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Re: Stent Fracture

Posted: Sun Nov 21, 2010 3:51 pm
by drsclafani
NHE wrote:Dr. Sclafani,
I recently ran across the following pdf PowerPoint presentation that discusses the incidence of stent fracture in the superficial femoral artery (SFA).

Stent Fractures in the SFA - Scheinert.pdf

I know that you are personally against the use of stents in the jugular veins of MS patients. I also know that several doctors are currently using stents and that many patients that have been treated for CCSVI have received stents. Some of these patients have had complications with in-stent stenosis either due to intimal hyperplasia or due to thrombosis. However, one thing that I haven't seen addressed is the expected lifetime of such stents in the jugular vein. The presentation discusses several types of stresses which could lead to fracture and some of these stresses might be found in the jugular vein. For example, axial compression of the stent might occur when one raises or lowers their head in a nodding motion and torsional strain on the stent might occur when one turns their head to look to the side. I realize that many of the stents that have been used in the jugular veins are shorter than the ones discussed for the SFA, however, the presentation still reports a fracture rate of 13.2% for stents shorter than 8 cm. My question is should patients be concerned about stent fracture in stents used for jugular veins? It is still very early in the history of stent use in jugular veins, but could such failures become more common in the not too distant future? Is the possiblity of stent fracture a reason to avoid stents in the jugular veins? The patency rate of Nitinol Smart stents reported in the presentation at only 60% after just 1 year is not very encouraging. Moreover, the patency rate of fractured stents after 20 months is also disturbingly low (around 10%).

Thanks in advance for your response, NHE
sorry i missed this question and thanks for bringing my failure to answer to my attention.

yes, stent fracture is one of the reasons i am against stenting. Not only is there stress with nodding and with neck rotation, there is also stress from shoulder motion and a stent that is used against the valvular problems at the confluens, just under the clavicle, which also moves.

In addition, some proceduralists have used balloon expandable stents and these risk being crushed by powerful forces in the neck or by external compression as well.

There are other reasons I do not want to use stents as well

Posted: Sun Nov 21, 2010 3:55 pm
by drsclafani
David1949 wrote:Are balloons filled with air or with a liquid? It just seems that if an air filled balloon were to burst it would be like a small explosion since air compressed to 14 atmospheres would expand to a much greater volume. Bursting of a liquid filled balloon would be much less dramatic.

very good point david.
we fill the balloons with a diluted contrast mixture, but still rupture is worrisome at 14-20 atmospheres of pressure. These balloons are well made. Kevlar is used in the balloon for strength.

Posted: Sun Nov 21, 2010 4:35 pm
by drsclafani
Nunzio wrote:Dear Dr. Sclafani,
in the past I was trying to make a point in treating May-Thurner syndrome in MS patient to avoid overload of the Azygous vein and this was part of your answer:
Also, i did not find any mention of treatment of the may thurner sydrome during liberation in their paper.
Now I remember that somebody mentioned that Dr.Zamboni wanted to include this in his paper but then that part was cut out but I could not remember who said it.
Now I do thanks to Cece: It was you!
The paper never really explained why robbie did that. So as i watched that first procedure in ferrara, i noted that they did a venogram of the left iliac vein and then catheterized the left ascending lumbar vein and did another venogram. I aske paolo what that was all about and he told me that they were looking for narrowing of the left iliac vein (a congenital narrowing called May thurner syndrome) and then were looking for hypoplasia of the lumbar veins. They also looked for narrowing of the vein of the left kidney. The light went off! That was why they entered from the left side.

Paolo, why didnt you say so in your paper, I asked. Because the editors cut it out for space reasons!
Now my question. Dr. Zamboni found a similar pecentage of patients with renal vein problem as iliac vein narrowing( about 4.6%)and Dr.Galeotti showed a renal vein dilation in his PDF presentation.
http://www.ospfe.it/attach/smcferrara/d ... tti%20.pdf
On page 9 it showed a pre and post renal vein dilatation pictures.
Since I never heard anybody performing a similar procedure I was wondering if the idea has been abandoned.
Thanks again
firstly, i think that stenosis of the renal vein or the iliac vein are separate entities from IJV and AZV problems. it appears that the incidence of these stenoses is the same in ms and non ms patients.
most of the time, these stenoses are asymptomatic because of the nature of the collateral circuits being different from the ijv and azv.
Sooooooo what are the indications for treating these vein stenoses? MTS is a bit simpler as complications of thrombosis of the vein do occur. when patients have iliac or femoral vein thrombosis secondary to mts, then part of the treatment is to angioplasty or stent the causative vein blockage. If it is asymptomatic, i do not believe in drive by stenting.

on the other hand if a patient has azygos vein outflow obstruction, then an alternate pathway is from the vertebral venous plexus to the lumbar veins to the ascending lumbar veins to the iliac vein into the inferior vena cava and then into the right side of the heart. so obstruction there might compound a problem of azygos vein stenosis .....in ssome such cases I would angioplasty and stent the iliac vein

