and exercise. She found this difficult to achieve and went to another hospital nearby.

There, 6 months prior to presentation, she began complaining of painful cyanosis of her toes which was described as blue toe syndrome. These outside studies were not available. She was taken to the OR and her common iliac arteries were stented. This gave her relief, but the soon pain returned three months later -her stents had occluded. This was treated with more stents, extending them proximally into the aorta and distally in the case of the right across the iliac bifurcation. This afforded her relief for three more months until one weekend she found herself unable to walk again for more than minimal distances, and she took herself to my hospital, University Hospital, Cleveland Medical Center.

On examination, she was a large woman with no femoral pulses, but signals could be obtained in her popliteal and tibial arteries. Her PVR’s showed inflow disease and poor flow at the feet.

Her baseline CTA in workup of her claudication the year prior to getting stented shows the aorta and iliacs, while open, are small, with aortic lumen diameter reaching 10mm and common iliac lumen diameter at 6mm with diffuse atherosclerosis (below).

Aorta scanned winter prior to index intervention showing small aorta diameter of 10mm and diffuse narrowing of common iliac artery, 50% stenosis left CIA orgiin. Intervention was not scheduled. Patient went elsewhere and underwent intervention .

The CTA on presentation shows bilateral stent occlusion. A closer look shows the second set of stents extending the original stents both proximally into the aorta (raising the bifurcation) and distally into the external iliac and across the internal iliac origins (white arrows). The internal iliac arteries, despite the stents and on the right thrombus in the stent, supply flow to the external iliac arteries which have not thrombosed.

The treatment options were

  1. Exercise and risk factor modification
  2. Reintervention
  3. Axillo-bifemoral bypass
  4. Aortobifemoral bypass
  5. Aortoiliac endarterectomy and patch angioplasty, stent removal

Although exercise and risk factor modification should be part of the treatment regimen, the best time to institute this was before her first intervention. With the long segment occlusion of her stents, coverage of the right internal iliac artery and occlusion, and acuity of her symptoms, this is no longer feasible.

It reveals a certain kind of bias when we prescribe walking exercise to those who can’t afford gyms or equipment, and whose neighborhoods are unwalkable.

Reintervention, having failed once, will not be durable. Even with anticoagulation, any recanalization -thrombolysis, thrombectomy, balloon angioplasty, atherectomy, lasering, and restenting, would not be durable.

It is likely the patient is frequently vasoconstricted and this is exacerbated by smoking. While never diagnosed with Raynaud’s, she did give a history of easily have numb, cold fingers and toes in the chilly winters in Cleveland. Even normal spectral Doppler signals will show pauses in flow in the peripheral arteries. Combined with any hypercoagulability and injured lumenal surfaces from interventions, and stents will go down.

An Aside on Small Aorta Syndrome in Women

One of the advantages of being a village elder is you remember forgotten concepts that guided treatment “back in the day.” The small aorta syndrome defined as having an aorta smaller than 12mm in diameter is one of those. Best described as not having enough pipe -imagine a small caliber fuel line throttling an engine. For all the muscles involved in standing and walking, there is a minimal diameter necessary for function.

Small aorta syndrome stands up to objective testing. A patient with a small aorta but otherwise patent lower extremity arteries, can present with claudication and demonstrate drops in ABI with exercise. These are typically female smokers with elevated BMI. Along with their small aortas, their external iliac arteries will be small, and I used to wonder if some critical period of inactivity in their early years failed to grow these arteries, or if this process of normal growth and remodeling is retarded by smoking.

Small aorta was a common indication for aortobifemoral bypass (ref). Unlike some abandoned indications for operation like “4.5cm AAA” and “asymptomatic 60% internal carotid artery stenois,” it had a testable finding of drop in ABI with exercise, but its acceptance has waned in the advent of the endovascular era. In a purely open era, I think there was greater emphasis and awareness on engineering the hemodynamics. While endovascular interventions simplify treatment, just stenting a small arteries usually doesn’t fix the problem as illustrated in this case. That is because there is a maximum size that the arteries receiving the stents will allow.

