Catheter-based valve replacement

[Roger Frank]

Just musing here...

When a tissue valve fails 10 to 15 years; could a Catheter-based valve be an option instead of a re-open?

 

[Karlynn]

Bottom line - no one really knows yet. For an otherwise healthy person who can withstand open chest procedures, many doctors believe that will be the standard for quite a while yet. Right now they are doing trials on people who wouldn't survive a full-blown surgery. The wheels of medicine turn very slowly. The question of whether these valves designed to be planted via catheter will hold up in the healthy (with the exception of the valve!) person hasn't been answered and won't be until they start trials in these types of people.

 

[ALCapshaw2]

I'm still waiting for someone to tell me the Effective Area of a Catheter place Tissue Valve vs. a Replacement Tissue Valve (via OHS).

'AL Capshaw'

 

[ChouDoufu]

http://books.google.com/books?id=4x...X&oi=book_result&resnum=2&ct=result#PPA966,M1

this here says in clinical trials of cribier-edwards, AVA increased from 0.56 to
1.69 sq.cm. would have to be smaller than ohs valve, since it is placed and
expanded inside the existing damaged valve.

but doesn't a natural valve, or ohs replaced valve, have AVA of 3-4 sq.cm.?

 

[Ross]

The jury is out on this one. The trials on the exceptions people haven't even been fully completed and already, some are jumping to the conclusion that it is fact and will be available. Like all other things medical, sounds great and all, but may never come to be.

 

[ALCapshaw2]

http://books.google.com/books?id=4x...X&oi=book_result&resnum=2&ct=result#PPA966,M1

this here says in clinical trials of cribier-edwards, AVA increased from 0.56 to
1.69 sq.cm. would have to be smaller than ohs valve, since it is placed and
expanded inside the existing damaged valve.

but doesn't a natural valve, or ohs replaced valve, have AVA of 3-4 sq.cm.?

My point EXACTLY!

Cather-placed valves are a GREAT benefit for people who otherwise would not be candidates for Valve Replacement via OHS.

I don't think you will find many Marathon Runners amongst the recipients.

'AL Capshaw'

 

[Lynlw]

http://books.google.com/books?id=4x...X&oi=book_result&resnum=2&ct=result#PPA966,M1

this here says in clinical trials of cribier-edwards, AVA increased from 0.56 to
1.69 sq.cm. would have to be smaller than ohs valve, since it is placed and
expanded inside the existing damaged valve.

but doesn't a natural valve, or ohs replaced valve, have AVA of 3-4 sq.cm.?

I don't know if this helps, I'm not sure what the AVA of a 23mm would be in OHS this one chart I found for this St Jude Medical Hemodynamic Plus valve and the one with a standard cuff look in that ball park between 1.6 and 1.7 http://jtcs.ctsnetjournals.org/cgi/content/full/122/4/691/F116205002

also The next sentence after the quoted one is
The mean gradient fell from 43 to 8.5 mm Hg, with AVA rising from 0.56 to 1.69 cm2. This large effective orifice area is achieved by associated expansion of the aortic annulus and the absence of any struts or sewing ring so that it approaches the orifice of the best stentless surgical bioprosthetic valves.

 

[ChouDoufu]

maybe we could start a poll? anyone who has a replacement valve (or
repaired valve) can list valve type, valve size, EVA from their 3-month
post-op echo.

*******************

label size > inside diameter > lab tested EVA > implanted EVA


"The manufacturer's label size (mm) expresses only an approximate size (diameter) of the prosthesis. For a stent-mounted bioprosthesis the label size correlates with the outside diameter of the stent, not the real outer diameter including the sewing ring. Stentless valves are measured by the actual diameter at the outside of the bioprosthesis, and that is the label size. The label size is always larger than the primary orifice or inside diameter of the device. The primary orifice is often referred to as the internal orifice area or the measured geometric orifice in square centimeters. The primary orifice is difficult, if not impossible, to measure in any bioprosthetic valve. The internal orifice area is always larger than the in vitro orifice area, which is measured by testing the valve in the laboratory in a pulse duplicator. The in vitro orifice area is always larger than the area measured in vivo by Doppler ultrasound after the valve is implanted..."

http://cardiacsurgery.ctsnetbooks.org/cgi/content/full/2/2003/889?ck=nck#CLINICAL_RESULTS

 

[JeffM]

I don't know if this helps, I'm not sure what the AVA of a 23mm would be in OHS this one chart I found for this St Jude Medical Hemodynamic Plus valve and the one with a standard cuff look in that ball park between 1.6 and 1.7 http://jtcs.ctsnetjournals.org/cgi/content/full/122/4/691/F116205002

also The next sentence after the quoted one is
The mean gradient fell from 43 to 8.5 mm Hg, with AVA rising from 0.56 to 1.69 cm2. This large effective orifice area is achieved by associated expansion of the aortic annulus and the absence of any struts or sewing ring so that it approaches the orifice of the best stentless surgical bioprosthetic valves.

Would that mean the same results might not be acheived in the case of a stented bioprosthetic valve? I remember discussing this with one of the techs at Medtronic and he told me the larger the orifice of the valve, the larger the effective area of the percutaneously implanted one.

 

[Lynlw]

Would that mean the same results might not be acheived in the case of a stented bioprosthetic valve? I remember discussing this with one of the techs at Medtronic and he told me the larger the orifice of the valve, the larger the effective area of the percutaneously implanted one.

I guess the best way to find out is reasearch the ava of a 23 mm stented valve (i picked 23 because that is what I have found the other info on so the numbers would cooespond better)

I found this chart http://www.sjm.com/devices/device.a...t&location=us&type=20#CompetitiveHemodynamics at the bottom of the page

 

[Bryan B]

The jury is out on this one. The trials on the exceptions people haven't even been fully completed and already, some are jumping to the conclusion that it is fact and will be available. Like all other things medical, sounds great and all, but may never come to be.

I'm with you Ross. I remember when I was first told I needed surgery I saw a surgeon the same day. He recommended the St. Jude (that's the good part), but he also said that within 5 years there would be a new ACT drug on the market that wouldn't require regular testing. Well we all know that didn't pan out. I can see this new catheter based technology becoming more routine when replacing the pulmonary valve, mostly because it's located outside of the heart, but also because the pulmonary valve isn't under the same pressure as the other 3 valves. I still think they have a long way to go before catheter based valve replacement will replace traditional OHS in valve patients that are otherwise healthy. I do think that it will have a big impact on, and increase the lifespan of patients who are poor candidates for traditional OHS. My guess is that like a lot of other medical technology, over time this procedure will gradually evolve into a viable option for 1st time VR patients. But if I needed VR right now I personally wouldn't choose a valve counting on this technology becoming available within a certain time frame.

 

[Reddog]

Replacement via Catheter

Replacement via Catheter

My cardiac surgeon told me this month that there is a reasonable chance that they will be doing catheter-based replacements on tissue-based aortic valves regularly in 10 years. But who knows what that chance really is?