The Closest Thing to an Off Pump CABG -a Carotid Subclavian Bypass to Treat Unstable Angina

 

Patient is a 77 year old man with history of HTN, hyperlipidemia, former smoking, and CAD with CABGx5 and bilateral lower extremity bypasses who developed unstable angina consisting of neck and throat pain. He underwent catheterization at an outside hospital and found to have 100% LAD occlusion, a diseased, small patent left main and left circumflex (the profunda femoral artery of the heart!), 100% RCA occlusion, a patent but diseased SVG to distal RCA, and a patent LIMA graft to distal LAD but with severe plaque and near occlusion of his proximal left subclavian artery.

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He had an NSTEMI. His vitals signs stabilized in the coronary care unit and he was sent to a telemetry floor. Whenever he walked, he would get the jaw pain, and this would also occur sporadically while recumbent.

On examination, he had no left brachial pulse, only a monophonic signal there, and bounding femoral pulses where there were the origins of bilateral femoral-tibial bypasses. His radial artery pulse was diminished on the right and absent on the left. Both saphenous veins had been harvested as were arm veins for the left leg bypass.

CTA shows the left subclavian artery to be occluded at its origin.

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Heavily calcified occlusive plaque in left subclavian artery
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Arrow points to LSCA origin with plaque

Cardiac surgery, interventional cardiology, and vascular surgery were called in for consultation. Cardiology consultation (Drs. Kapadia and Shisheboor) felt, and I agreed, that the left subclavian lesion was a poor candidate for recanalization and stenting. CT Surgery (Dr. Faisal Bakaeen) and I had a long discussion regarding alternate conduits, as he had unknown radial but likely radial artery disease, and had all usable veins previously harvested. I brought up a free RIMA graft -I had worked with Dr. Daniel Swistel, in NYC as a resident, who was Dr. George Green’s protege, and as a medical student at P&S I scrubbed Dr. Green’s final cardiac case. He routinely performed bilateral ITA bypasses decades before all-arterial revascularizations were routine. I get enthusiastic talking about cardiac disease! Walking through all the options -does anyone use deep femoral vein as coronary bypass conduit -we agreed ultimately that the best option would be a carotid-subclavian bypass with plenty of backup.

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At its heart, it would be this vascular surgeon’s attempt at an off-pump single vessel CABG (above). Preparations were made with cardiac anesthesia and cardiac surgery to place an IABP (intra-aortic balloon pump) if he became unstable. For my part, the operation was straightforward, but I was going to have to go about it efficiently. I also figured that with a clamp beyond the LIMA takeoff, no significant change would occur to the coronary flow from the LIMA graft. So I hoped as I worked very deliberately. We kept him on the hypertensive side during the case.

The operation went well. The patient’s angina resolved and a followup CT showed the patent bypass feeding the LIMA and LAD.

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LIMA bypass not well visualized on coronary CTA because of the clips used in dissecting them. Perhaps we will switch to clips that are invisible to x-ray one day. 
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Composite CTA showing the bypass

His resting angina resolved. He followed up a month later and was very pleased. Moreover, he had a brachial and radial artery pulse and a general weakness of the left arm that he never complained about before lifted.

Discussion

The carotid subclavian bypass is something that really needs to be in the armamentarium of a modern vascular surgeon. Though out of print, Wylie’s Atlas (the unabridged, multivolume version) is available used through online sellers, and is useful for elucidating the anatomy which boils down to avoiding cutting the important structures -the phrenic nerve, the vagus nerve, the brachial plexus, branches of the subclavian including the vertebral artery, while cutting away muscles -lateral head of sternocleidomastoid, any part of the omohyoid, the anterior scalene muscle. And dividing the lymphatic duct if encountered. And tunneling under the jugular vein. And minding the buttery fragility of the SCA. The best technical paper out there is by Dr. Mark Morasch and it mostly deals with carotid-subclavian transposition (reference 1) but has excellent figures on bypass as well. I do both transposition and bypass, but for brevity, I prefer bypass.