The iliac artery and aortic bifurcation will only tolerate so much upsizing with stents before rupturing. The interventions are constrained by the size of the adventitia. What is also ignored is the concept of elasticity -the 7mm lumen through a reopened and restented artery provides more resistance to flow than a 7mm artery restored via endarterectomy. All stents decrease elasticity of the circuit and decreases flow in a pulsatile circuit because of the increased impedance. Bovine pericardial patches on the other hand add elasticity. Endarterectomy restores elasticity. .

Enough Pipe

In the early 2000’s, I used to live in an pre-war apartment in Riverdale down the hill from Drs. Takao Ohki and Frank Veith. The apartments above and below me all shared this same feature -poor water pressure, because during a restoration twenty years before, the owner used the wrong, smaller size of pipe for this line of apartments. The taps would run, but if more than one apartment ran the shower or dishwasher, the taps would drip. The apartments would claudicate. The pipes were all patent, but inadequate. Not enough pipe. This patient endowed with small vessels, grew a large body, and smoked, and her muscles needed more pipe to support the added load. Not enough pipe.

So is the solution an aortobifemoral bypass? It is the board answer and a durable one, but it shares with axillobifemoral bypasses the risk of groin infections, particularly with a large body habits (below). The outflow arteries, all patent, are small and likely subject to vasoconstriction. My choice of ABF graft in this patient is a 14x7mm bifurcate which is on the small side, but I would be afraid that a 16x8mm graft would be too large on both the aortic and iliac side, resulting in mural thrombus formation.

A vertical groin incision will create a 3 inch deep canyon in the fat to get to the CFA

Axillo femoral bypasses, aside from the groin issues, suffer from poor long term durability and is not a great choice for a 40 year old. Her axillary artery was 6mm and sourcing flow to the lower torso from that is never great. Also, supplying a long 8 or 10mm graft would recapitulate the original problem of a small aorta. Not enough pipe.

For me, the best option would be to remove the stents and restore the distal aorta and iliac arteries to their original elasticity and slightly larger than original diameter. I would then be able to reopen flow to the occluded right internal iliac artery. Not just enough lumen, but enough and correct pipe.

Technique: Exposure

Exposure is predicated on the planned extent of the endarterectomy, place for clamping, and plans for aortobifemoral bypass if the endarterectomy results in poor adventitia. In a woman, the iliac bifurcations are easier to reach. A midline laparotomy is the incision of choice here. Let me digress here about the laparotomy. Over the three decades since the launch of laparoscopic surgery and subsequently endovascular surgery, the midline laparotomy has gotten an undeserved bad rap. Laparotomies are well tolerated and should not be viewed as a rare bailout or outright failure of laparoscopic therapy. Rather, it is still the gold standard exposure.

The infrarenal aorta to the right external iliac artery is exposed as well as the common iliac. In this patient the sigmoid mesentery was fatty and did not readily expose the iliac bifurcation so a separate exposure of the distal left common iliac artery was performed by mobilizing the left colon.

The aorta above the bifurcation was prepared for clamping. This involves circumferential exposure as I prefer a transverse aortic cross clamp. The lumbar arteries are clamped with bulldogs or aneurysm clips. The right external iliac well beyond the stent is controlled and the internal iliac is exposed and controlled. On the left the internal and external iliac arteries are expose and controlled.

The patient is heparinized clamps applied, and I make the arteriotomy with a 15 blade cutting down to the stent. The aorta is cut to a point about a centimeter below the clamp. The external iliac is cut to where there is patency of the artery and the plaque is mild. The endarterectomy is performed in the same way one does a carotid or femoral, with care to find the correct endarterectomy plane outside the plaque and good end points where the plaque adheres well. The internal iliac plaque on the right was chronically occluded but was successfully removed via eversion resulting in back bleeding. I sound the artery with a dilator to make sure a dissected plaque isn’t occluding it then reclamp.

The left common iliac artery is opened via a separate arteriotomy as I find tailoring a Y-shaped patch laborious. The arteriotomy is extended under the sigmoid mesentery and then moving the left colon medially the arteriotomy is finished slightly beyond the external iliac origin. The endarterectomy is finished short of the iliac bifurcation and any narrowing at the bifurcation is treated with the patch.

