I'm certainly not here because I'm having trouble with warfarin or my mechanical valve for that matter and need support. I'm paying back some for the help and support I got here when I was pre-op. I particularly like to reassure people who come in here upset and worried about their diagnosis or surgery, and I try to stay neutral on the BIG decision. The tissue majority may be less involved before and after for some other reason. Maybe they are just more care-free to begin with. It appears to me that for the most part this decision is not rational or fact-based but most often boils down to "gut" feeling, personal preferences and lifestyle perceptions. Those would seem to be things that are closely tied to underlying personality.
Medtronic failure rates
- Thread starter Kathy McCain
- Start date
Help Support Valve Replacement Forums:
Statistical caveats...
The valve life numbers are different for different ages. Most particularly, they run shorter in young people for tissue valves. If you're below retirement age, you should check the age basis of the numbers being thrown around by your surgeon. The ones that stuck in his head from the last valve salesman's visit may be for 65-year-olds.
Even straight numbers may not be simple. Average useful valve lifespan can be a loaded statement. Average is the arithmetic mean, which can be misleading without context. The average lifespan of a valve is not necessarily the most common lifespan of the valve.
For example, Ross interpreted the mean age of valve recipients to indicate that half the patients were under sixty-five and half over sixty-five. What the mean really indicates is that if you take all the ages of the recipients, add them up, and divide by the number of recipients, the average (mean) age is 65.
However, that mean age of sixty-five can be created by a group of people who are aged thusly: 30, 40, 70, 70, 70, 75, 80, 85. So the notion that half the people would be aged under sixty-five would be pure speculation. Outlyers, like the low ages in this group, can skew the averages. So you have to look at the attributes of your test subjects as well as read the numbers.
When talking about the lifespan of a valve, what might make sense to balance the mean in some circumstances would be the mode - the most common lifespan reached by the valve. Sometimes you can gauge it by looking at a graph shown with the study. Suppose a valve had lifespans of 1, 3, 7, 15, 15, 15, 17, 18. The mean lifespan would be just over 11 years. But the mode - the most common lifespan of the valve - would be 15 years. Taking away all other factors, more people got 15 years of use from it than any other lifespan. No one got eleven years out of it, or ten, or nine, or eight - or twelve, or thirteen, or fourteen. In fact, no one really had a lifespan anywhere close to the mean (11 years) at all.
Despite the 11-and-a-smidge-year mean, most (62% - five out of eight) of the recipients had 15 or more years of lifespan from the valve.
Best wishes,
The valve life numbers are different for different ages. Most particularly, they run shorter in young people for tissue valves. If you're below retirement age, you should check the age basis of the numbers being thrown around by your surgeon. The ones that stuck in his head from the last valve salesman's visit may be for 65-year-olds.
Even straight numbers may not be simple. Average useful valve lifespan can be a loaded statement. Average is the arithmetic mean, which can be misleading without context. The average lifespan of a valve is not necessarily the most common lifespan of the valve.
For example, Ross interpreted the mean age of valve recipients to indicate that half the patients were under sixty-five and half over sixty-five. What the mean really indicates is that if you take all the ages of the recipients, add them up, and divide by the number of recipients, the average (mean) age is 65.
However, that mean age of sixty-five can be created by a group of people who are aged thusly: 30, 40, 70, 70, 70, 75, 80, 85. So the notion that half the people would be aged under sixty-five would be pure speculation. Outlyers, like the low ages in this group, can skew the averages. So you have to look at the attributes of your test subjects as well as read the numbers.
When talking about the lifespan of a valve, what might make sense to balance the mean in some circumstances would be the mode - the most common lifespan reached by the valve. Sometimes you can gauge it by looking at a graph shown with the study. Suppose a valve had lifespans of 1, 3, 7, 15, 15, 15, 17, 18. The mean lifespan would be just over 11 years. But the mode - the most common lifespan of the valve - would be 15 years. Taking away all other factors, more people got 15 years of use from it than any other lifespan. No one got eleven years out of it, or ten, or nine, or eight - or twelve, or thirteen, or fourteen. In fact, no one really had a lifespan anywhere close to the mean (11 years) at all.
Despite the 11-and-a-smidge-year mean, most (62% - five out of eight) of the recipients had 15 or more years of lifespan from the valve.
