Confused, please provide guidance and input

[PJmomrunner]

Hey Karla:

I've been thinking about you....

"Hemi" means half, that's for sure, but I can't find anything that defines a hemi arch procedure as one half or the other of the arch. It seems like it can be either half, but I do think my proposed surgery would also be called hemiarch (although that term was not used by my surgeon). ("Half" seems like an odd characterization for something that, to this layperson, seems to be divided into thirds. ) Maybe hemiarch is what they call it when it's not total arch?

P. J.

Can someone explain precisely what a hemiarch procedure is? Also, what a hemiarch procedure is versus what P.J. talked about above (replacing the entire ascending aorta through the inominate and left common carotid arteries)?

How common are these procedures for bicuspids? Have others on VR.com had them?

My pre-surgery consult is Tuesday with surgery to follow Wednesday. I'm in the same boat as you guys, with an ascending aneurysm and bicuspid aortic valve, and I'm making a list of questions for my surgeon.

So I want to be sure to ask him about these things...if I can understand them!

 

[PapaHappyStar]

I don't disagree with Burair's assessment that younger people have faster metabolisms. I think that's causative. I don't think it explains just what the mechanism is, though.

The calcification seems to be related to the body determining that the valve is not healthy tissue (accurate, but we wish the body would ignore that). The body calcifies things to coat and "protect" them from damage, based on some chemical cue it receives from the epithelium. Unfortunately, in a valve that requires flexibility, that's not such a great thing.

If they knew more, they might be able to do an even better job of keeping the valves from mineralizing. As it is, the various processes attempt to do away with chemicals on the valve, and in the valve's material, that attract or combine with calcium.

Please understand that it's not known for sure that these valves with their new treatments won't last their full expected lifetimes in young people, but the odds are stacked against it. Time will tell us how well they did. Hopefuly they will last significantly longer than they used to, though: common sense says they should.

If I were to guess at their potential longevity in a 35-year-old, it would be in a range of 8-16 years, averaging about 12. But I truly don't know. No one does, yet. I had my AVR at age 51, and I'm hoping for 18 years out of mine. It is a newer one, and has one of the anticalcification treatments. I'll let you know how it does.

They're great while they last, though.

Best wishes,

Dont know where I made any assessment, I am not qualified to do anything of the sort anyway....

Lets try to reason through this though:

Given younger people have higher metabolic rates ( i.e. chemical reactions proceed a bit faster maybe because enzyme production in the body is more efficient ) then dead or foreign material will be broken down and metabolized faster. Any non-native tissue/material in an object in the circulation will be broken down at a rate determined by ( at a simple level ) the age of the individual, type of material, location/stress on the object.

I dont know the details of how calcification would proceed but if I were to guess ( like Bob mentions above ) I would say when cellular integrity at a boundary layer is breached some mechanism in the body binds stuff that forms the calcific layer to prevent further deterioration. Living tissue also degrades at some rate and so you have senile calcific stenosis when tissue repair does not proceed at rates high enough to prevent calcification of extensive tissue injury on a valve ( there are probably multiple non-equlibrated -- and competing -- processes that produce this -- tissue deterioration, removal of dead/damaged tissue, net rate of calcification etc. ).

If you have autologus living tissue to replace injured or calcified tissue than its an advantage being young: living tissue can be repaired faster the younger you are and the autologous tissue starts out in better shape, since its seen less wear. So the younger you are the better something like a Ross procedure would be for you. Conversely the older you get the more sense a tissue valve makes for you.

The theory is not difficult to understand -- the real art in medical research is the design of efficient experiments to isolate and control a highly multi-variate system, and try to make a qualitative understanding numerical -- I think most of the money/prestige has been on the experimental side in medicine too

 

[PapaHappyStar]

Can someone explain precisely what a hemiarch procedure is? Also, what a hemiarch procedure is versus what P.J. talked about above (replacing the entire ascending aorta through the inominate and left common carotid arteries)?

How common are these procedures for bicuspids? Have others on VR.com had them?

My pre-surgery consult is Tuesday with surgery to follow Wednesday. I'm in the same boat as you guys, with an ascending aneurysm and bicuspid aortic valve, and I'm making a list of questions for my surgeon.

So I want to be sure to ask him about these things...if I can understand them!

Here is a nice diagram I found of the heart and the aortic arch:

I would think a hemi-arch procedure would involve replacing the lower portions of the aortic arch under circulatory arrest ( probably deep hypothermic ) -- if your surgeon mentions circ. arrest you should definitely ask him about as much detail of what he plans to do and how...