The specimen shows that the adventitia remains separated from the stents by the plaque. I rarely use tacking sutures as I feel a properly performed endarterectomy results in no plaque or well adherent mild plaque.

The patch needs to be thoughtfully applied. An overly large one will billow, and at worse case, create an artificial aneurysm. For example, for a 7mm iliac artery, the circumference is 22mm. Adding an 8mm patch with 1mm suture bites results in a 26mm circumference and an 8.3mm end diameter. Narrower is okay, but much larger will result in size mismatch that the body compensates for by laying mural thrombus. A long 8mm wide patch can be cut from a large swatch of bovine pericardium, remembering to add a slight angulation onto the iliac artery.

This operation avoids the groins with exposure or access into a small artery with a large sheath. A 4mm artery with 12.6mm circumference receiving an 8F sheath receives a 2.6mm hole, a 40% defect across the anterior hemicircumference of 6.3mm. This is not trivial, particularly because the arteries are often atretic after prolonged occlusion, may tear with a closure device, most of which are off IFU for such a small vessel. Avoiding the groins altogether is a great benefit to this type of procedure.

A postoperative CTA showed wide patency of the restored aorta and iliac arteries.

At followup several months after the procedure, the patient was walking well without claudicating and was ready to return to work. PVRs showed excellent flows down to the toes.

Hemodynamic Engineering

A surgical trainee has to develop a sense for flow. Looking at a circuit, she has to ask “how does blood get from point A to point B?” Merely providing a pipe does not mean a cure. For example, replacing a blocked artery with a steel pipe would provide flow but it has a hemodynamic impact that is different from the native vessel. Flow stoppages during the cardiac cycle that is modulated in a normal artery by the elasticity of its wall. While we don’t deliver steel pipes, we do something similar in ballooning heavily calcified arteries, or stenting them. ABF with prosthetic bypass offers a safe, broadly available method of treating this, but is fraught with problems for patient who develop groin infections or occlude a bypass for the reasons previously mentioned. Endarterectomy and patching with bovine pericardium allows for more precise restoration which would be a laudable goal in a young patient.

And my final point is this. This patient can yet undergo aortobifemoral bypass. Ironically, even larger stents may be safely placed than was previously possible. One of the principles laid out by Dr. Jack Wylie in his peerless surgical atlases was of leaving a patient in a condition to allow for future necessary operations. For a forty year old patient with many decades left, this is a critical concept.

This case represents the second aortoiliac endarterectomy I performed to remove failed stents. The third just happened today with resection of failed CERAB stents which I did with my chair and fellow Mayo Alum, Dr. Jae Cho. I think that there is a room for this operation which should not remain in the history books.

For a video presentation from Dr. Pat O’Hara: https://vascsurg.me/2022/10/15/aortoiliac-endarterectomy-removing-occluded-stents-is-possible/

References

Cronenwett, JL, Davis JT, et al. Aortoiliac occlusive disease in women. Surgery 1980; 88:775-84.

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Commentary

The Crab Trap

At the VEITH Symposium, which I attended briefly last week, while I foraged for lunch and sought out friends, I wandered into a crab trap (diagram above). Or more specifically, the WL Gore exhibit hall (below).

The coffee and bevarages featured all day, and the steak buffet at lunch, draws people in, like the smell of chicken to a crab, and once you have a plate of food, you then are kind of committed to moving forward into the conference room where they have a video feed of aortic symposium and tables to gobble your lunch.

Like a hand reaching into a crab trap to retrieve the catch, the reps wander in and chat you up, but thankfully only if they know you, which is fine because any hard sales tactic would trigger a fight or flight reflex that would ruin the generally chill atmosphere. There are exits to the left because, you know, fire codes, but they are small, and going out the way you came in risked bumping people juggling plates of their lunch, cups of their coffee. So you go in, sit down, and nibble, watch someone you vaguely know up on the big screen who just decided to go full head shave bald (why is that a thing?), check your phone and find out your friends are in another trap on the other side of the center. And their doors are closed, invitation only. Silly crabs.