Posted: Sun Nov 21, 2010 4:43 pm
by HFogerty
Dr. Scalfani: I don't belive this issue has been addressed yet on this thread (forgive me if I missed it). I was treated a little over month ago, left jugular 50% stenosed right at 75%. I have great improvements on many levels. The one thing I noticed after I went to the gym for PT was that I could sweat again. This summer when I was on vacation in New York, the temperature got over 100 degrees. I was heating up from the inside out and felt terrible. But I noticed I did not sweat, not one drop. Now, my heat intolerance is excellent compared to before (due to the sweating - thereby regulating body temperature?). How is the angio related to this improvement? (or am I just a freak of nature). Thanks, Heather.

Posted: Sun Nov 21, 2010 4:45 pm
by drsclafani
phe wrote:I have a feeling the site was down right after I posted twice yesterday.

To Dr Sclafani...thank you for your answer. I'd do my best to try and lie flat. My left leg lies flat (if my right is supported by a wedge)-maybe it would be prudent to enter via the left groin?
phe...i would prefer to go from the left side anyway. but ifr you have severe contracture, it will be very difficult to work. I might give it a try but if the flexion contracture was really significant, it might be very difficult.

There are other reasons to consider going directly into the neck:
1. inability to get a catheter across the stenosis from below
2. partial occlusion of the jugular

Posted: Sun Nov 21, 2010 4:53 pm
by Cece
drsclafani's previous wisdom on sweating: http://www.thisisms.com/ftopicp-100854.html#100854

Posted: Sun Nov 21, 2010 4:54 pm
by drsclafani
bluesky63 wrote:Hi phe. :-) I know what you mean. Good luck.

Hello again Dr. Sclafani. I have been poking through old pages, and I am just blown away. You are just amazing. "Thank you" is not adequate.

On page 32 you said "i am in the process of doing an evidence based comparison of the complications of venography, venous angioplasty and anticoagulation, tysabri, copaxone and one or two other safe therapies. . . . will get back when i have all the information"

I am curious if you have any data or impressions you could share, on or off line?

I am especially interested because I have been saying that people should draw a distinction between venoplasty and stenting -- that venoplasty is relatively benign. Am I wrong? I don't want to say something that is not accurate.
i was distracted. While reviewing this, it was clear that immunomodulation has pretty harsh side effects than venography. While doing that investigation, I could not find a single case of the "dreaded" infection of the puncture site reported in the literature going back to the 1960s. I am not saying it never could occur, just that it never has been reported in the literature in my search. Personally i have never had this happen nor heard of any serious cases of infection.

However there is much less written about venoplasty for ccsvi so we are still working on hearsay. However i think that except for stents, major side effects are less apparent. While there are patients who have had exacerbations after venoplasty, it is unclear to me how prevalent this problem is and whether it is worse than its prevalence in patients taking DMDs. We simply dont have enough facts.
I am also concerned about the potential for a rising backlash against the entire CCSVI concept because the publicity about dangers and tragic complications from lack of follow-up and medical tourism makes it sound as though the entire concept is flawed and all treatment is dangerous. It is absolutely appropriate to be disturbed about the lack of appropriate care for people who need it, but there should be a distinction between venoplasty and stenting. (Or am I being too pedantic?)

Under the right circumstances, I wonder what the actual safety profile of venoplasty (or venous angioplasty) would be. Especially stacked up against the other MS choices. Thank you so much for any thoughts. :-)

(If you have already addressed this I apologize for a repeat.)
I am very upset about issues of medical tourism, especially in light of the need for additional followup care and the apparent inability to get help in some countries when citizens return. It gets my blood boiling

I will have something more to say about that very soon.

Posted: Sun Nov 21, 2010 4:58 pm
by drsclafani
bluesky63 wrote: I am also concerned about the potential for a rising backlash against the entire CCSVI concept because the publicity about dangers and tragic complications from lack of follow-up and medical tourism makes it sound as though the entire concept is flawed and all treatment is dangerous.
on the contrary, i think that the backlash that should arise is toward the insensitivity and callous inhumanity that results from the lack of colleagiality and a lack of shared urgency about learning about the role of venoplasty in the management of ccsvi.

i shall have more to say about that soon as well.

Re: Collateral veins post-ccsvi treatment

Posted: Sun Nov 21, 2010 5:02 pm
by drsclafani
dk wrote:Dr. Sclafani,

I was diagnosed RRMS 14 years ago, but looking back realize I've had ms since I was 16 (I'm 44). The first 6 or 7 years after diagnosis I had a worse time of it, but things have settled down and my biggest problems are bladder related and constant pain/spasticity in my legs for which I receive botox injections.

