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I'm still a little confused, but think you are saying the "comments above" that were your own was post 72 and 73 was partly yours and partly Catherines?

Do you know the answers to the questions I had about post 73. Or could you please ask Catherine? I THINK she is talking about the hopes for the future IF the INR is lowerred, but I could be wrong and maybe she is talking about right now.

"When you are talking about co-morbidity are you talking about the risk of bleeding because your on Coumadin or something else entirely, (I never heard people call bleeding a co-morbidity here)?

The other part that confuses me, is are you saying that hopefully if the trials go well AND On-X patients can have a lower INR THEN there will be less than the 1-2% risk of a major bleed that there is NOW or are you saying right now you have a lower chance of a major bleed with the On-X compared to the other mechanical valves on the market today?"

(BTW by right now, I mean following the guidelines and not people in the On-X trial)

Thanks

Lyn,

If you have Questions for Catheran, then ASK Catheran.
Here is her e-mail address: [email protected]
or you can call the company at 888-339-8000 (ext 265 for Catheran).
She is willing to talk to ANYONE who has questions about On-X products.
 
Lyn,

If you have Questions for Catheran, then ASK Catheran.
Here is her e-mail address: [email protected]
or you can call the company at 888-339-8000 (ext 265 for Catheran).
She is willing to talk to ANYONE who has questions about On-X products.

The reason I asked you on this thread was because you posted or passed on the information and I thought it would be good to have the answers here.
 
Jeri, I too, agonized over which valve to choose! I was 56yrs at the time of my surgery, and my surgeon said I could go either way, that's the part that made it so difficult! If I had been in my forties, or maybe even 50 I believe I would have chosen mechanical. To be honest, I didn't want to be on coumadin, because I am extremely sensitive to alot of drugs. The other reason being, the noise. I know my personality, and it would be extremely difficult for me to get used to. Having said that, there are alot of people on this forum that have done just great with coumadin, and the "ticking" of a mechanical valve!

Talk it over with your Dr's. Weigh the pros and cons of each. Then you can go with a well informed decision.
You must understand though, that your surgeon really has the FINAL say so.

Once you've had your surgery, and your well on your way to a full recovery, NEVER second guess your decision! Just take it day by day, and be thankful that we live in a time when you could have a second chance at life!!

Take care and good luck
 
Jeri, I too, agonized over which valve to choose! I was 56yrs at the time of my surgery, and my surgeon said I could go either way, that's the part that made it so difficult! If I had been in my forties, or maybe even 50 I believe I would have chosen mechanical. To be honest, I didn't want to be on coumadin, because I am extremely sensitive to alot of drugs. The other reason being, the noise. I know my personality, and it would be extremely difficult for me to get used to. Having said that, there are alot of people on this forum that have done just great with coumadin, and the "ticking" of a mechanical valve!

Talk it over with your Dr's. Weigh the pros and cons of each. Then you can go with a well informed decision.
You must understand though, that your surgeon really has the FINAL say so.

Once you've had your surgery, and your well on your way to a full recovery, NEVER second guess your decision! Just take it day by day, and be thankful that we live in a time when you could have a second chance at life!!

Take care and good luck

You are so right. I know I need to discuss this further with my surgeon. My cardio and my PCP feel that the tissue valve is better fit for me and my cardio believes that my surgeon will think so also. I really want to maintain my active life. I try to workout everyday...in the summer, I am even more active. My husband and I love to ride our motocycle and fly our airplane. We travel alot especially in the summer months and I really love to eat everything!!! I really believe Coumadin will "cramp my style". But I do love reading everyone's opinion. If I would have to go mechanical, I feel like I could handle that alot better now because of this forum ...everyone has taught me so much and I appreciate it so much. You are all so caring and passionate about your decisions and it helps to read both sides of this. I also have this aortic aneursym and I don;t know what he wants to do about that, if anything at this time. So there is much to consider. I am also really worried about my Mom's care. She just had another MI and also have a stroke shortly after. She is doing better now but I don't what will happen at discharge. But my cardio does not want me to put off this surgery. She feels it would be a big mistake for me and not an option. So there is much weighing on my mind. Thanks alot for your post. God bless you all.
Jeri
 
Clots can be formed for several reasons. One possibility is due to Eddy Currents forming in the flow pattern.