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MALS May Thurner's Syndrome median arcuate ligament syndrome Nutcracker Syndrome SMAS superior mesenteric artery syndrome techniques

Arterial Median Arcuate Ligament Syndrome (aMALS)

Median arcuate ligament syndrom (MALS), also known as celiac axis compression syndrome (CACS) and its eponym Dunbar Syndrome, is manifest as epigastric abdominal pain and a compendium of symptoms, arising from chronic compression and inflammation resulting from compression of the celiac plexus between the median arcuate ligament and the celiac axis.

Graphic showing the pathoanatomy of neurogenic MALS (from ref 1). The repeated trauma to the celiac plexus results in inflammation and nerve injury with transmission of pain and neuropathic sensations.

The diaphragm muscle descends from the neck during development (the phrenic nerve originates from C3-C5 nerve roots), and in perhaps up to 25 percent of individuals, drapes across the origin of the celiac axis, and sometimes anchors further down impinging on the SMA or renal artery origins.

While a significant number of patients have this coverage of the celiac axis origin, not everyone has pain. Some whose celiac axis is compressed develop post-stenotic dilatation. For some of these, there is damage to the celiac axis resulting in intimal injury, dissections, thromboses, webs. Turbulent flow causing post-stenotic dilatation in the celiac axis can proceed to aneurysm formation. Downstream in the splenic and hepatic artery and its branches, turbulent flow can engender tortuosity (lengthening) and aneurysms (widening). This disease subset of celiac axis compression should be termed aMALS (arterial median arcuate ligament syndrome).

A question was asked at this year’s VEITH Symposium as to whether post-stenotic dilatation due to median arcuate ligament compression could be considered an aneurysm. The answer given was no, but I think it would be yes in the above example.

Both arterial and neurogenic manifestations of celiac axis compression are under the same ICD code of I77.4, referring to both celiac axis compression syndrome and median arcuate ligament syndrome. While I would never suggest more ICD codes, there should be a differentiation similar to the other compression syndrome, thoracic outlet syndrome (TOS). The pain-based syndrome, which is more common, should be termed neurogenic MALS, or nMALS, and the arterial disease secondary to celiac axis compression should be termed arterial MALS or aMALS. The treatment of nMALS is surgical ablation of the celiac plexus along with median arcuate ligament release, done via open, laparoscopic, and robotic techniques. The treatment of aMALS is the treatment of the arterial complications of celiac axis compression and should involve median arcuate release and treatment of the arterial pathology with either open or endovascular techniques.

Case Presentation

The patient is a middle-aged man with several months of right sided abdominal pain, mostly in the right midaxillary line at the costal margin, right upper quadrant abdominal pain, and right sub-scapular pain. He did not have gallstones, and had no gastrointestinal complaints. He is hypertensive and was on a single agent which he took in the mornings. His pain began during the day and crescendoed in the evening. His prior visits to the emergency room had revealed a hepatic artery aneurysm and celiac axis aneurysm. In the ED, his examination was significant for pain and mild tenderness in the right upper quadrant of his abdomen. He underwent a CT scan.

Common Hepatic Artery Aneurysm, 2.4cm with celiac axis ectasia to 14mm, median arcuate ligament compression of celiac axis

The CTA showed compression of the first centimeter of the celiac axis by the median arcuate ligament of the diaphragm and mild post-stenotic dilatation to 14mm. At the terminus of the common hepatic artery, where the hepatic bifurcated was a 2.4cm aneurysm with mural thrombus. With blood pressure control, his pain remitted.

The trainees and I had a lively discussion as to indications for repair and whether this constituted a symptomatic aneurysm. As I have stated in past posts, all pain has a nerve and a mechanism for pain. Abdominal pain and its points of referral are well known going back to the 19th century and encapsulated in Cope’s Early Diagnosis of the Acute Abdomen, whose most recent steward, Dr. William Silen just passed this September. Processes involving the gallbladder and nearby hepatic artery refer to the right upper quadrant abdomen, right chest, right shoulder and scapula which was where the patient’s pain was. And it improved with controlling his hypertension. There was no question to me the aneurysm was symptomatic, likely from strain on the aneurysm.