This is not a unique problem, having been reported in the literature. An unusual variant of this is coronary sbuclavian steal syndrome (reference 2), which refers to reversal of flow in the LIMA bypass in the setting of subclavian artery occlusion and left arm exertion -which was not the case here, but interesting enough to mention. Here, it was a straightforward case of managing the hemodynamics. The key point of operating on such a patient was having the surety of quick response in the case of ischemic heart failure -we operated in the cardiovascular operating rooms with rows of perfusion pumps and balloon pumps and VADs and ECMOs at the ready.  Indeed, this result could not have been so straightforward and routine seeming without the combined effort and experience of the whole Heart and Vascular Institute from nursing to consultant staff.

 

Reference

  1. Morasch MD. Technique for subclavian to carotid transposition, tips, and tricks. J Vasc Surg 2009;49:251-4.
  2. Cua B et al. Review of coronary subclavian steal syndrome. J Cardiol. 2017 Apr 14. pii: S0914-5087(17)30090-4. doi: 10.1016/j.jjcc.2017.02.012. [Epub ahead of print]

Chronic IVC occlusion causing venous claudication and ulcers requires treatment

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The patient is a gentleman from out of state who had called about problems he was having with walking and with leg ulcers that wouldn’t heal. He is in his seventies and has a pacemaker for an arrhythmia for which he was on Xarelto. He also had type II diabetes. He had bilateral lower extremity deep venous thromboses 6 years prior requiring IVC filter placement. The filter occluded, and it resulted in sudden sharp and debilitating pain in both legs with walking short distances -some days only 50 paces.He described it as an unbearable pain in calves and thighs that felt like his legs were going to burst. He also had ulcers on his legs that would heal with ministration but soon recur. This was all despite being quite active, with regular workouts, and being fit. He was compliant with compression. He sent a CT scan done last year (below).

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Right iliocaval centerline projection

It showed an Optease retrievable vena cava filter that was occluded and the iliac systems bilaterally (right above and left below) were chronically occluded with patent vena cava above and femoral confluences bilaterally below.

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Left iliocaval system showing chronic occlusion on centerline projection

He had no hypercoagulability nor ongoing recent DVT’s. I thought there was a good chance that we would be able to recanalize the occluded iliocaval segment and he flew in for a consultation, and he was pencilled into the schedule ahead of his visit.

Examination revealed a fit and trim man in his 70’s in no apparent distress. He had bilateral leg edema that was moderate with small superficial and tender ulcers of the right posterior distal calf. Pulses were normal. He was taken to our hybrid suite and venography from femoral vein access in the proximal thigh in the supine position revealed his right and left iliac venous systems to be occluded (below figures).

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Right injection from femoral sheath showing occluded iliac vein with collaterals
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Left injection

Wire access into the iliac systems was performed with Glidewire and Glidecatheter periodic venography to confirm that I had not exited the vein. Unlike the arterial system, extravasation from being extravenous does not have the consequence of bleeding, hematoma development, and pseudoaneurysm formation because of the low pressure, but it can be a long procedure and uncomfortable as well so these are done under general anesthesia.

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Advancing wire and sheath into iliac vein, crossing filter resulted in extravasation of contrast

Once position confirmed to be in the iliac vein, the vein was dilated to allow for greater ease of movement. In the case of the uncrossable filter, I switched to access from above via a right internal jugular vein access.

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Dilating vein (left) for greater mobility, and crossing from above (R. IJV access)

Once the wire crossed into the iliac vein from above, it was captured and brought out. While ballooning by itself is inadequate for revascularization, it greatly eases wire capture and on the right, it was done simply by driving the wire from above into the sheath. Wire capture wins access across the iliocaval and IVC filter occlusion from below.

