Category: ivc

Categories
iliocaval venous ivc ivc filter techniques ultrasound Venous venous intervention vte

Leave Nothing Behind -IVC filter edition

Why There is a Literature on Filter Removal

A long time ago, there was the IVC clip which survives today as a vestigial CPT code. Then in the 1980’s, the Greenfield filter was introduced and changed the management of thromboembolism (reference). The explosive adoption of endovascular technology in the late nineties and early 2000’s drove the growth in implantation of newer generations of IVC filters that were designed to be retrievable. The people requesting the filters -the physicians, surgeons, and even patients looking to stop taking anticoagulation, were basing their decision on common sense –“sometimes, people are vulnerable to pulmonary embolism and are at risk of hemorrhage with anticoagulation, so an IVC filter makes sense.” There was frankly a data gap -a breach into which multiple companies jumped in with their own flavor of filter. Many interventionists saw no need to be selective -these were easy to place, and easy to remove, and if they stayed in there was the excellent long term results of the Greenfield filter to cite, and their referring docs asked for it. There was also the high revenue density (revenue/time) that gave filters a gravitational pull. There were several problems with this endo-enthusiasm (like in so many other cases). In the absence of data and with the aggressive marketing, too many filters went in for weak indications. We now know that most of these filters do not behave like the Greenfield, which itself is not completely innocent. Unless followup is part of a process, many patients neglected to have their filters removed. And finally, the data caught up and failed several filters which are no longer on the market and the indication for these filters is now quite narrow.

In 2009, I was asked to consult on a young man who was hospitalized for upper GI bleeding. The EGD revealed the tines of an IVC filter poking through (the jpg is somewhere I swear). The prior year, he had been in a bad car accident and had a filter placed but never had it removed. The filter had migrated out of the IVC into the duodenum and into the spine and aorta. I removed it operatively, and that was the beginning of a series of cases, about 1-2 annually in my general vascular practice, of filters that had eroded through the IVC and was causing symptoms of bleeding or pain. The pain typically was associated with a tine touching on or eroding into the spine. Biomechanically, the IVC is a collapsible tube and all the viscera on top of it weighs about as much as an equivalent sack of uncooked chitterlings when recumbent and grinds on the filter and any sharp parts. Imagine unbending a paperclip (figure) and putting it in the belly. Over time, that clip will poke a hole in something. Why would we not expect an IVC filter to behave otherwise?

An Iliocaval Thrombosis Below a TrapEase Filter

The patient is a younger man who over a decade ago had a TrapEase permanent IVC filter placed when he had a pulmonary embolism while having multiorgan failure. He was on coumadin briefly, but in the 17 years since filter placement, never had another venous thromboembolic event, but did develop venous insufficiency and varicose veins that were successfully treated. Several days prior to admission, he had been working out and developed back pain. After trying to sleep it off, he woke with severely swollen and painful legs. On admission, he was found to have no lower extremity DVTs, but had slow flow suggesting central occlusion. An abdominal x-ray showed the TrapEase filter (image below).

CT scanning and MRV showed the occlusion of the patient’s iliac veins and erosion of the struts of the filter outside the IVC (axial images below).  

On heparin infusion and bedrest, his swelling improved and we had a chance to go over our treatment options. They included

  1. Catheter directed thrombolysis
  2. Angiojet thrombectomy
  3. Large sheath thrombectomy (link)

–with one of the following–

  1. Surgical resection of filter
  2. Endovascular retrieval of filter
  3. Balloon venoplasty and stent exclusion of the filter (link)

Catheter directed thrombolysis of such a large volume of clot in the absence of a good flow channel usually necessitates multiple days of thrombolysis with return for venography and adjustment, with a small but not zero chance of fatal or disabling hemorrhage. It is expensive -multiple ICU days, return trips to the OR angiosuite. Angiojet thrombectomy is useful for clearing smaller vessels and grafts but due to the pulsing of the jet, it has a good chance at creating pulmonary emboli if the filter’s occlusion is not complete. Plus it is expensive and limited by the volume of fluid necessary to create the suction. Large sheath thrombectomy has worked for me in the past (link), but I worry about leaving behind thrombus that would embolize when the filter is removed or pushed aside.