The question then devolves to whether this is to be done endovascularly or open. While it seems straightforward for me, I have realized at large meetings there will always be some endovascularist proposing something. For me, to exclude pressure from the aneurysm and avoid rupture, the aneurysm had to be isolated from the blood flow and pressure. Ideally, this would be done with tiny covered stents.
There are no 7mm x 4mm stents bifurcation stents.

Hypothetical bifurcated small stent system -does not exist, would not work.

Embolization of the hepatic aneurysm, which is done for the splenic, offers hazard of hepatic ischemia. Despite what is written in the textbooks about the portal venous system providing most of the perfusion of the liver, you have to remember there is only portal flow when there is food. Acutely losing one of the hepatics, even clamping it for a time, reverberates as a spike in the LFTs, along with attendant systemic inflammatory response. While the liver, like spleen, can recover and regrow, you mess with it at your great peril. Based on the CTA, closing the hepatic artery with coils and plugs will likely be tolerated as hepatic flow would continue via the gastroduodenal artery which is not small, but there is no guarantee that the aneurysm wouldn’t be pressurized yet by the prominent GDA (if you disagree please feel free to comment).

He was prepared for surgery with echocardiography (normal) and lab testing (normal LFT’s, CBC, BMP, INR), and taken to the OR. A chevron incision was made to broadly expose the area. The median arcuate ligament was exposed and released -there was dense tissues proximal to the dilated celiac axis. The aneurysm was dissected out and the small branches were carefully dissected out and controlled. It is easy to injure the branch hepatic arteries which can constrict on dissection.

A suitable length of saphenous vein was harvested and prepared. The three vessels diagrammed above did not present themselves suitable for a single Carrel patch so I sewed end to end to a patch incorporating the right hepatic and gastroduodenal arteries, and performed a sequential side to end anastomosis to the left gastric artery.

The patient recovered well and was discharged home on POD#5, and in followup had no further symptoms.

Discussion:

The differentiation of arterial and neurogenic manifestations of MALS is an important refinement of our understanding of this disease, which I believe to be a byproduct of our bipedal lifestyle. The lordotic curvature of the spine, necessary to balance our upper torso on a vertical spine, pushes the spine forward and applies tension to the median arcuate ligament, along with other structures such as the duodenum and left renal vein in superior mesenteric artery syndrome and nutcracker syndrome, and the left iliac vein in May-Thurner Syndrome.

This compression is not only enough to narrow the celiac, but injure the artery by crushing. Stenting here does not do well because of the external compression and even after release, the artery may be damaged and require repair.

The chevron exposure heals well and is well tolerated and offers perfect exposure. While I was doing it, it occurred to me that a laparoscopic bypass is technically possible, and may be preferred to the long incision. Recent multi-institution study of MALS treatment would suggest laparoscopic approach offers a lower complication rate compared to open surgery (ref 2.)

The critical thing is having more surgeons recognize the compression that occurs in the abdomen and manifests in disparate and unconventional ways. The key is tying pain to a lesion, a mechanism, a nerve, just the way Cope’s does.

References

  1. Weber JM, Boules M, Fong K, Abraham B, Bena J, El-Hayek K, Kroh M, Park WM. Median Arcuate Ligament Syndrome Is Not a Vascular Disease. Ann Vasc Surg. 2016 Jan;30:22-7. doi: 10.1016/j.avsg.2015.07.013. Epub 2015 Sep 10. PMID: 26365109.
  2. DeCarlo C, Woo K, van Petersen AS, Geelkerken R, Chen AJ, Yeh SL, Kim GY, Henke PK, Tracci MC, Schneck MB, Grotemeyer D, Meyer B, DeMartino RR, Wilkins PB, Iranmanesh S, Rastogi V, Aulivola B, Korepta LM, Shutze WP, Jett KG, Sorber R, Abularrage CJ, Long GW, Bove PG, Davies MG, Miserlis D, Shih M, Yi J, Gupta R, Loa J, Robinson DA, Gombert A, Doukas P, de Caridi G, Benedetto F, Wittgen CM, Smeds MR, Sumpio BE, Harris S, Szeberin Z, Pomozi E, Stilo F, Montelione N, Mouawad NJ, Lawrence P, Dua A. Factors Associated With Successful Median Arcuate Ligament Release in an International, Multi-Institutional Cohort. J Vasc Surg. 2022 Oct 25:S0741-5214(22)02443-0. doi: 10.1016/j.jvs.2022.10.022. Epub ahead of print. PMID: 36306935.
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Commentary