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Wire passage across IVC filter into right and left systems

Once wire access is done, ballooning across the filter is done from both sides. A large sheath is them delivered across the IVC filter. Finally, a Palmaz stent mounted on a large balloon is delivered and deployed. I chose to do this from the right access, and retracted the wire on the left -something done with some trepidation because of the great difficulty gaining this access, but with with prior balloon dilatation, reaccess is made easier. Also, plan B would be reaccess from above.

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After balloon dilatation of occlusion typically to 8mm from both sides, a sheath placed and Palmaz stent deployed across filter on a large 24mm balloon

When this is accomplished, the left sided wire is reaccessed across this stent. This is the venous side analogue to gate access in EVAR (below).

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Reaccess of the left iliac venous wire across Palmaz stent

Once this is done, the iliac veins are dilated to 14mm from the IVC to the common femoral arteries. large 18mm Wall stents are deployed in a kissing fashion from the caval stent into both iliac systems and dilated to 18mm.

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Predilatation of iliac venous systems with ever larger balloons, deployement of bilateral 18mm Wall Stents

After deployment, the Wall Stents are ballooned to 18mm. These stents were extended into the common femoral artery with 14mm nitinol stents.

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Ballooning 18 mm Wall Stents with 18mm Atlas balloons, then extending to CFA with nitinol stents of 14mm

Completion venography suggested successful iliocaval recanalization and revascularization but these procedures are not done without a final intravascular ultrasound (IVUS).

Looks done, but needed final intervention after IVUS.

Intravascular ultrasound revealed incomplete expansion of the right common femoral stent. This was treated with another stent and ballooning with the result on the right.

Stent compression on IVUS treated with second stent

Venography alone is insufficient in determining patency. As illustrated, IVUS ensures a durable outcome.

The leg ulcer was treated with an Unna’s boot. A word about the venerable Unna’s boot –it works. The dressing dries and compresses while the Zinc Oxide prevents bacterial growth. It is interesting that the dressing is so infrequently used nowadays but not so when you consider that it isn’t reimbursed. And patients generally hate it.

This revascularization has an excellent chance at working as the patient has no hypercoagulability and had a patent common femoral confluence bilaterally. As I had mentioned in a prior post, the idea in venous revascularization is connecting confluences that serve as inflow and outflow.

Confluences

This will require followup, consisting of duplex, and it is advantageous that he is anticoagulated for his arrhythmia. It is becoming more apparent that those languishing with chronic venous insufficiency and its complications need the IVC and iliac veins interrogated with a duplex. When an obstruction is found, they should be treated with these techniques as a first line therapy.

 

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

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AAA with iliac arterial occlusion -arrows point to right external iliac and left common iliac arterial occlusions

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

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

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

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

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

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

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

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

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

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

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

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External iliac to common femoral artery plaque removed with Moll ring cutter (LeMaitre Vascular) over a wire

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

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

post CTA EVAR-ENDORE

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

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

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

 

Reference

  1. Hollier LH et al. J Vasc Surg 1986; 3:712-7.
  2. Nzara R et al. Ann Vasc Surg. 2015 Nov;29(8):1548-53
  3. Kavanagh CM et al. J Vasc Surg 2016;64:1327-34

SVC Syndrome: Right Internal Jugular Vein Pressure is Intracranial Venous Pressure

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The patient is a young father in his early thirties who complains of severe headaches, dyspnea, and inability to function or interact with his toddler. He complains of visual disturbancers when bending over and has dilated neck veins when recumbent. He was born with aortic stenosis and has undergone three aortic valve replacements and has had pacemakers since childhood. His most current pacemaker is a DDDR pacemaker in his left subclavian venous position, but he has two dead leads in his right subclavian vein. His symptoms started in his twenties but has worsened sharply over the past year. An effort was made to remove his dead leads at a tertiary referral center, but they couldn’t.

On examination, he had significant findings from dilated neck and supraclavicular fossa veins, a left chest pacemaker, and scars from his sternotomies. Duplex showed a patent bilateral internal jugular veins (IJV) with minimal respirophasic variability.