Endovascular removal of the filter is always an option -I have removed a Greenfield filter over two decades in. I have never been able to remove an OptEase or TrapEase filter -there is nothing easy about these. I have a picture somewhere sent to me by a trainee who was consulted on a patient whose IVC was transected during the attempt to remove one of these endovascularly. That said, both my partners Houssam Younes here in Cleveland Clinic Abu Dhabi and Christopher Smolock at Cleveland Clinic Main Campus suggested trying with a two-team approach with a 16F sheath and wire from above and a 12F sheath and wire from below. That would be contingent on being able to clear the thrombus adequately.

Surgery to remove the filter is something I am comfortable with. It sometimes is the only option (link). Several times a year, I scrub in with urologists and oncologic surgeons to remove tumor from the retroperitoneum or IVC and the exposure is straightforward. When I only need control of the IVC, I make a transverse incision slightly above the umbilicus and mobilize the retroperitoneum leaving the kidney down to expose the IVC. For the IVC and iliacs, a midline laparotomy with a Cattell maneuver allows for broad control. Surgical thrombectomy would be great if the thrombus was all fresh, but challenging if there were differing amounts of fresh and chronic occlusion. The CT scan, showing the iliac veins and IVC to be swole with clot, suggesting most of it was fresh. Neither CT nor MRV could tell me if the IVC below the renal confluence was occluded. I had to be certain.

I went over these issues in detail with the patient and we agreed to proceed with diagnostic venography to check out the clot. The verbiage of clot, tofu, and cheese (link) worked well in communicating the information needed to achieve our goal of getting the filter out and the IVC and iliac veins cleared of thrombus. I sent a hypercoagulability study (even on heparin, the genetic component is useful information) which returned negative.

The diagnostic venogram is much more than just the pictures. For me, so much information is transmitted from the tip of a Glidewire as it passes through an obstruction or clot. Venography (image below) showed the thrombus but more importantly, the wire passed effortlessly in either side, got caught up in the bottom of the filter, but I was able to get through and the 5cm of IVC below the renal confluence turned out to be patent. The wire looped easily on both sides to the full extant of the dilated vein suggesting no chronic component.

I recommended surgery in our hybrid angiography suite. It would avoid multiple days of thrombolysis and its attendant risks. It would avoid subtotal clearance of thrombus. It would avoid failed filter retrieval and bailing out by stenting the filter (link), something acceptable in an older higher risk patient but not in an active young man. It would avoid surgery after several days of failed thrombolysis. The ability to perform venography and sonography with a clamp on the IVC ensured the ability to fully clear clot. And we had cell saver. After laying out my thoughts and concerns, the patient agreed.

The patient was opened via a generous midline laparotomy. I recruited the assistance of my friend Waleed Hassen, master urologic surgeon here at CCAD, in exposing the IVC. The vessel loop in the picture (below) is around the ureter. Green arrows on the right image show the anterior struts (there are three posterior struts). I had just assisted Waleed recently in removing a metastatic testicular tumor off the IVC, aorta, and mesenteric arteries through the same exposure.

The surprising finding was the anterior hooks of the TrapEase filter had penetrated the serosa of the overlying duodenum. While not perforating, it eventually would have, as the struts had eroded through the wall of the IVC and were outside the adventitial. After heparinizing the patient, the cava was clamped above the filter and I opened the cava lontitudinally along the anterior most strut. I got the sternal wirecutters and removed the anterior three struts along with their hooks. There were large draining lumbar veins which were acting as collaterals that were ligated. The filter was removed internally in pieces leaving the posterior three struts behind as they were outside the IVC lumen. The lower cone can be seen with tissue ingrowth and chronic thrombus. It was dangerous and bloody behind the IVC and I chose to leave these struts behind as they would no longer be pressing into the spine with the filter mostly out. (image below).