Top 5 FAFO’s in Vascular Surgery

5 Top FAFO’s In Vascular Surgery

In no particular order, I list these problematic situations that are outsized in their ability to take a case sideways.

  1. Ischemia syndromes in the unconscious. The unconscious tell you nothing about their pain and follow no commands. Therefore, vigilance and a low threshold for operating are what will save the patient if they are salvageable. Objective evidence of flow -examination, handheld pulse Doppler, duplex ultrasound, CT angiogram, exploration and visual inspection, must be obtained. The typical scenarios are dissections of the ascending thoracic aorta, polytrauma patients, and patients on ECMO. By the time the dissection is repaired and the patient is off pump, they may be long past the 6 hour threshold for irreversible ischemia for gut or muscles. The patient involved in a rollover MVA who had their femur fracture reduced after ten hours waiting on the add on schedule should have their compartments assessed visually through fasciotomies. Patients on ECMO via femoral access must by practice have distal perfusion cannulation. Assessment for ischemia need to start at admission for the unconscious patient with assessments of flow and function. Waiting until markers of cell death are apparent on blood tests is not the right approach unless the patient is DNR.
  2. Operations in redo or irradiated fields. Preparation and coordination is key. Most vascular surgeons have a plan for controlling arteries and veins in these settings, but a common scenario is in trauma or oncologic surgery. I don’t know if anyone has done this, but the idea comes to me that if there is concern for oncologic invasion of a major artery -an aorta or iliac, it would be reasonable to place a wire, balloon, or stent graft across that area with solid seal zones to allow for free dissection and resection of any involved artery.
  3. Central venous rupture during venoplasty for hemodialysis access with an open fistula. Instead of venous pressures, with a fistula attached, arterial pressure is driving the leak. A leak of an SVC can lead to a fatal cardiac tamponade. Because the heart fails to fill, CPR is futile. The only thing can be done once this has occurred is to be prepared to a. ligate the fistula, b. Drain the pericardium either with needle pericardiocentesis or left anterior thoracotomy. Better still is preparing for SVC venoplasty by balloon occluding the fistula prior to inflating the balloon in the SVC.
  4. Rapidly progressing skin infections. It is amazing how fast necrotizing infections can progress. I’ve seen simple infections of a finger spread to the whole arm over the course of an hour or two in the waiting room of an emergency room. There are forgotten anecdotes of medical students dying after nicking their hands in gross anatomy. I saw a concert pianist lose her arm after getting a thorn from her rose garden. The image below is of a forequarter amputation I had to perform on a young man with a fulminant infection of the muscles of the left upper extremity undergoing a forequarter amputation after an overnight of misdiagnosis as a cellulitis at an outside facility. It grew among other things Candida auris, a terribly frightening organism and spread to his chest wall and ribs, resulting in death.

5. Iliocaval venous injury, particularly small tributaries going under aorta or around its branches. While not pressurized, they have tremendous flow like a hole in a plastic bag holding a goldfish, and without precise control, you are as likely to widen the hole or make more holes as you try to suture the holes. I’ve had some success using the Park clamp (link). You can’t buy one but you are free to have one made by your local smith. Otherwise, you need to keep your finger on the hole while you call in help, usually in the form of more vascular surgeons to get exposure and the vein properly clamped for repair.

Add yours in the comments below.