Venography (composite, above) showed superior vena cava occlusion consistent with his diagnosis of SVC Syndrome. I measured venous pressures, which we normally don’t do, because I was curious about them. Right IJ access with ultrasound with a sheath revealed pressures on the monitor in CVP mode of 22mmHg. Access from the groin into the heart revealed a right atrial (RA) pressure of 14mmHg. The SVC was crossed from below into the right IJV, and the SVC was dilated with a balloon -no stenting was possible because of the presence of the leads. His pacemaker did not fail during the procedure. After balloon dilatation, contrast passed easily from his IJV into his RA (below). His pressure in the R. IJV was 17mmHg and in the RA was 16mmHg.

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He immediately felt relief and in 1 month followup had sustained symptom relief with patent flows seen in right IJV. He understood it was likely he would need regular reintervention when symptoms returned.

Discussion:

While IVUS is usually the way to check on patency after venous intervention, the presence of permanent pacemaker leads, including a set of nonfunctioning leads from the right SCV, made its use moot -venoplasty to 12mm was done in multiple stations and there was to be no stenting which is the usual next step if IVUS found residual stenosis. The more interesting finding here is the pressures measured in the IJV. The symptoms of SVC syndrome come from venous hypertension, but we rarely if ever measure pressure. Intracranial pressure (ICP) which is used to monitor for critical hypertension in the cranium typically after surgery or trauma, is considered high if over 15mmHg, moderately elevated over 20mmHg, and severe when over 40mmHg. ICP is greater than or equal to intracranial venous pressure, and in patients with SVC occlusion, this pressure is equal to the IJV pressure. With an IJV pressure of 22, this patient’s ICP was likely over 20mmHg, explaining his incapacitation.

IJV pressure is easily obtained and may justify urgent intervention in acute SVC syndrome, although more data needs to be obtained. This patient will benefit most from a more durable solution, but for now, he is very pleased to be able to take part in the care of his young child.

POTS+May-Thurner’s Syndrome: Rare Disease Causes Rare Disease?

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The patient is a younger man in his twenties who began having dizzy spells associated with near syncope and tunnel vision. He was previously an athlete and was fit and never had such episodes -he had a resting heart rate typically in the 60’s or lower. Workup for arrhythmias was ultimately positive for POTS -postural orthostatic tachycardia syndrome and he was referred to Dr. Fredrick Jaeger of our Syncope Clinic. Tilt table testing the demonstrated the reported tachycardia over 140bpm while upright rising from 60bpm while supine. A radionuclide hemodynamic study (Syncope Radionuclide Hemodynamic Test) showed 54% of his blood volume pooled in his left lower extremity and lower abdomen with upright posture. Air plethysmography (PHLEBOTEST) showed abnormal refill and fill times in both legs and a duplex of the legs showed deep venous reflux in both legs. MRV revealed narrowing of left common iliac vein by the overlying right common iliac artery (May-Thurner’s Syndrome, MTS), and this was where the patient came to my clinic.

The MRV, shown above and below showed the typical pathoanatomy for MTS, but the patient had no symptoms related to left leg swelling, DVT, or varicosities. He did have a reducible left inguinal hernia which was quite tender.

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After some deliberation, while not promising anything regarding his POTS, I agreed to proceed with treating his pathoanatomy. Discussion with Dr. Jaeger revealed this: normally about 20% of blood volume parks in the legs with standing which is rapidly dissipated with normal calf muscle pump action. In a subset of patients with POTS, there is a 30-40% maldistribution of blood volume into the legs which may or may not drive the autonomic responses leading to POTS. He has never seen a study result showing a 54% distribution.

It made physiologic and anatomic sense to me to proceed with a venogram and intervention, but I confess I was dubious about any affects I might have on the patient’s POTS and I informed him of it. Also, I recommended seeing a general surgeon for his hernia.

