Very variable depending on situation. For "low flow" situations, concur that inflow banding of little utility. One possible issue with a DRIL is the interposition of graft from a reasonable proximal artery to a diseased distal target and this is a distal anastomosis right now. After an arteriogram from the most procimal feed (sometimes get lucky and find a discreet stenosis amenable to tx in a brachial artery, for example), options that might be better are to proximalize the inflow with a graft from the brachial artery to the vein near the wrist with ligation of the existing juxta-anastomotic vein. This preserves the original arterial flow to the hand. Then, should thrombosis of the graft occur, there would be comprimise of the venous outflow and usually no change in arterial flow to the hand. If this type of revision does not help, then the next serious discussion is whyer to allow comprimised arterial flow to the hand versus ligation / abandonment of the access to hpefully preserve the hand.

And sorry about my typos......I do better with CV8 suture than I do with "thumb typing" on my phone
;)

Thanks, I should have clarified- this is an upper arm fistula with a good target for a DRIL at the brachial artery distal to the anastomosis. The patient was referred for a DRIL, and I have added the images of the anastomosis and brachial artery. (These are the actual images I sent to my surgeon.)

My interest here is if there is an endovascular solution to this issue.

For those interested in high flow vs low flow steal, here's a link to this month's Endovascular Today. There's a nice article in the supplement describing this:

http://evtoday.com/2017/06/supplement

If you're bored, I have a case report in the supplement as well...

Lots of good articles in the main issue this month

http://evtoday.com/2017/06/



http://evtoday.com/2017/06/











This months issue and the supplement have some nice dialysis access articles ( including one of my cases.)

Thanks for the clarification. Traveling today and viewing and typing on my phone. All else being equal I still might favor proximilization with a graft from the axillary artery to the outflow vein at the elbow over a DRIL. Both approaches have some merit but I just don't like interposing a graft between arteries when it can be avoided. We have done some arterial angioplasty and even placed stents in a feeding artery but when a veddel is diifusely diseased, risk of atheroemboli and recurrance has got to be factored into the decision making. And, if the fistal problems are bad enough, ligating an access is more defensible than trying to preserve a fistula with an ipsilateral threatened hand. Good luck

Thanks for the clarification. Traveling today and viewing and typing on my phone. All else being equal I still might favor proximilization with a graft from the axillary artery to the outflow vein at the elbow over a DRIL. Both approaches have some merit but I just don't like interposing a graft between arteries when it can be avoided. We have done some arterial angioplasty and even placed stents in a feeding artery but when a veddel is diifusely diseased, risk of atheroemboli and recurrance has got to be factored into the decision making. And, if the fistal problems are bad enough, ligating an access is more defensible than trying to preserve a fistula with an ipsilateral threatened hand. Good luck

Thanks for the feedback!

I agree with ligation for severe cases.

I've seen more and more expert access surgeons favoring proximalization of arterial inflow (PAI) over the DRIL.

I can appreciate the advantage of proximalization, which does not involve any ligation of healthy artery.

The occasional downside however seems to be the creation of a graft/ vein "venous anastomosis."

As we know, the venous anastomosis is the Achilles heel of an AV graft. I've had cases over the years with recurrent "venous anastomosis" stenosis and thrombosis after PAI - requiring PTA / stent grafts at the newly created graft/ vein anastomosis.

On the other hand, a DRIL involves an "arterial" anastomosis graft at both ends.

This arterial anastomosis seems to hold up fairly well in the long term (in my experience). We've only rarely experienced thrombosis of the arterial-arterial DRIL bypass.

Looking at management of conventional AV grafts, we rarely experience occlusion at the arterial anastomosis, but frequently encounter venous anastomosis issues.

Any thoughts on advantages of PAI over DRIL in consideration of longer-term "venous anastomosis" patency?

For those not as familiar with the surgical options, here is a link to the options. I haven't had much experience with RUDI locally.

https://www.google.com/search?q=pai+dril&client=safari&hl=en-us&prmd=visn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjplprduPjUAhWLLyYKHbejAe0Q_AUICigC&biw=375&bih=559#imgrc=SQTg1CjcZyznIM:

Again, I would love to be able to avoid any of this with endovascular treatment of diseased forearm arteries.