Categories
AIOD aortoiliac occlusive disease (AIOD) techniques

Aortoiliac Endarterectomy: Removing Occluded Stents Is Possible

I recently had lunch with Dr. PJ O’Hara, emeritus professor, and former partner of mine from the Cleveland Clinic. We hadn’t met since 2018 at the VAM in Boston, while I was still in Abu Dhabi. It was a recent case I did that caused me to reach out. I won’t be posting that recent case in detail today -it was a patient who had had multiple aortoiliac interventions for aortic bifurcation disease, but who closed up their stents within a few months of intervention. Rather than subject that patient to another round of interventions, I chose aortoiliac endarterectomy because the prior interventions failed to address the basic problem of the undersized aorta and iliac arteries.

The last case that Dr. O’Hara did before retiring was an aortoiliac endarterectomy which I assisted with, nearly a decade ago. During that case, Dr. O’Hara mentioned a video he had put together for an SVS meeting. He was kind enough to give me a copy share.

Aortoiliac endarterectomy -forget thee not!

The modern application of this technique is in the removal of occluded aortoiliac stents. The aorta and iliac arteries are restored, and yes, stents can go back in if needed.

A quick survey of some of my contacts at major centers reveals that this technique is rapidly becoming forgotten as its practitioner retire or revert to teaching the technically easier aortobifemoral bypass (ABF) graft. I hope to revive this because I know there are many patients who have challenging anatomy for ABF but potentially could undergo plaque and stent removal and restoration of their aorta and iliac arteries.

Categories
Carotid techniques

Brain Claudication -is it a thing?

CTA tends to overread stenoses which was in the 60-79% range on duplex

The patient is a middle aged executive who complains of bouts of aphasia triggered by intense conversations and business meetings. It first occurred while driving to Dubai on a conference call. Since then, they occurred several times a week, typically triggered during meetings where he needs to think and speak. Casual conversation and cognition does not seem to trigger this. Workup revealed a heterogeneous plaque affecting the left ICA with velocities in the 60-79% range. CTA confirmed this plaque. MRI failed to show any stroke or other lesions. Neurology evaluation showed normal exam. The patient underwent endarterectomy, and had a normal recovery. In followup, he denied any further episodes of aphasia.

Standard endarterectomy with patch

Aphasia, the loss of function in the language centers, typically of the left brain, although in a minority, it may live in the right hemisphere, is terrifying manifestation of stroke. This case, if examined superficially, is nothing special in that TIA’s associated with a reasonable culprit lesion went away after elimination of that culprit lesion. To me, it was fascinating because it represents a possible case of brain claudication.

The human brain is believed to have evolved to its large size in conjunction with bipedalism, social hunting and gathering, and climate change in the Great Rift Valley favoring a savannah over forests, that created heat stresses on the brain, favoring the development of sweating and redundancies in brain tissue. The advent of fire and cooking enhanced available calories to feed this enlarged brain’s metabolic needs. When the metabolism isn’t supported through adequate blood supply, the brain tissue dies. Rarely, it blinkers on and off, and even more rarely, this occurs in the motor strip triggering today a neurologic evaluation including a carotid duplex that brings these patients to our attention. The fascinating question for me is, does increased metabolic demand in the form of complex thinking result in a supply-demand mismatch much as seen in exercise induced angina or claudication? If it can, can we test for it?

The tests we have available are hemodynamically based. At its simplest, after carotid angiography, an occluding balloon can be inflated to test for symptoms. This is an archaic test and I do not do it. There are nuclear medicine, PET CT, and MRI tests that use pharmacologic agents to induce hypotension, but again, for this patient, it wouldn’t apply. This patient needed the equivalent of a treadmill in the MRI machine. Maybe having him read a dry, technical treatise on neurobiology taped to the MRI tube?

I went to the OR with the indication of TIAs associated with a >50% lesion, but I did tell the patient that it was possible his thinking-induced aphasia would not remit. Thankfully it did.