The initial thrombectomy was done manually by massaging the vein from either side and up the cava -the thrombus (image below) in the basin on the left expelled as a unit with a spout of blood. Thrombectomy with a #5 Fogarty proved ineffective in the large vessel, and I resorted to using a Foley catheter, directing it left and right, with removal of some more thrombus.

Duplex demonstrated clearance of thrombus from the right iliac vein but adherent thrombus on the left. I placed an 18F sheath into the left femoral vein over a wire I had directed up and over into the right iliac system and advanced the sheath while suctioning -this collapsed the vein and allowed the sheath to scrape the walls of the vein, retrieving the final clot material in the right basin. Duplex confirmed the absence of clot in the left iliac vein. The venotomy was then closed primarily and a completion venogram was performed (below).

The patient recovered and was sent home after a duplex confirmed patency of his leg and iliac veins and IVC. He will be on 3 months of a NOAC for provoked DVT.

Discussion:

Most of these filters can be retrieved with endovascular techniques. The principle is of gaining control of the top of the cone and collapsing it like an umbrella. For the Cordis TrapEase and OptEase filters, both cones have to be collapsed, and the struts which will have grown into the walls of the IVC have to be be stripped away from the IVC. I had attempted removal of an OptEase with control from above when I was in Ohio, but like in this case, the filter had tissue ingrowth on the lower cone making looping and control of the filter difficult as the hook was encased. While I was able to collapse the filter into a 16F sheath supported through an 18F sheath, it was clear the IVC was invaginating into the sheath and with enough force, I would tear the IVC. It is not the worst thing, perforating the IVC, as it is a low pressure system, and a small perforation is tolerated, but a large one needs operative repair. This can be avoided with surgical removal of the filter.

Performing this in the hybrid suite allowed for complete clearance of thrombus. That said, the thrombus in the internal iliac veins likely did not come out, nor did I seek to clear them. Rather, I will rely on systemic anticoagulation to do this for me.

I use duplex sonography intraoperatively liberally during my procedures. During EVAR, transabdominal ultrasound is sufficient in ruling out or specifying endoleaks. During complex kidney transplantation which I sometimes participate in, duplex is a critical tool for evaluating flow. In this case, images showing a cleared vein (will post, currently stuck in portable ultrasound memory) assured me that I could open the clamps with confidence that pulmonary embolism could be avoided. Gratifyingly, the patient had immediate reduction of leg swelling and can be expected to avoid problems as nothing (such as stents) was left behind in the vena cava lumen.

References

  1. J-P Galanaud, J-P Laroche, M Righini. J Thromb Haemost 2013;11(3):402-11. doi: 10.1111/jth.12127.
Categories
iliocaval venous ivc Nutcracker Syndrome Ovarian Vein Pelvic Congestion Syndrome techniques ultrasound

Nutcracker Syndrome: The Renal Vein Transposition

sketch1496836916917.png

Case Report

Patient is a 43 year old woman who had been having bouts of severe left sided abdominal pain for several years with worsening episodes of nausea and vomiting resulting in several visits to the emergency room. She has also had microscopic hematuria. Gastrointestinal workup including gastric emptying study, esophagogastroduodenoscopy and colonoscopy were negative, as was a workup for kidney stones. Eventually she was referred to my clinic for management of nutcracker syndrome. She denied lower abdominal pain nor excessive menstrual bleeding.

On examination, she was tender over the left kidney and flank. Laboratory examination was positive for microscopic hematuria. CT venography (below) showed an obstruction of her left renal vein by the superior mesenteric artery. Drainage via gonadal vein was not demonstrated, and no pelvic varices or complex of retroperitoneal veins was apparent.