On-X is the ONLY mechanical valve I am aware of where the leaflets open a full 90 degrees to prevent turbulence in the output flow pattern. They have a very clever solution to the 'how to close a valve that is open 90 degrees' challenge.

ATS, Carbomedics, and St. Jude Mechanical Valves open less than 90 degrees to catch the 'back-flow' at the end of the 'pumping cycle' to close the leaflets. The downside of this kind of design is Turbulence in the output flow.

EDIT - The ATS Valves only open to 75 degrees according to my contact 'in the biz'.

On-X has some supporting evidence of lower complication rates in non-compliant populations (in South Africa) where they reported lower complication rates than other mechanical valve manufacturers. One of the 'other' mechanical manufacturers tried a No Anticoagulation study in Europe many years ago. It was Terminated abruptly after several patients suffered Strokes. The FDA approved ON-X Low/NO anticoagulation study is still ongoing with (presumably) good results.

Al, I've been intrigued by your comments about how far the mech-valve leaflets open (e.g., from a low of 75 degrees to a high of 90 degrees), and the effect that has on turbulence in the output flow pattern -- which I believe should affect a number of outcomes, including destruction of blood cells, hemodynamics, and maybe also valve noise. So I've responded by doing what I do (when I have too much spare time), which is doing some online research on it! :)

It seems that the On-X is, indeed, designed to open to 90 degrees, and the ATS is designed to open to 85 degrees. But it seems that both of them may ACTUALLY open LESS than those "design opening angles"! And moreover, there is some evidence that the LESSER openings may actually have some ADVANTAGES(!), despite presenting (obviously) a slightly smaller effective opening area! E.g., it seems to be widely acknowledged (=~ often repeated) in many of the studies I found that the ATS valve is the QUIETEST of the leading mech-valves, and that low noise level may be associated with the smaller "throw" of the leaflets. (One study touting the ATS as the quietest is "Evaluation of valve sound and its effects on ATS prosthetic valves in patients' quality of life" by Sezai A, Shiono M, Orime Y, Hata H, Yagi S, Negishi N, Sezai Y., Ann Thorac Surg. 2000 Feb;69(2):507-12, http://www.ncbi.nlm.nih.gov/pubmed/10735689 .)

And one study found that at least in the 29mm size, the ATS valve had the best hemodynamics (lowest pressure gradient), either DESPITE the low-angle opening, or BECAUSE of it:
"Influence of valve size on the hydrodynamic performance of the ATS valve" by Zhonggang Feng, Takao Nakamura, Tetsuo Fujimoto and Mitsuo Umezu, Journal of Artificial Organs, Volume 4, Number 4, 303-307, DOI: 10.1007/BF02480022 [2002], www.springerlink.com/content/l0055q1347046r33/ :

Cineradiography has revealed the presence of the “non-fully-open” phenomenon in patients with the ATS valve. Preliminary in vitro investigations have identified two contributing factors: the expanding space at the outlet of the valve, and the local flow in the pivot area. This further study was performed with the aim of elucidating these factors with respect to different sizes of the ATS valve. Three bileafet valves, ATS, CarboMedics (CM), and St. Jude Medical (SJM), with tissue annulus diameters of 25 and 29 mm, were studied. The hydrodynamic performance of the valves was tested at the mitral position of our own pulse duplicator. The opening angle was measured using a high-speed video camera. All the CM and SJM valves were able to open fully in these tests, whereas the 25-mm and 29-mm ATS valves opened to 75° and 82°, respectively, despite their design maximum of 85°. The ATS exhibited the smallest pressure drop of the 29-mm valves, and the SJM the smallest of the 25-mm valves. The incomplete opening of the ATS valve might be explained by the ability of its leaflets to align themselves with the divergent outlet flow, due to its unique open-pivot design. Such a feature would also exhibit a low pressure drop, as seen in the 29-mm valve. The smaller opening angle in the 25-mm valve, however, could be caused by the additional pivot-flow, which might cause greater deviation of the leaflets in the smaller valve, resulting in a higher relative pressure drop.