Best wishes,
And to add more confusion to the stats. Alot of the "younger" for 30 and under or 20 and under, include the valves given to children, who usually need their valves replaced pretty often, but it isn't because the valves failed or calcified, but simply because the kids/teens outgrew their valve so it needed replaced. Often a child with the more common CHD Tetrology of Fallot, or Transpostion of the Great Vessels or Truncus, like a few member here have will go thru several pulmonary valves by the time they are 20, but the vast majority of the replacements are because they out grew the valve/conduit, but it still gets "counted" the same as a valve that is replaced by an equal size valve.
I understand the shelf life of a valve has a lot to do with the recipient's age; however, it seems odd that a 28-year-old is told a donor valve should last him 10 - 15 years, when I, who am a bit older, and therefore should have gotten more longevity, was told about 7 - 8 years. And then we have the 20- and 30-somethings here who've been told they'll get 15 - 20 years from their bovine valves, not to mention others, who are not much older, being told their bovine valve will last 30 years. That's what irks me and sounds dishonest on the part of the surgeon.
Homografts
Since I posted the studies I found for most of the other valves I thought I'd share this one I found for homografts, just because I thought it was pretty interesting, both when it started (1964) and how long some of the valves lasted. OF course it is a very small (32) group of children (mostly babies &a few toddlers) because it was about a specific CHD surgery the homografts were used for, so you can't take much from it as far as how long they should last ect. Also it shows just how rare some of these CHD /surgeries are since from 1964-2008 they only did this 32 times at this hospital.
But I thought some might be interested (It also is from the UK, all the other studies I used were US) the study is from 2010 the full Abstract is at http://www.ncbi.nlm.nih.gov/pubmed/20427059
J Thorac Cardiovasc Surg. 2010 Aug;140(2):325-9. Epub 2010 Apr 28.
Long-term follow-up after primary complete repair of common arterial trunk with homograft: a 40-year experience.
Vohra HA, Whistance RN, Chia AX, Janusauskas V, Nikolaidis N, Roubelakis A, Veldtman G, Roman K, Vettukattil JJ, Gnanapragasam J, Salmon AP, Monro JL, Haw MP.
Department of Cardiothoracic Surgery, Wessex Cardiac Unit, Southampton University Hospital Trust, Southampton, United Kingdom.
We sought to determine the long-term performance of homograft and truncal valve after complete repair of common arterial trunk. METHODS: From January 1964 to June 2008, 32 patients (median age, 14 days; range, 5 days to 2.5 years) underwent primary homograft repair of common arterial trunk. Twenty-four (75%) were neonates. The homograft used in the right ventricular outflow tract was aortic in 24 patients and pulmonary in 8 patients .....
The median follow-up was 24.5 years (range, 5.6 months to 43.5 years). ...
....The actuarial survival at 30 years was 83.1% +/- 6.6%. Of the 28 survivors, 25 reoperations were performed in 19 (76%) patients. The mean and median times to homograft reoperation were 11.5 +/- 7.4 and 12.1 years (range, 1.0-26.1 years), respectively. Overall freedom from homograft reoperation after 10, 20, and 30 years was 68.4% +/- 8.7%, 37.4% +/- 9.5%, and 26.7% +/- 9.3%, respectively. Twelve patients retained the original homografts at a median follow-up of 16.4 years (range, 0-30.2 years). Six underwent a truncal valve replacement with a mechanical prosthesis at a median of 10.5 years (range, 3.4-22 years) after truncus repair. Freedom from truncal valve replacement at 10 and 30 years was 93.1% +/- 4.7% and 81.8% +/- 8.9%, respectively. In the 22 surviving patients who did not undergo truncal valve replacement, the peak truncal valve gradient was 8.9 +/- 8.3 mm Hg at a median follow-up of 24.5 years (range, 5.6 months to 32.9 years) In the 22 surviving patients who did not undergo truncal valve replacement, the peak truncal valve gradient was 8.9 +/- 8.3 mm Hg at a median follow-up of 24.5 years (range, 5.6 months to 32.9 years). .....