Categories
MALS

A nationwide analysis of median arcuate ligament release between 2010 and 2020: a NSQIP Study

A nationwide analysis of median arcuate ligament release between 2010 and 2020: a NSQIP Study
— Read on link.springer.com/epdf/10.1007/s00464-022-09431-3

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
aortoiliac occlusive disease (AIOD) bypass chronic limb threatening ischemia Practice techniques

Durability is the Gift that Keeps Giving

The patient was a 50 something year old man who I took care of in 2016 before I left for Abu Dhabi. He had a background of hypertension, hypercholesterolemia, and IDDM with chronic immunosuppression for rheumatoid arthritis. For several weeks he had rest pain in his feet and impending gangrene of his left great toe. More worrisome was the development of punched out ulcers on his groin crease resulting in weeping wounds after a bout of cellulitis. He had no palpable femoral pulses. Pulse volume recordings showed flat lines from the thigh to the feet.

CTA of the abdomen and pelvis with runoff showed aortic occlusion due to heavily calcified plaque with reconstitution of the external iliac arteries via the internal iliac arteries. The common femoral arteries were only mildly diseased and there was patent runoff.

Centerline up right femoral into aorta shows occluded aorto-iliac segment and diseased external iliac artery.
Centerline up left femoral into aorta shows mirror image of disease on left side

He was one of the rare instances of chronic limb threatening ischemia due to aortoiliac occlusive disease, AKA Leriche syndrome. The added background of autoimmunity made him vulnerable to the ulcers in the groin crease, and the infections there made access challenging.

Leriche Syndrome

The choices were endovascular versus open surgical repair. The groins were a problem with recent cellulitis, immunosuppression and open wounds, but with careful prep, and coverage with Ioban, access was possible, even for stent grafting. The problem was the aortic bifurcation was heavily calcified, and manipulating this likely thrombotic material with an end stump of aorta can cause renal embolism. There was a small risk of rupture at the bifurcation and of renal failure.

Standard aortobifemoral bypass graft was out of the question because of the lack of a safely clampable aorta -there was circumferential aortic plaque below and above the renal arteries and the infections in the groins would jeopardize any prosthetic graft. You have to respect unclampable aortas but like anything else, there are ways around it (link).

Regarding the groins, during fellowship, Dr. Thomas Bower used to take the distal anastomoses to the external iliac arteries which could be exposed via short lower abdominal incisions if not through the midline incision itself, avoiding groin incisions in hazardous groins.


I performed an aorto-bi-iliac bypass using the balloon in the infrarenal technique after obtaining supraceliac control described in my technical post (link).

A small aortotomy can be controlled with a finger and a foley easily slipped in -just remember to clamp it
This typically provides adequate hemostasis and space to perform a proximal anastomosis

I was able to endarterectomize a nice segment of aorta and anastomose end to side -always end to side as it preserves endovascular options. The distal anastomoses was to the external iliac arteries. He did well in the immediate postoperative period but I soon left for Abu Dhabi.

In the five years since the operation, he has needed an SMA stent and has devloped worsening CKD and autoimmune diseases. But one of the gratifying things is he healed his wounds on this groins and thighs and the left hallux, and pain has never recurred. He had a contrast CT at the 5 year point (figure) showing a widely patent graft, and he sought me out when he heard that I was back in Cleveland.

His PVRs remain normal (figure).

The PVRs and ABI’s remain robustly normal even after 5 years

I’m not saying that iliac stents from the iliac bifurcation to the renal arteries was a bad option, but there is a particular sadness and weariness when I have to take care of occluded stents. As an engineer, what is worse than ballooning an occluded stent and placing another stent inside? Knowing what I know about cell biology, what is worse than lasering, drilling, cutting, that cicatricial scar tissue that is neointimal hyperplasia in terms of what you leave behind. This man still has decades left to live and he will have his bypass graft far longer than any stent. This durability, a byproduct of the technique, is a worthy virtue.

When I operated, he was in his mid fifties and despite his comorbidities, was able to undergo a big operation. Now he is in his sixties and his autoimmune issues have progressed to where he is suffering from stiff person syndrome with difficulty walking. His renal function is poor and overall he is a terrible open surgical candidate. If I had done interventions at that time, which I was tempted to, he could today be facing amputations in the setting of cytotoxic immunosuppression having run out of endovascular options.

We have lost too much to innovation. The fact is, aortic surgery for critical limb ischemia was once and it still is a thing, because it works.