Venography showed obstruction of his left common iliac vein as evidenced by the filling of pelvic and lumbar collateral veins.

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Intravascular ultrasound showed the narrowing better and more directly (panel below). The right common iliac artery narrowed the left common iliac vein severely.

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A 22mm Wall Stent was positioned across this and dilated with a 22mm balloon in the IVC and an 18mm balloon in the iliac vein. The resulting venogram showed resolution of the obstruction with collateral veins no longer visualized (below).

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But again, IVUS demonstrated more directly the result (and illustrates the importance of having IVUS available for venous interventions).

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The patient was discharged after procedure on a baby aspirin only. He subsequently underwent laparoscopic inguinal herniorrhaphy and returned to my clinic about a month later. His followup duplex showed a widely patent stent and normal flows in the left iliac venous system.

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Surprisingly -the patient declared that he was cured of his POTS. He said since the stents went in, he has not had any more episodes of near syncope, dizziness, tunnel vision, nor weakness requiring lying down to rest. His wife confirmed that he was a flurry of activity over the holidays that was surprising considering how debilitated he was before. This is astonishing to me.

But it should not be a surprise given this: if the POTS symptoms were the result of autonomic dysregulation, a breakdown of the feedback control loop, there were only several places this could be a problem.

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The pathology, the MTS, explains the POTS in this instance very nicely. Because the problem was in the cardiovascular system part of the diagram which I can fix and not the autonomic nervous system control element, which I can’t fix yet, a solution could be tried. This was not an asymptomatic compression of the iliac vein which we do encounter as an incidental finding. It seems to be POTS caused by MTS, and cured for now by treatment of the MTS.

 

 

The Geometry of Parallel Grafts in the Iliac Arteries

The development of metachronous common iliac artery aneurysm, or progression of them, after prior treatment with EVAR (endovascular aneurysm repair), particularly with “bell bottoming” is typically treated with coil embolization of the internal iliac artery and extension of the stent graft into the external iliac artery. While CH-EVAR has been in the news with the recent results from the PERICLES registry, I have never been entirely convinced of its durability. That is different in the case of building parallel grafts in an iliac limb of an EVAR graft (reference).

Here, the geometries, thrombosis, and forces combine to make gutter flow and endoleak unlikely. Choosing the right size of stent grafts to channel to the external and internal iliacs seems to be a challenge, but is easily solved by this scheme -which I can’t claim as my own, but was thought up by a surgeon in upstate New York who choses to remain anonymous.*

The diameter of the stent graft to be sealed to is measured and an area calculated. The sum of the areas of the two grafts to be placed need to equal or slightly exceed the area of this inflow stent graft. If you have decided the size of the external iliac graft, for example, then the diameter of other graft is merely a few geometric formulas away.

Here is a table that can be helpful in avoiding those formulas.
diameter area table.jpegThe inflow graft area is taken from its measured diameter. Then usually one or the other artery has an obligate size -a size the graft has to be while the other has more “wiggle room.” The other thing that comes from experience is that the AFX graft’s iliac limb extension don’t get the B-infolding that can affect an oversized stent graft placed in a small artery and it accomodates a neighbor well.measurement_3

For example, take this patient who after EVAR of aortic aneurysm with AFX developed metachronous dilatation of the common iliac artery to 3.9cm with abdominal pain. The average diameter is 18.5mm. From the table, that rounds to 19mm corresponding to 283.53 square mm. If the internal iliac artery requires a 13mm graft, that is 132.73 square mm, the difference being 150.80 square mm. That corresponds to a 14mm diameter graft, but a slightly larger graft is preferred for oversizing. The external iliac artery is 8mm, and putting a 13mm Viabahn (largest available) in that would result in the B-infolding in the 8mm external iliac. Here, I bailed myself out by simply placing a 20mm AFX iliac limb extension, which by virtue of its design is resistent to infolding and tolerant of parallel grafts laid alongside in constricted channels. I found that the AFX iliac limb, a 20-13mm x 88mm length extension well suited for this.