00084038664_20170420_1.jpg

Duplex showed the narrowing in the left renal vein and spectral Doppler showed elevated velocities across the compression caused by the superior mesenteric artery (below). The collecting system was not obstructed.

venous duplex14.jpg

PREOP DUPLEX DOPPLER.png

Treatment options included endovascularization with a large stent in the left renal vein, left renal vein transposition to a lower position on the inferior vena cava, left renal autotransplantation, and left nephrectomy. Stent placement comes with a degree of risk for cardiopulmonary embolism which may require a sternotomy to fish out an errant stent. The risk for this in the US is because the largest nitinol stents available are 14mm in diameter which might result in undersizing in a vein that could easily dilate to well over 20mm. Larger nitinol stents for venous applications are available in Europe but currently are not approved in the US (yet). Wall stents, while certainly wide enough, have the problem of being long and stiff when not fully deployed. A 22×35 Wall stent may be 50mm long if deployed inadvertently into a tributary vein or contrained at the narrowing. Because it slides easily, passing balloons in or out can cause it to slip out of position. Because this stent elongates when compressed and packed, deployment is challenging and it is prone to “watermelon seeding,” a set up for embolism. It does have the virtue of easy reconstraining.

My friend and recent host for Midwest Vascular Surgery Society Travelling Fellowship, Dr. John V. White, in Chicago, seems to have solved this problem by a multistep process of predeploying a temporary suprarenal IVC filter, deploying a stent (whatever fits), leaving the filter as a protection against stent migration for 4 weeks until the stent permanently seats itself through scarring/intimal ingrowth, then removing the filter.

I chose to perform venography and renal vein transposition. The patient was placed in a supine position on a hybrid angiographic operating room table and her right femoral vein was accessed. She was placed in 15 degrees reverse Trendelenberg which is about the upper limit possible. Venography below.

VENOGRAM.png
Arrow points to left ascending lumbar vein which is taking most of the reflux. It drains the left kidney across the midline via retroartic channels to the IVC
The films showed left renal vein compression by the superior mesenteric artery with outflow via the ascending lumbar vein, both supra and infrarenal tributaries. A midline exposure was performed and the retroperitoneum opened as in an transabdominal aortic exposure. The vena cava was exposed, and the left renal vein was mobilized by ligating and dividing its tributaries. A point 5cm below the tributary point was marked on the IVC, and this was the target for transposition.

IMG_0926.jpg

After heparinizing and clamping, the renal tributary was taken with a 5mm cuff –this would ensure proper length without narrowing the IVC.

sketch1496837342715.png

The vein was anastomosed and flow was excellent by pulse Doppler.

IMG_0927.jpg

She recovered well but had a longer stay because of an ileus, being discharged on day 5. Because she lived at a distance, and came back for followup the following week prior to boarding a plane for home. She no longer had the left sided abdominal pain and there was no hematuria. CT showed excellent drainage through the transposed vein.

pre and post ctv comparison.png

Followup will be periodic (6 monthly) renal venous duplex from home. Given that there was minimal tension on the repair, I expect this to do well.

Discussion:

Nutcracker syndrome is one of the many unfortunate consequences of our bipedal lifestyle. The small intestines hang like baggy sausages off the branched stems of the superior mesenteric artery (SMA), and in some individuals, the SMA compresses the left renal vein against the aorta. The left renal vein receives up to 12-15% of cardiac output via the left kidney, and with outflow obstruction, drains the blood through small collaterals. The renal venous hypertension results in swelling of the left kidney with subsequent left renal colic -with flank and abdominal pain, nausea, and vomiting. There is hematuria which can be gross or microscopic. With drainage via an incompetent gonadal vein, varicoceles can occur with discomfort in men and pelvic varices with pelvic congestion syndrome can occur in women.

Diagnosis is challenging because it is one of the relatively rare non-gastrointestinal causes of abdominal pain (table).

  1. Mesenteric ischemia
  2. Median arcuate ligament syndrome
  3. Nutcracker syndrome
  4. Neuromuscular
  5. Urolithiasis
  6. Inflammatory aortitis/arteritis
  7. Hypersplenism
  8. Portal hypertension
  9. Arterial aneurysm
  10. Infections
  11. Pelvic Congestion Syndrome
  12. Endometriosis
  13. Hernias 

A history of left sided abdominal pain, flank pain, nausea, vomiting, associated pelvic pain, and episodes of hematuria are diagnostic. Examination is typically positive for left renal tenderness and flank tenderness. Laboratory examination include urinalysis for hematuria. Duplex, while technically challenging, will show renal venous compression with velocity elevation or loss of respirophasicity, CTA will typically show obstruction of the left renal vein with filling of collaterals, as will MRV.