The same authors took another crack at this question with more valves, including the On-X, in
"In Vitro Investigation of Opening Behavior and Hydrodynamics of Bileaflet Valves in the Mitral Position", Zhonggang Feng1, Takao Nakamura1, Tetsuo Fujimoto2, Mitsuo Umezu3, Artificial Organs, Volume 26, Issue 1, pages 32–39, January 2002, onlinelibrary.wiley.com/doi/10.1046/j.1525-1594.2002.06833.x/abstract :

The performance of four 25 mm bileaflet valves of different designs was evaluated in the mitral position of our own pulse simulator. With the aid of a high-speed video camera, it was demonstrated that both the St. Jude Medical (SJM) valve (Hemodynamic Plus [HP] Series, St. Jude Medical, Inc., St. Paul, MN, U.S.A.) and the CM valve (CarboMedics, Inc., Austin, TX, U.S.A.) were able to open fully and that the CM valve fluttered much more vigorously at the fully open position than did the SJM HP valve. Conversely, neither the ATS valve (ATS Medical, Inc., Minneapolis, MN, U.S.A.) nor the On-X valve (Medical Carbon Research Institute, Austin, TX, U.S.A.) exhibited movement to a fully open configuration. The overall average opening angles of the ATS and the On-X, on 3, 4, and 5 L/min flow rate for a heart rate of 70 bpm and 5, 6, and 7 L/min for 100 bpm, were 74.8 degrees and 81.6 degrees, respectively, whereas their design opening angles were 85 degrees and 90 degrees. Pressure drops across the CM and the ATS were consistently higher than those of the On-X and the SJM HP. Closing volumes for all the valves were below 8% for a heart rate of 70 bpm. This in vitro investigation yielded the following conclusions: The ATS and On-X valves are not able to open fully in the mitral position, but this does not impair their normal function; both a larger orifice diameter and a large opening angle can decrease the pressure drop; in general, the On-X valve achieves its design goals in this experiment (i.e., it produces a lower pressure drop and lower closing volume by virtue of its large orifice and high-profile design); however, the hinge flow in the non-fully open state should be investigated further.

My recent research also found a number of sources that suggest (as I'd already concluded) that the reported differences we see in hemodynamics are usually of no practical consequence except in unusually small valve sizes and especially in cases of "donor-prosthesis mismatch". But there are other good reasons to avoid turbulence, besides hemodynamics for its own sake. And at least the first reference above suggests that the angled opening of the ATS valves leaflets may create LESS turbulence than the On-X's "straighter" opening, because it aligns more perfectly with the blood flow, which is angling outwards. It's also possible that the answer is different for Aortic and Mitral valves (and both of those studies simulated MITRAL valves), because the blood-flow angles are different.

A good and ALMOST up-to-date summary of the comparison among most popular mechanical valves, most popular tissue valves, and the comparison between them, is "Are all bileaflet mechanical valves equal?" by Halkos, Michael E; Puskas, John D, Current Opinion in Cardiology: March 2009 - Volume 24 - Issue 2 - p 136-141, doi: 10.1097/HCO.0b013e328324e698, journals.lww.com/co-cardiology/Fulltext/2009/03000/Are_all_bileaflet_mechanical_valves_equal__.8.aspx#P85 . It mentions the ongoing On-X low-ACT studies over and over, always using hopeful "waffle-words" like "may" and "holds the promise" and such. . .