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The AFX graft limb seems to adapt to the presence of the parallel “sandwich” graft which is deployed second and ballooned last. In followup, there was shrinkage of the common iliac artery aneurysm sac and no endoleak.

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Compared to my other parallel graft case treating a metachronous saccular common iliac aneurysm years after an EVAR with a Gore endograft (link), which by table calculation, resulted in 8% oversize in calculated areas, this particular technique with a large AFX graft and an appropriately sized Viabahn seemed to work well the setting of a previously placed AFX graft. It allows one to avoid hypogastric occlusion.

The final option of a femoral or external iliac to internal iliac bypass after extension across the bifurcation to the external iliac artery is still a reasonable choice, although it seems to be receding into history.

Reference

Smith, Mitchell T. et al. “Preservation of Internal Iliac Arterial Flow during Endovascular Aortic Aneurysm Repair Using the ‘Sandwich’ Technique.” Seminars in Interventional Radiology 30.1 (2013): 82–86. PMC. Web. 9 Dec. 2016.

*While these grafts are not FDA approved for use in this manner, many times, with a prior endograft or graft in place, using the currently available and approved Gore Iliac Branch Endoprosthesis (IBE) in this common scenario would still be off label usage of an approved device, and only if it is feasible, which most times is not. For nonmedical readers, many commonly available devices and medications are used off-label, such as aspirin for blood thinning.

Bypasses still work -a guest post from Dr. Max Wohlauer

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Max Wohlauer, a recent graduate, is now Assistant Professor of Surgery at the Medical College of Wisconsin in the Division of Vascular Surgery. He sent along a case which is published with his patient’s and department’s permission.

The patient is an 80 year old man with diabetes mellitus, CHF, and pulmonary fibrosis, who presents with right foot toe ulcers. He had an inflow procedure earlier in the year, but it failed to heal the ulcers. An attempt at crossing a CTO of the SFA/POP failed. Angiogram (above), showed a distal anterior tibial artery target.

Preop ABI, TBI’s, toe waveforms, and pulse Dopplers are shown. are as shown.

 

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All point to likely limb loss. The TBI is 0 and the ABI is incompressible. Max planned for bypass. The saphenous vein was mapped and shown to be adequate.

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Max comments:

  • Compromised runoff on angio. Cutdown on AT and determined it was adequate target at start of case
  • Right fem-AT bypass
  • Re-do groin exposure
  • Translocated non-reversed GSV
  • Subcutaneous tunnel

 

The operation went well. Completion angiography was performed showing a patent bypass and distal anastomosis with good runoff.

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A followup duplex showed patency of the graft.

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Postop ABI’s showed excellent results:

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Commentary from Park

Bypasses work and are possible even in high risk individuals with good anesthesia and postoperative care. Because open vascular surgical skills are not well distributed while endovascular skills are more widely distributed, there is bias both in the popular mind and even among some catheter based specialists that bypass surgery is a terrible, no good thing. The fact is that a well planned bypass is usually both effective and durable even in high risk patients, but clearly it is not the only option.

Ongoing developments in endovascular technology bring greater possibilities for revasularizing patients. As someone who does both interventions and operations, I have seen spectacular success (and occasional failure) with both approaches, and I admit to having biases. It is human nature to be biased, but it is because of my biases, I support further ongoing study, as the mistake would be to establish monumental truths without supporting evidence. There is an ongoing randomized prospective trial (BEST-CLI) that aims to answer important questions about what approach brings about the best results in critical limb ischemia. It will bring evidence and hopefully, clarity, to this important disease.*

Finally, I am very proud to have participated in Dr. Wohlauer’s training, and look forward to seeing his evidence, experience, and even biases, presented at future meetings.

 

*CCF is a BEST-CLI study site.