Venography should be done in a stepwise manner (White protocol) to fully demonstrate the maldistribution of blood. That is the key word, maldistribution. I learned from my fellowship with Dr. White that performing venography in as upright a position as possible recreated the pathophysiology, the physics, particularly for pelvic congestion and nutcracker. Remember, this is a disease of bipedalism, of upright posture. Many negative studies done supine become positive, as the contrast will fall to where it prefers to go. As I have stated in the past, on the venous side, demonstrating drainage has different imaging needs than demonstrating flow. Pathologic venous drainage has three characteristics:

  1. Varicose veins develop as an end stage process
  2. Reversal of flow or reflux is demonstrated, particularly into small tributary veins
  3. The midline is crossed in these usually small, now larger, collateral veins

While pressure gradients are nice if they are large, they are difficult to assess when they narrow to 1-2mmHg, particularly if they vary with cardiac cycle and respiration. Because we are assessing drainage, the distribution of contrast and the direction it goes is particularly important, and far more sensitive than pressure measurements.

Venography was done per a modification of Dr. White’s protocol for pelvic congestion:

  1. Steep reverse Trendelenberg
  2. Hand injection 10mL half diluted contrast, gently as to not create false reflux
  3. Runs with catheter in left EIV, right EIV, left renal vein, right renal vein
    1. With pelvic congestion workup, add selective bilateral gonadal and internal iliac veins.

 

I have started transposing gonadal veins when they have enlarged from chronic reflux (link, ref 2). Renal vein transposition was chosen because her ovarian vein was competent and too small to transpose (ref 1-3). While the patency rate of stents in veins seems to be acceptable, long term data is unavailable. Also, venographic appearances are deceiving -see the in-vivo measurement of the left renal vein after dissection:

IMG_0925.jpg
Left renal vein at widest is 22mm, with expansion, possibly up to 28mm, but is relatively short. Do you see the SMA?
The variability in diameter and length of the Wallstent in the 22-24mm diameter range makes this a challenging deployment. Given that I would not be able to closely follow this young patient, I felt compelled to recommend a durable solution (ref 4).

References:

  1. White, J. et al, Left ovarian to left external iliac vein transposition for the treatment of nutcracker syndrome. J Vasc Surg Venous Lymphat Disord. 2016;4:114–118.
  2. Miler R, Shang E, Park W. Gonadal Vein Transposition for the Treatment of Nutcracker Syndrome. Annals of Vascular Surgery 2017, July 6. in press. http://dx.doi.org/10.1016/j.avsg.2017.06.153
  3. Markovic J, Shortell C. Right gonadal vein transposition for the treatment of anterior nutcracker syndrome in a patient with left-sided inferior vena cava. J Vasc Surg Venous Lymphat Disord.2016 Jul;4(3):340-2. doi: 10.1016/j.jvsv.2015.09.002.
  4. Erben Y, Gloviczki P, Kalra M, Bjarnason H, Reed NR, Duncan AA, Oderich GS, Bower TC. Treatment of nutcracker syndrome with open and endovascular interventions. J Vasc Surg Venous Lymphat Disord. 2015 Oct;3(4):389-96. doi: 10.1016/j.jvsv.2015.04.003.
Categories
Gonadal Vein iliocaval venous ivc Nutcracker Syndrome Ovarian Vein Pelvic Congestion Syndrome venous intervention

Nutcracker Syndrome Pathophysiology and Pelvic Congestion Syndrome 

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Categories
iliocaval venous ivc ivc filter techniques ultrasound vascular lab Venous venous intervention

Chronic IVC occlusion causing venous claudication and ulcers requires treatment

intervention79
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).

Annotated R iliocaval Centerline Preop CT.jpg
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.