Finally, we've been arguing some about a 2006(?) Quebec study that concluded that the "cutoff" between mech and tissue valves should stay at 65 and not be moved younger. www.ncbi.nlm.nih.gov/pubmed/20956488 is British study from 2010 arguing the opposite: "Microsimulation and clinical outcomes analysis support a lower age threshold for use of biological valves", by Stoica S, Goldsmith K, Demiris N, Punjabi P, Berg G, Sharples L, Large S. Heart. 2010 Nov;96(21):1730-6. According to their analysis, the cross-over (or "saw-off") "plateau", based on Life Expectancy, is between 56 and 69 for men, and between 58 and 63 for women.

I hope this helps SOMEBODY!!
 
I understand that ATS claims that their valves open to 85 degrees.

The original ATS design by Jack Bokros, Ph.D., who I believe holds a patent on the ATS design, was for an opening of 78 degrees according to my contact who works with Jack at his newest company (On-X).

I have seen a report that appears to have come from Japanese authors where the ATS valve openings were measured at 72 degrees for the larger sizes and 66 degrees for the 19 mm size. (Aoyagi S. Arinaga, S. Fukunaga, et.al. Ann Thorac Surg 2006;82:853.57)

One of our members with an On-X valve reported that an Echo Tech couldn't believe that he had a mechanical valve
because the tech could not see ANY sign of Turbulence in the output from the valve.

ONE of the side-effects of Turbulence is Eddy Currents which can foster the creation of Blood Clots.
 
Al, don't forget all the studies that show that ATS recipients have FEWER blood clots ("Thromboembolic Events") than On-X recipients, even with lower INR levels than the On-X people! EIGHT of those studies are summarized at atsmedical.com/Physicians.aspx?id=2476 , and there are some summary charts at atsmedical.com/Physicians.aspx?id=2470 .

Once again, it's great to have a theory -- like (say) that magic carbon should grow and throw fewer clots, or that a valve that opens more fully should throw fewer clots than one whose leaflets don't open as far. But if your theory isn't backed up by the evidence -- like (say) the people who get that valve DON'T grow and throw fewer clots -- then the problem is with your theory, and NOT with the facts. . .

BTW, we all know that many people are wary of mechanical valves because they're afraid they'll be bothered by the noise. atcs.jp/pdf/2007_13_3/172.pdf is the fanciest study I've seen so far on why the ATS seems to be much quieter than all the competing mechanical valves. And they suspect that the partially-opening leaflets -- which just "go with the flow" instead of going all 85 (or 90) degrees -- help make it quieter, because there's less impact when they close. I think that's just a theory, while the much lower noise level (esp. in the frequencies people can HEAR) seems to be a fact.
 
:

......and some even think it will be a disrupting noise during sex:confused2:....not a problem:tongue2::rolleyes2:

DANG! I could've had an On-X!

895698065eab13ee936745e8ba4bdbdb.png
 
Hey kids, this valve discussion could go on and on and on and on....there is no "right" or "better" choice; and just
when we think that the latest and greatest is here, then another new feature will be around the corner.
Just take a look at what kind of computers, phones, etc. we were using 10-15 years ago.

It's all about what an individual person is comfortable with and perhaps also what is available to them.
Remember that VR.org has a few members leading full and productive lives with recalled valves inside of them;
there are always exceptions to the norm.

Thank you Bina!!!

I like this post!
 
Al, the ATS website I linked compares the rate of THROMBOEMBOLIC EVENTS (not just "Bleeding Problems") in a number of studies, with the ATS valve at LOWER INRs, and with the On-X at REGULAR INRs. And they do that for the Aortic position and the Mitral position, equally. Apples and apples, right? And lower INR would tend to INCREASE the rate of THROMBOEMBOLIC EVENTS (= TE =~ "thrown clots"), right?

