Cant see the video. Can you send a Google doc link and upload the video

copy paste the youtube link in your browser.

https://www.youtube.com/watch?v=zoO-mpGHD9w

Looked at it: What is the flow through the access? Do you have central vein images?

https://drive.google.com/open?id=1F4oD6JyL5AInExOXapBoT5XfDiOPuMsv
https://drive.google.com/open?id=1kSRcyfPVPU95bsaD5KgmMV-alaw0Ma8z

please try these two links sir.. hope it helps

the post has a thumbnail image of central veins and one of the above links is a video file of central venous flow..

I see collaterals in the axillary vein. Is it possible that there is a stenosis in the subclavian vein just distal to the end of the stent? Angioplasty +/- stent may be the answer.

Thanks for the comment sir.. I agree there are a few collaterals near the axillary vein..but are we seeing any clear stenosis ? The passage of contrast through the central veins look seamless without any stasi.,should I still consider angioplasty sir?

Dr Venkatesh,
To me the central stent looks good. I have had some patients where swelling in access arm is not explainable by severity of central venous stenosis, some of them having no stenosis at all. If swelling is excessive then with AV fistula, banding to reduce the inflow may help. With graft you will have to assess the anastomosis and see if reducing inflow is an option. If swelling is tolerable, then using the graft despite the swelling should be OK. I am interested in seeing what others think.

The clinical significance of central venous stenosis in the setting of a hemodialysis access is always the net balance between inflow and the degree of the fixed central resistance. Further angioplasty of residual central stenosis (likely present) might help transiently but addressing the inflow might be more helpful. I suggest a quantitative doppler study to measure the flow in the access and subsequent restriction of flow to achieve the lowest clinically useful ( 600 cc/min for example) .

I think there are 3 possible areas of stenosis: The first just proximal to the VA as collaterals are in the outflow area ( axillary vein). It appears this area has a valve. The second area is at the junction of the axillary with subclavian vein and the third just before the stent. In the cine, you can see how contrast stagnates in the outflow vein as the area central to it ( just cephalad to the axillary - subclavian vein junction) is stenosed upto the stent. I also wonder is the flow through the AVG high for the mean diameter of the central vein. I would think the central veins should be larger in this case and the stent is possible acting as a bottle neck and causing venous hypertension. What is the size of the AVG, diameter of the artery and flow through the graft?

I might add one more thing-- high flow access can cause arm edema by itself. The total flow flowing out the extremity would be the sum of the flow coming through the access plus that from the rest of the arm.

Looking at the collaterals, it seems to be either the subclavian vein lesion( just distal to the stent and near the clavicle/ 1st rib) and/ or the venous anastomosis valve is the likely culprit.

I’ve had several cases over the years where arm edema fully resolved after PTA/stent-graft at the venous anastomosis - extending through any proximal valves.

With an end-to-side graft venous anastomosis, a proximal valve can sometimes push flow retrograde down the axillary vein. With the presence of any moderate central stenosis, this can result in significant arm edema.

Flow reduction can be challenging in a graft- revision with a surgical revision with a tapered graft could be considered though.

I would PTA the central lesion and the valve proximal to the venous anastomosis - probably considering to extend a stent graft through the venous anastomosis and valve. This “seals off” the retrograde flow at the axillary vein leading to the arm.

If that doesn’t work, maybe further PTA the central stent.

If you have any access to using IVUS, it could be helpful here as well.





Iha

I think that the band-like stenosis of the axillary vein immediately Downstream from the venous anastomosis has more clinical significance than it would appear by sheer size. The reflux distally towards the elbow could potentially explain swelling of the forearm. A simple angioplasty of this lesion could be the simplest and maybe only step needed to salvage this access and improve swelling.

One measurement of pressure within the graft and calculation of the access pressure/arterial pressure ratio would indicate whether there is stenosis and whether it's contributing to venous hypertension.

thanks for the comments. i shall update you soon regarding the progress
sincerely
venkatesh

Greetings - as usual, spending precious moments of sleep to ponder the problematic.
The problem with this presentation is the lack of useful information (disclosure - did not see the cine).
1) what material was used for the graft? ( I have had a number of such complications with biological conduits, which can expand and contract with the cardiac cycle like a augmenting capacitor).
2) what is the diameter and health of the feeding artery?
3) what is the long dimension of the arterial anastomosis (they are almost always elliptical). Over 7mm is associated with excessive flow. A hypertrophied artery and large anastomosis can make the fistula an extension of the aorta.
4) What is the measured flow? Not everybody has this capacity available. (Caution - flows measured under general anesthesia or propofol infusions are falsely low due to the cardiodepressive effects of these agents). We measure flows where indicated, and routinely see flows of 2500, 3500, or up to 5000 cc/min (see drmarcwebb.com blog "Firehose fistulas"). Our concept of an ideal flow is between 1200-1500 cc/min. Banding of a four liter fistula down to below 2000 cc/min can be difficult. Banding below 900 cc/min is associated with thrombotic consequences in my experience. Reducing outflow in a hypertrophied artery can lead to arterial hypertension of the arm early, or sludging and thrombosis of the artery late (I have several cases),
5) In perplexing cases it is sometimes useful to send a catheter to the atrium, and then measure pullback pressures to identify an occult hemodynamically significant stenosis.
In general, the problem is more likely to be inflow excess rather than outflow resistance. We have seen too many central stents placed for spurious indications in this setting. Inflow reduction in my practice may be by inflow aneurysmoplasty with or without PTFE banding, inflow resection and interposition, distalization of the arterial anastomosis, or proximalization of the arterial anastomosis with reversed basilic vein or 4-7mm tapered PTFE. I do one or more flow reduction procedures a week.
It is late, and the men have come to put me away for the evening - Good luck!

There appears to be significant retrograde flow at the venous anastomosis possibly due to “inflow excess” as Dr. Webb pointed out. A simple solution would be to ligate the retrograde vessels or even simpler would be to place a covered stent at the VA. If this fails, consider inflow reduction.

I use IVUS in cases where outflow stenosis is suspected but not obvious on the DSA. Usually it confirms a significant stenosis that requires PTA.

The original case was from almost 1 1/2 years ago - any follow-up on how this was managed? What were the outcomes? I agree that IVUS would be great here, if available