Annotated L iliocaval Centerline Preop CT.jpg
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).

right initial venogram
Right injection from femoral sheath showing occluded iliac vein with collaterals

left initial venogram.png
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.

intervention fig 1.png
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.

intervention fig 2.png
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.

intervention fig 3.png
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.

intervention fig 4.png
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).

intervention fig 5.png
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.

intervention fig 6.png
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.

intervention fig 7.png
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.

 

Categories
iliocaval venous ivc Venous venous intervention

The Cost of Success in Iliocaval Venous Thrombosis: Efficacy is Only One Aspect of Device and Procedural Innovation

preop-venous-duplex The patient is a young woman who three weeks prior to presentation developed sudden low back pain and left leg pain while exercising on an elliptical. This pain worsened through the subsequent weeks and she developed fevers, chills, and night sweats, and she came to the emergency department. There, she was found to have left thigh and leg swelling. Duplex revealed a left iliofemoral DVT starting from the iliocaval tributary and extending to her left femoral vein (figure above). A CT scan revealed a pulmonary embolism to the left lung (below). No precipitating factors were present. Vascular surgery was consulted.

ct-pe-left_1

Plan was for catheter directed thrombolysis. Venography from the patient’s popliteal vein via a short saphenous access revealed thrombotic occlusion from the left common femoral confluence to the iliocaval confluence. The thrombus was crossed, and ballooning showed there was chronicity to the occlusion in the pelvis evidenced by waisting of the balloon on inflation. A multihole infusion catheter was placed across the thrombus from the thigh to the inferior vena cava and recombinant tissue plasminogen activator was infused overnight.

pretpa-catheter-placement

The venogram from the popliteal vein showed a patent popliteal and femoral vein and the goal of this procedure became opening the common femoral  vein  and its confluence of multiple veins from the thigh, to connect it via stents to the vena cava (second image below).

femoral-vein-pre-tpa

pretpa-ivc

Clinically, there was no change overnight and when the patient was restudied next morning, there was still an occlusion starting at the common femoral vein.

post-lysis-cfv-occluded

At this point, I had a choice as to what to do next. First, I could stop, and have the patient start anticoagulation and return several months later -often, the common femoral vein returns to drain into pelvic collaterals. As I had discussed in an earlier post, venous interventions are no different from arterial ones in that inflow, draining vein, and outflow have to be considered. In the case of the veins, I like to think of it as connecting major confluences, and for a leg, the common femoral venous confluence is paramount.Confluences

Intervening from the popliteal vein to the vena cava is inferior to being able to connect draining veins at the common femoral confluence to the vena cava. So getting the common femoral vein to patency is critical, and can sometimes be achieved with anticoagulation and time. The second option is to break out a thrombectomy catheter and try to remove the thrombus by various machinations, ie. gadgets and novel catheter systems of which there are many. I felt that given the three week time course of the thrombus, the best we could get was some clearance of thrombus, leaving behind a complex network of chronic thrombus and fibrinous scar with the overnight lysis. I didn’t even try this second option and the thrombectomy machine stayed unplugged, the fancy (and expensive) catheters left hanging. The third option, surgery, was not indicated as the patient did not have signs of phlegmasia, and for the same reasons that the lysis didn’t work, opening the common femoral vein for an endovenectomy has uneven outcomes.

The fourth option, mechanical aspiration sheath thrombectomy (MAST), is a technique developed by Dan Clair, our former chair. As a concept, it is very simple. A large sheath (>12F) is introduced and the thrombus is aspirated while the bare sheath is advanced over a wire. The sheath is then removed and the contents emptied. For this case, an 18 F sheath was introduced into the femoral vein in mid thigh.

sketch24681457

The blood is ejected into a basin and a cell saver (in non-malignant cases) is used to salvage the whole blood.

thrombectomy-photo

This reopened the common femoral vein. This was for me a very important step as without achieving this, I would have had to stent into the femoral vein, excluding many smaller veins draining into the common femoral vein, and effectively basing my revascularization off the popliteal vein confluence, an inferior inflow source for venous revascularization.