In vascular surgery, we use since some years the very long dilatation balloons for small leg arteries.
Some french radiologists use also since years the dilatation of forearm arteries to improve fistula maturation.
In case of an ischemia of the hand, the first point is the flow. From my point of view, it can be about 600 ml/mn for a small fistula and about 800 for a big one. If the flow is more, I try to reduce it. In your case, I am not sure we have the information on the flow.
If the flow is normal, i dilate the calcified radial artery until the hand, using the fistula if possible. The balloon can be 2, 2.5 or 3 mm.
I can show you a case of an old woman with a very painful distal necrosis of the 2nd right finger. She had a transposed cephalic vein, with recurrent stenosis on the outflow. I coud improve the outflow with the dilatation of the vein (8 mm), and the hand by dilatation of the whole radial artery with a 2.5 or 3 mm balloon. The main problem was the recurrence of the arterial stenosis leading to some procedures. However, she died from another reason with her hand, the fistula, and no more pain.

I must apologize, but I do not see the way to send you the PP pictures!

Thanks for the feedback,

I’d love to see your PowerPoint – if you email it to me, I can try to add it to my original post to share with everyone. (the moderators of this forum should look into the possibility of allowing replies to the original post to include images and files).

dpatel@vfvascularcenter.com

The fistula was a moderate flow fistula, with a flow of 500-550 mL/min. Clinically, it did not seem that a flow reduction would be of much benefit. Additionally, there was some mild narrowing at the juxta-anastomosis already (seen in the original images posted). As mentioned before, he was referred for DRIL.
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I’m very interested in seeing if we can come up with an endovascular solution to steal. I’ve found a few small articles with some pretty remarkable results using PTA and/or atherectomy. The images in the 2nd article are quite dramatic, with a good response to PTA. Atherectomy (orbital atherectomy was used in these cases) may potentially prolong the durability of angioplasty results.

1. http://ac.els-cdn.com/S1553838916302901/1-s2.0-S1553838916302901-main.pdf?_tid=ca123732-657a-11e7-baeb-00000aacb362&acdnat=1499696550_1804373ffed0f472971386c8fe647fcf

2. https://www.researchgate.net/profile/Marco_Centola/publication/51793910_Angioplasty_of_Below-the-elbow_Arteries_in_Critical_Hand_Ischaemia/links/5623d6cb08ae70315b5db281/Angioplasty-of-Below-the-elbow-Arteries-in-Critical-Hand-Ischaemia.pdf

3. http://www.vasculardiseasemanagement.com/content/atherectomy-occluded-forearm-case-presentation-interosseous-ulnar-artery-treatment


The potential risks here involve vessel rupture, atheremboli, and vessel spasm with small vessels - however, complications rates in these studies were low. We would have to get used to using 2-3mm balloons, 0.0014 and 0.009 wires, and potentially drug coated balloons / atherectomy. Nitroglycerin was used was used for vasospasm in some studies.

Many of the cases in the studies above required eventual amputation of digits – but perhaps we can pick these cases up earlier through our regular dialysis access monitoring and surveillance protocols?

These techniques are gaining traction in the management of lower limb disease. Is the pathophysiology the same in the upper arm? Are the radial and ulnar arteries similar to the tibial artery? Is an ischemic toe similar to an ischemic finger in the presence of an AV access? Is there a true risk of complications from atheroemboli?

I think we’ll have to learn more along the way here, but this may be an area of future research. Would appreciate any positive or negative feedback.

I think that the technical problems are similar in upper and lower limb. We need small and long balloons and expertise to cross the diseased arteries. The goal is always to improve the distal arterial pressure.
The main problem in this pathology is the VERY LATE REFERRAL for most of the patients. This seems incredible for parts of the body easy to see 3 times a week. It is not like a foot or toe that can be hidden. And we can listen to the patients complaining of pain before the ulcers and necrosis.