 

[coryp]

Here is a nice diagram I found of the heart and the aortic arch:

I would think a hemi-arch procedure would involve replacing the lower portions of the aortic arch under circulatory arrest ( probably deep hypothermic ) -- if your surgeon mentions circ. arrest you should definitely ask him about as much detail of what he plans to do and how...

Burair,

Nice picture and you are correct about the hemi-arch. The reasoning behind it is the "infected or aneurysmed (it that a word?) tissue must be completely removed and as you can see the Ascending Aorta connects straight into the Arch. I have been told that whether the ARCH is larger or not a hemi SHOULD ALWAYS BE DONE (Yes it is done under deep hypothermic arrest) to remove any chance of another aneurysm reoccuring. Many of the surgeons just "clamp" the area as they may not be comfortable with performing the DHTCA.

That is my take

 

[Susan BAV]

Regarding Bicuspids, I also was born with a coaractation of the aorta, which was cut out and replaced with a Dacron graft nearly 26 years ago by Dr. Denton Cooley. In that surgery, they went in through my back. When we consulted with surgeons over a year and a half ago regarding my bicuspid valve failing, one thing they were especially concerned with was how the graft repair was doing. Happily, it was in excellent shape. Also, my angiogram at that time showed arteries clean as a whistle. Another nice Bicuspid perk, or so I've read .

 

[momshell7]

My two cents on tissue valves

My two cents on tissue valves

I am in no way anyone who knows anything about valves. However, my husband had his aortic valve replaced last October. He was 37 at the time. His surgeon and cardiologist both highly recommended the Magna stentless porcine valve. My husbands surgeon was Dr. Micheal Morrant at the Toledo Hospital. We found out after doing research on him and from talking to someone we know who also knows him, that he is one of the best surgeons in this country. He travels to Europe a couple times a month to teach other surgeons etc. He highly recommended this valve. He refered to it as the Mercedes of valves, not the Cadillac but the Mercedes. He said that this is a relatively new valve and is considered to be the best currently available. Of the people who have them, no one has had to have theirs replaced. He said that so far they are at 11-15 years and still going so they don't have a lifespan available for them.

I know that doesn't provide a guarentee for how long it will last, but tissue valves are improving. There was a thread on here a while back that stated something to the effect that the new tissue valves are starting to give mechanicals a run for their money. I don't remember what it was called I am sorry.

This is just my two cents worth. I believe that tissue valves are a good way to go. But the most important thing is that you get the valve taken care of which ever valve you get, because the alternative is not a good one.

Best of luck with your upcoming surgery

Michelle

 

[karlaosh]

Hi Cory:

Did Dr. Raissi say more specifically why/how bicuspids have long-term trouble with Coumadin?

Also, why the Edwards bovine pericardial valve? I know that's the one Cleveland Clinic seems to prefer, but I'm curious why Raissi likes it for bicuspids. I thought that for people with tissue issues, mechanical was the way to go because you'd be subjecting your fragile tissue to fewer surgeries.

I really wish I could have been a fly on the wall during your consult with Raissi because I have exactly the the same questions and the same issues as you do. So please indulge me in sharing as many of the nitty gritty details as possible.

THANK YOU!
Karla

 

[tobagotwo]

The simplest explanation I can find is that cows are enormous calcium pumps, and bovine tissue is more naturally resistant. Add to it the treatments to further reduce or retard calcification, and it would seem to be the most resistant of the tissue types.

As far as the Cleveland Clinic and CEPM goes, Dr. Cosgrove and others have had longstanding relationships with the development division of Edwards Lifesciences. I don't believe they'd ever do anything harmful or less than the best to any of their patients due to that relationship, but it does (or did) exist.

I am somewhat stunned at a few recent suggestions of xenograft valves for young presenters with tissue problems, too. Not that I see everything, but I've not seen anything coming in studies that indicates a greater problem with warfarin treatment for bicuspid patients. I am also unsure of why there is so much confidence in the use of the animal valves in younger patients. The numbers just aren't there yet (as they haven't been out there long enough) to back up the assumption of extended valve life in patients in their 20's or 30's. When I got mine a year ago at 51, I was warned that I might not get as long a life out of it as I would if I were 65 (something I had already accepted). And nothing on the manufacturers' websites so far says, "Eureka!"

I would love it to be so, to give people more choices. If I saw it, I would jump on it. But...I haven't seen the proof. If someone does, please post where we can see it.

Best wishes,