Since I posted the studies I found for most of the other valves I thought I'd share this one I found for homografts, just because I thought it was pretty interesting, both when it started (1964) and how long some of the valves lasted. OF course it is a very small (32) group of children (mostly babies &a few toddlers) because it was about a specific CHD surgery the homografts were used for, so you can't take much from it as far as how long they should last ect. Also it shows just how rare some of these CHD /surgeries are since from 1964-2008 they only did this 32 times at this hospital.
But I thought some might be interested (It also is from the UK, all the other studies I used were US) the study is from 2010 the full Abstract is at http://www.ncbi.nlm.nih.gov/pubmed/20427059
J Thorac Cardiovasc Surg. 2010 Aug;140(2):325-9. Epub 2010 Apr 28.
Long-term follow-up after primary complete repair of common arterial trunk with homograft: a 40-year experience.
Vohra HA, Whistance RN, Chia AX, Janusauskas V, Nikolaidis N, Roubelakis A, Veldtman G, Roman K, Vettukattil JJ, Gnanapragasam J, Salmon AP, Monro JL, Haw MP.
Department of Cardiothoracic Surgery, Wessex Cardiac Unit, Southampton University Hospital Trust, Southampton, United Kingdom.
We sought to determine the long-term performance of homograft and truncal valve after complete repair of common arterial trunk. METHODS: From January 1964 to June 2008, 32 patients (median age, 14 days; range, 5 days to 2.5 years) underwent primary homograft repair of common arterial trunk. Twenty-four (75%) were neonates. The homograft used in the right ventricular outflow tract was aortic in 24 patients and pulmonary in 8 patients .....
The median follow-up was 24.5 years (range, 5.6 months to 43.5 years). ...
....The actuarial survival at 30 years was 83.1% +/- 6.6%. Of the 28 survivors, 25 reoperations were performed in 19 (76%) patients. The mean and median times to homograft reoperation were 11.5 +/- 7.4 and 12.1 years (range, 1.0-26.1 years), respectively. Overall freedom from homograft reoperation after 10, 20, and 30 years was 68.4% +/- 8.7%, 37.4% +/- 9.5%, and 26.7% +/- 9.3%, respectively. Twelve patients retained the original homografts at a median follow-up of 16.4 years (range, 0-30.2 years). Six underwent a truncal valve replacement with a mechanical prosthesis at a median of 10.5 years (range, 3.4-22 years) after truncus repair. Freedom from truncal valve replacement at 10 and 30 years was 93.1% +/- 4.7% and 81.8% +/- 8.9%, respectively. In the 22 surviving patients who did not undergo truncal valve replacement, the peak truncal valve gradient was 8.9 +/- 8.3 mm Hg at a median follow-up of 24.5 years (range, 5.6 months to 32.9 years) In the 22 surviving patients who did not undergo truncal valve replacement, the peak truncal valve gradient was 8.9 +/- 8.3 mm Hg at a median follow-up of 24.5 years (range, 5.6 months to 32.9 years). .....
ALCapshaw2
Well-known member
I'm still skeptical about a 30 year survival with a Bovine Pericardial Tissue Valve
(and I do believe it to be a good valve, just don't believe that 30 years is a realistic expection).
If you (or anyone) can identify the exact product name, it would be useful to contact the
product manager for that valve and ask about the longest lasting valve they are aware of.
I'm guessing it would be a Very Small Percentage of implants.
FWIW, I have seen graphs of Explants versus years of service for tissue valves expressed in percentage and they drop pretty rapidly after 10-12 years.
'AL C'
(and I do believe it to be a good valve, just don't believe that 30 years is a realistic expection).
If you (or anyone) can identify the exact product name, it would be useful to contact the
product manager for that valve and ask about the longest lasting valve they are aware of.
I'm guessing it would be a Very Small Percentage of implants.
FWIW, I have seen graphs of Explants versus years of service for tissue valves expressed in percentage and they drop pretty rapidly after 10-12 years.
'AL C'
I'm not sure if you are skeptical that any person has HADa bovine valve over 30 years, or that you can plan/hope on having one last 30 years.
I'm not sure anyone really EXPECTS their Bovine valve to last 30 years, certainly not in someone under 40. I just said it wasn't impossible mathematically, like many people believed since it has been in use closer to 30 years and not 20.