post-mast-cfv
CFV post MAST

With the common femoral vein open, placing stents from the vena cava to the common femoral vein was straightforward and described elsewhere (reference). The iliac vein remained closed due to the chronic thrombosis, which was clinically May Thurner’s Syndrome, and was stented.

completion fluoro.jpg

Three things deserve comment: the vena cava and iliac veins need to be dilated up to 18mm, and larger for the cava. This is disconcerting, but size does matter. Second, IVUS is critical in confirming that everything is open. Third, the 14mm nitinol stent placed into the common femoral vein will stay open, unlike a stent placed into the artery across the inguinal ligament. It likely has to do with the deeper position of the vein in relation to the artery which protects the vein from the ligament. We don’t have the large diameter nitinol stents designed for iliocaval venous revascularization yet, but the available stents do a good job.

large-balloon-in-iliocaval-vein

The patient was discharged on anticoagulation with resolving edema in the left leg and thigh. At one month followup, duplex confirmed wide patency of the stents and IVC and no new DVT.

Discussion: MAST illustrates a critical issue for all innovation in the current setting of resource limitation. Innovations must be made with not just a consideration to efficacy and potential market, but also cost. The large sheaths used in MAST are commonly available and cheaper by multiples of tens compared to the thrombectomy systems and catheters. Unpublished data reviewing 13 patients undergoing MAST with a mean followup showed 69% with complete thrombus removal, 31% with subsegmental removal, no operative mortality, and 92% primary patency at an average of 79 days of followup, all with symptom improvement (Clair, correspondence). Other groups have reported similiar results using “large catheters” (reference 2), but nothing can compare to an 18F sheath in clearing the iliocaval system.

The patient can expect to have excellent patency in the short to mid term (reference 1).

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References

  1. Titus JM et al. J Vasc Surg. 2011 Mar;53(3):706-12.
  2. Chung HH et al. Vasc Endovascular Surg. 2016 Jul;50(5):321-7

Categories
iliocaval venous ivc Venous venous intervention

Drainage: the sewer guy knows more about veins than you would think

preintervention

Being a homeowner, you are sometimes stuck negotiating a repair with various workmen whose knowledge of building esoterica is only exceeded by their subliminal contempt of a man who can’t rip out flooring and drywall to renovate a kitchen or bathroom. I can only hope that I don’t come off that way when discussing human plumbing. It was a year into my ownership of my current home that I noticed that many of the drains in the window wells were clogged. A very unpleasant afternoon was spent digging out soil and leaves while trying to snake a coat hanger (access wire), and when I gave up, I tried to call a plumber. Only it was the wrong specialist. “You want a sewer guy.”

The sewer gentleman was a meticulously groomed Italian immigrant who walked about the house after inspecting the drain in question. After some harumphing, he declared he needed to do some tests which included running dye through the various downspouts around the house and drains in the house. Contrast drainography! To top it off, he wanted to run a camera on a flexible tube through to check out the drains. Endoscopy! Plumbing, he sniffed, was easy, but drains were an art.

For the record, our basement was dry, but I could see the money meter whirring away. It was only a few weeks removed from a spring storm where several homes a few blocks away had catastrophic flooding when rains overwhelmed the capacity of their drainage –Drainage Insufficiency!

The testing was fine, but he ended up recommending resealing the entire East side of the house and rebuilding the window wells, because while the house was dry, it was compensating by rerouting a lot of drainage down gutters and the downsloping lawn to the street –Collaterals! and he couldn’t promise the house wouldn’t flood with a torrential month of rain which Shaker Heights is prone to being downwind of the Lake.

And it is with this wisdom that I see the increasing numbers of chronic venous occlusions. For example, the patient whose venogram is pictured above initially complained to her obstetrician of persistent heaviness in the pelvis and swelling of the legs after delivering a healthy baby. MRV showed abundant pelvic collateral veins and she was referred to me.