But the Linearized Rate of TE for the ATS valve with LOWER INRs (in Aortic position) is 0.7% and 1.1% in the two listed studies, while the Linearized Rate of TE for the On-X valve with REGULAR INRs is 1.5%, 0.9%, and 1.3% in the three listed studies. The On-X had a slightly HIGHER rate of clot-throwing than the ATS, with HIGHER INR! That suggests to me, as the ATS folks suggest, that On-X's "magic carbon" may NOT be preventing thromboembolic events, or it might not be doing it as effectively as the clever design of the ATS valve's hinges.

If you look a little lower on the ATS page I linked, you can see the results for the MITRAL position, where the ATS valve knocks the On-X completely out of the water:
ATS: 0.4%, 0.45%, & 1.1% linearized rate of TE,
On-X: 1.6%, 1.6%, & 1.7%!!
Again, the ATS results are with LOWER INR, and the vastly inferior On-X results -- almost THREE TIMES as many clotting events!! -- are with REGULAR INR!!

It seems only logical to assume that the ATS would have had even BETTER TE-rate results with REGULAR INR than it did with LOWER INR, so it also seems logical to conclude that -- assuming that most or all of these study results are true and representative and replicable -- the ATS Open Pivot valve is MUCH less prone to throw a clot (= cause a ThromboEmbolic event) than the much-vaunted On-X valve, especially in the (somewhat more clot-prone) Mitral position.

Al, do you find any Oranges in that apple sauce? :)

RE: Apples and Oranges

When comparing studies it is important to verify that the studies were conducted using the same protocol and counted the same types of exceptions.

In Single Center Studies, I 'expect' that the Study Co-ordinator can establish whatever study critera and patient eligibility he wishes. Examples of Study Criteria include Patient Eligibility (Low Risk vs. High Risk, Old vs. Young, Patients with only one medical issue vs. patients with multiple medical issues, and the BIGGIE, do they count only Major Events or Both Major and Minor Events? I have seen 'reports' that suggest there are studies which only count Major Events while others include both Major and Minor.

It is *my* understanding that some studies used an INR of 1.5 to 2.5 as their definition of Low Anti-Coagulation. I would want to know if studies counted only Major Events or Both Major and Minor Events and I would want to know more about the Patient Eligibility criteria for each study being compared.

Hopefully Multi-Center Studies would be conducted under the same criteria.
FDA approved studies are monitored to verify that the Same Protocol and Same Measurement Criteria are used by All Centers.

Before accepting Study Results as equivalent, I would want to Verify that the same Criteria were used by all centers.

Apples and Oranges?

'AL'
 
Lyn,

If you have Questions for Catheran, then ASK Catheran.
Here is her e-mail address: [email protected]
or you can call the company at 888-339-8000 (ext 265 for Catheran).
She is willing to talk to ANYONE who has questions about On-X products.

Hi Al,

I decided to do just that. This is what Ms. Burnett had to say:

* The St. Jude valve was altered in fairly recent history in order to have a larger *effective* aperture than a same-size On-X valve. All other valves of the same measured size have the same effective aperture as On-X.

* The recently posted interim results of the On-X clinical trial (http://www.onxlti.com/2011/04/on-x-heart-valve-proact-trial-report/) report composite values because there is not yet enough data to compare bleeding and thromboembolism separately between the study and control groups (she said if you look at the numbers individually, though not significant, you will see more te for the study group (low INR) and more bleed for the control group (normal INR).

* They will be presenting 4 new papers in June, one of which is a 10-year longitudinal study of the On-X valve and the other is on the S. African data with low-compliance populations

* The low INR study group is full in the clinical trials, but there's plenty of room left for people in the plavix/aspirin group. The reason for this is that to qualify for the aspirin/plavix group a person has to be sensitive to both (is this difficult?)

She was quite forthcoming and intends to send me some papers. I'll report any interesting findings.

Regards
pem
 
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