For the MOST part, I do NOT believe anyone who is not over 60 feels the odds are good that a tissue valve WILL last the rest of their lives (or even 20 years) . I BELIEVE most people in their 50s and younger plan on needing at least 1 more surgery IF they choose any tissue valve. They are fine with that, but also know that if they get a tissue valve today, at this point in time, there is a CHANCE when this valve needs replaced they MIGHT even be able to get it replaced percutaneously. I don't know of anyone counting on that, when they choose a tissue valve now, but it is a possibility. But Most people choosing tissue valve since I've been around different online heart groups, go into it knowing if they live a long happy life they WILL need this valve replaced and know the statistics are very good (as far a heart surgery statistic go) for 1st time REDOS. So it is a choice they feel is right for them.
Even the person Luana mentioned above Jendyk, who was "counting" on his valve lasting 17 years and mentioned his surgeon knew of patients that had their tissue valve 30 years, just got his valve this year so isn't expecting 30 years, but less than 20 and he is already retired. So 20 is reasonable considerring that roughly 90% of the patients over 65 still had their valve and it was doing well at 17 years. http://ats.ctsnetjournals.org/cgi/content/full/73/5/1460
Part of the problems finding enough reliable studies to even guess what the average of a tissue valve...or ANY valve in someone in their 20s or even early 30s is there really are not that many people that get their valve replaced in that age group (20-35) unless they are some of the complex CHDs that are having REDOS. BUt out of valve surgeries, which we already know are done much less than CABGs, a very small group of people getting their first valve as an adult are in their 20- 30. So there just isn't that many studies, data on that age group, compared to say 50 and up.
The latest I saw for the first set of perimounts ( the 1981-1984 group) was out of the people in their 40s Half of them (about 1/3 of the 478 were under 60 there is a break down by age at the link)
still had their valve and it was doing well at 17 years, but the other 1/2 already had it replaced. That was in the Aortic position. http://jtcs.ctsnetjournals.org/cgi/reprint/131/3/558.pdf
Most of the people that I know of that have had their tissue valve OVER 20 -25 years are in Pulmonary or on the right side, These are also fairly young people who got their valves as children or teens, when the body chemisrty is the toughest on valves.
Which makes sense,(that a tissue pulm valve SHOULD last longer) since that is one of the reasons they do a Ross procedures and take someones perfectly good pulmonary valve and put it in the Aortic position and replace the pulmonary valve with some type of tissue valve, because for the most part a tissue on the pulmonary postiion would last longer than if they put it in the person Aortic (Not ALL pulmonary valve replacements are done with tissue, but the vast majority of surgeons won't use a mechanical valve for the pulmonary valve, because the pressure is so low, even with coumadin the chances of a clot are too high)
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My docs were genuinely surprised about the reduced life of the valve, even though I am relatively young. They (the cardiologist and surgeon) were pretty adamant that the valve should have lasted longer (no guarantees of course) and given that they have both been straight shooters with me in the past, I didn't have any impression that they were being overly optimistic. It seemed they were both genuinely disappointed in the performance of the valve, especially with how well I had been doing post-op and for the first several years.
Don't know where they got their numbers from, but they consistently quoted a 15-20 year timeframe since I first started under their care. Of course, we all knew there were no guarantees....
It was almost funny how irritated my cardiologist was that the valve failed already. That was one of the reasons we were all so adamant that I go mechanical this time.
Don't know where they got their numbers from, but they consistently quoted a 15-20 year timeframe since I first started under their care. Of course, we all knew there were no guarantees....
It was almost funny how irritated my cardiologist was that the valve failed already. That was one of the reasons we were all so adamant that I go mechanical this time.
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Nancy
Well-known member
I do think the Cryolife sales people pushed that valve to the max. Several years ago, it was all the buzz here and people were absolutely convinced, as were your doctors, that this valve was the answer to tissue valve longevity. In theory, the Cryolife valve should have lasted a long time but there were some issues. You can read below about some of the issues.