Our first test in our clinic is a venous duplex of both legs and the abdominal veins. There was an occlusion of the inferior vena cava below the renal veins extending the the iliac veins bilaterally. I am about to give a talk on this and I composited the ultrasound.

duplex

She had iliocaval occlusion, chronic. Her symptoms were over two years, and were ever worsening. She hadn’t developed permanent skin changes of chronic venous insufficiency, but probably would in a decade or sooner. I recommended venography and an attempt at recanalization.

postintervention

The procedure went well, and her symptoms abated. For my trainees, the absence of collaterals in the after image is the sign that hemodynamically, the revascularization is the preferred route of egress. Surprisingly, this has stayed open over two years, but again, my exceedingly well paid sewer gentleman consultant, had something to say about it.

Drainage, he declared, was different from plumbing, because things move slower and there is usually solid matter -poop, leaves, dead birds, etc., to contend with. Larger, high volume drains do best with a direct in-line connection with the city sewer, while downspouts and window wells with their twists and turns and only occasional flushings clog up too well. Wise words.

It gave me a reason why iliocaval venous interventions did so much better than femoropopliteal ones.

Confluences

Venous interventions connect confluences to the main drain, in most cases the suprarenal inferior vena cava. The iliocaval segment drains the common femoral confluence, which even in the worst of chronic lower extremity DVT’s, seems to reopen with several months of anticoagulation. Not the same for the popliteal confluence which, getting much less blood flow to drain, and having a smaller diameter, stents in the femoropopliteal veins just don’t do as well. Plus, it has to drain against a greater hydrostatic pressure. The drain guy’s wisdom seems to apply. It also has implications for the kind of stents we place, and the kinds that are being developed specifically for the venous side.

 

Categories
ivc ivc filter vte

IVC Filter Migration Causing Acute Abdominal Pain

CT IVC migration_1

The patient had a carotid dissection over five years prior to presentation and had a stroke and DVT. To protect her from pulmonary embolism, an IVC filter was placed, she was anticoagulated for a while. She rehabilitated and was doing well when several months prior to consultation she developed severe upper abdominal pain that occurred intermittently without triggers. She underwent a workup which included laboratory testing and endoscopy which were negative, and a CT scan showing the IVC filter had tilted and the legs had eroded through the vena cava to abut the duodenum and abdominal aorta. No other pathology could be found and after discussion operative resection was planned.

3DVR planning

As mentioned in an earlier post, 3DVR image processing has become indispensable in planning not only aortic interventions but open surgery as well. An oblique incision was created, basically a high transplant incision, and we stayed in the retroperitoneum. The leg of the filter abutting the duodenum did not penetrate it and there was no leakage of bile. The end of the leg, of which there are two types on this filter, was in the vena cava, but the side had eroded out of the cava. Control of the IVC is always treacherous because of the fragile lumbar tributaries underneath the cava. Once heparinized and clamped, a longitudinal venotomy released the filter. The head was embedded in the cava wall and would not have been easily accessible with a snare.

removing filter

The tine that was headed towards the aorta had to be removed from the filter to manipulate it out. No bleeding was noted from the aorta.

exvivo filter

This is my fifth operative removal of an IVC filter that had eroded into adjacent organs. Recently I removed a filter which had eroded into the aorta -this required a pledgetted suture. In my first case, about 7 years ago, a filter placed in a teen, the victim of polytrauma due to an MVA, caused fevers and an upper GI hemorrhage which was diagnosed on upper endoscopy -somewhere I have a great picture of an IVC filter leg in the duodenum.

Which brings me to my last point. The guidelines for placing these filters has evolved and it is clear now that they are not as benign as once thought. They are not only associated with migration but also iliocaval thrombosis. Stenting across them can push the legs out into organs. Their migration into the retroperitoneum can cause an atypical abdominal pain syndrome -in this patient, the pain was immediately gone. If placed, plan should be made for removal if feasible, anticoagulation maintained if possible, and filter choice limited to those that have long track records.

The treatment of venous thromboembolism remains primarily pharmacologic. When the indication for the filter expires, the filter should be removed unless the risks of removal exceed the risks of leaving it in.