I've had an mrv (I'm on your waiting list) and it looks to me like I have a bunch of collateral veins. So my theory, which could be wrong, is that at some point I grew enough collateral veins to handle a good part of the flow and that's why some of my symptoms improved.
it certainly is possible, but there are other considerations such as diet, environmental factors, current treatments you take, etc. Since we dont know why you get the exacerbation in the first place, we certainly cant tell why you havent had an exacerbation recently.

by the way, if you are going to be treated by me, i would need a doppler exam.
When I get the procedure done and if it is successful, the collateral veins will no longer be needed. But if I restenose, say a few months later, will the collateral veins still be there to handle the flow, or do they shrivel up from non-use?
Those collaterals were there and will remain there. they will shrink but not likely go away

Posted: Sun Nov 21, 2010 5:10 pm
by drsclafani
Cece wrote:To any lurking MDs, welcome, I hope you are finding this thread as educational and enjoyable as we all do.

Dr. Sclafani, that's amazing, thank you for posting those images and explaining them. I am glad too that the result for the patient was phenomenal flow. I wish the same for all of us.

My questions: are these high pressures now enough to increase the risk of rupture? Is this going beyond what Dr. Sinan had been doing, since we've been relying on his reported demonstration of safety?

In the unlikely event of rupture, what would you do? A few months back, it was said on the forum by someone that some doctor (sorry, I can dig for specifics....) had experienced a rupture and had solved it by placing a stent.
I think that the pressure is not the major concern, it is the diameter that is most important. Once Dr. Sinan showed me that the vein could tolerate the size, i decided to use them. however dr sinan is using "poor man's cutting wires" to raise the pressure effect. It just didnt seem like it would be as effective as high pressure balloons. Of course there is risk of rupture, even at 10 mm. we will have to see over time as we hear reports of rupture incidence in the literature.

i can think of three ways to reduce bleeding from tears
1. manual compression of the torn vein
2. a stent to allow blood to flow by the torn area
3. reinflation of a balloon to allow some sealing of the tear.

Posted: Sun Nov 21, 2010 5:21 pm
by drsclafani
HFogerty wrote:Dr. Scalfani: I don't belive this issue has been addressed yet on this thread (forgive me if I missed it). I was treated a little over month ago, left jugular 50% stenosed right at 75%. I have great improvements on many levels. The one thing I noticed after I went to the gym for PT was that I could sweat again. This summer when I was on vacation in New York, the temperature got over 100 degrees. I was heating up from the inside out and felt terrible. But I noticed I did not sweat, not one drop. Now, my heat intolerance is excellent compared to before (due to the sweating - thereby regulating body temperature?). How is the angio related to this improvement? (or am I just a freak of nature). Thanks, Heather.
heather

We did discuss this.
Nonetheless we forgive you absolutely and with love.

We have a sensory nervous system, we have a motor nervous system and we have an autonomic nervous system. Sweating, heart rate, bowel and bladder function and many other things are controlled by this autonomic nervous system. it is therefore not surprising that if you had some improvement in disability of the motor and sensory system, that you might also receive some improvements in the autonomic nerve function as well. Since sweating helps control the body's internal heat, it is not surprising that a return of the ability to sweat would help cool off the body's internal temperature

glad to hear of your improvements. it helps counterbalance those who do not receive benefit or who have complications

Posted: Sun Nov 21, 2010 5:23 pm
by drsclafani
whew
that was a lot of posting

i might take off the rest of the night, although i might sneak a look while watching the football game tonite. :wink:

Go Giants!

Posted: Sun Nov 21, 2010 5:28 pm
by CCSVIhusband
CCSVIhusband wrote:Dr. Sclafani

(sorry to double post).

My next question is valves of the hemi-azygos and accessory hemi-azygous ... from my very limited reading of anatomy books trying to learn here --- each of these veins has a valve at the end of them where they drain into the azygos vein?

Do you look at those valves when in there to see if they are functioning properly?

Also ... do you go into either of those veins? (do you consider them separate veins, or when you talk azygos - does that include one or both of those)?
I didn't see an answer to this, if you don't mind Dr. Sclafani. I know these pages go by fast, so thought I'd re-ask.

Posted: Sun Nov 21, 2010 7:37 pm
by Cece
drsclafani wrote:whew
that was a lot of posting

i might take off the rest of the night, although i might sneak a look while watching the football game tonite. :wink:

Go Giants!
What is all this talk of football, tonight is "The Walking Dead" night.

Go humans! :D

Posted: Mon Nov 22, 2010 5:32 am
by sbr487
Dr. S,

Some questions pertaining to blood pressure, reflux and ccsvi -

Supposing there is a reflux eventually resulting in less consumption of oxygenated blood by brain, does heart actually adjust and start puming out less blood? Quite a few people have reported that they have low blood pressure.

If this is the case, is it not possible that due to reduced blood pressure, the level of reflux itself can reduce and hence can show up as non existent in the scans?
Do you think a test like fMRI can come handy under such situations?
For example, normal & abnormal fMRI response ...

On a personal note though - I seem to be exact opposite of many MS patients. I have high BP and take medicine as a precaution.