I think they are still producing heart valves. There was an FDA recall on their other products, but not the heart valves.
http://www.cbsnews.com/stories/2002/08/27/eveningnews/main519937.shtml
http://money.cnn.com/2009/07/01/smallbusiness/cryolife_crisis_management.fsb/index.htm
http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PublicHealthNotifications/UCM064529
I think they are still producing heart valves. There was an FDA recall on their other products, but not the heart valves.
http://www.cbsnews.com/stories/2002/08/27/eveningnews/main519937.shtml
http://money.cnn.com/2009/07/01/smallbusiness/cryolife_crisis_management.fsb/index.htm
http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PublicHealthNotifications/UCM064529
There is absolutely an issue with the figures doctors and surgeons give for valve longevity. It really should be somehow controlled. But I don't kow how it could be done reasonably. Louana is pointing out a very common result of talking to different professionals, and it's scary. I couldn't agree with her more that this is a true concern. Most doctors/surgeons are likely not trying to be dishonest, but they don't bother to try to get the facts before opening their mouths. As they are a Trusted Source for most patients, it borders on malpractice.
We need to realize that the average score in a class is "C," and lots of doctors are average. They're also overworked and can't take the time to look into these things. That's why it can be important to look into these things yourself. Fortunately, in the end, any choice is better than no choice, so things usually work out.
Bill, I wasn't trying to imply that all mechanical users are here for warfarin support, but you have to see that the numbers are greatly askew. I am a tissue valver who never left, so I don't quite fit the bill either.
Best wishes,
We need to realize that the average score in a class is "C," and lots of doctors are average. They're also overworked and can't take the time to look into these things. That's why it can be important to look into these things yourself. Fortunately, in the end, any choice is better than no choice, so things usually work out.
Bill, I wasn't trying to imply that all mechanical users are here for warfarin support, but you have to see that the numbers are greatly askew. I am a tissue valver who never left, so I don't quite fit the bill either.
Best wishes,
I agree with what you are saying about surgeons, but I also see many surgeons, giving outdated longevity tissue stats, that are much shorter , especially in older people. Some people whose surgeons recomend mechanical valves because the tissue valves will "only" so long seem like they are going off old data/older valves too. Kind of the same numbers you often see quoted on competitive valve company sites.
I wish surgeons took the time to actually read the different studies, go to the conferences ect instead, like it seems, relying on data the valve saleman provide them.
I mentioned Jendyk not for the years but because he posted more than once that he has a "17-year warranty" for his tissue valve. Now, I don't know if he said (or in this case wrote) that tongue-in-cheek, or literally, but I took it literally. A surgeon telling a patient that he has a warranty for a specific amount of years for a tissue valve seems wrong to me; however, there is the possibility that what the surgeon said, was thus transposed by the patient's understanding to the concept of a warranty.
I took it as tongue in cheek, he seemed to enjoy the replies when he said it..but IF it was actually what he was told I agree. and IF any surgereon Gave a warranty for anything like how long a valve WOULD last, I would run..not walk in the other direction
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I tend to take things too literally. Glad to hear your take. Even without body language, hearing voice inflection and tone, can tell a lot; when I can only see words in type I tend to take them at face value.
ALCapshaw2
Well-known member
While trying to find data on the number of Mechanical and Tissue Valves implanted at Cleveland Clinic (unsuccessfully),
I came upon this information about the Bovine Pericardial Valve on the CC Website. (Can someone with a high speed internet connection find this data? My LandLine Connection is insufferably S-L-O-W. Come on ATT when is that High Speed line going to make it to my part of the county?)
From the Cleveland Clinic Website:
The Carpentier-Edwards PERIMOUNT Pericardial Bioprosthesis
Image of the PERIMOUNT Pericardial Bioprosthesis. Information and photographs posted with permission from Edwards Lifesciences®.
Heart valves built to last
This valve is made of bovine pericardial tissue (tissue from a cow heart) that has been preserved in a buffered glutaraldehyde solution and mounted on a flexible frame and a sewing ring of molded silicone rubber, which allows the surgeon to sew the valve to the patient. Both the frame and the sewing ring are covered with a knitted polytetrafluoroethylene (PTFE) cloth.
The aortic pericardial bioprosthesis has been implanted internationally since 1981, and in the United States since 1991. In the summer of 2000, Carpentier-Edwards released a PERIMOUNT valve for the mitral position.
The benefit of this valve is enhanced durability, which is related to the use of pericardium and the specific bioengineering involved in the valve design.
--------------------------------
OK, 29 years is pretty close to 30...
I would still wager that there are very few Bovine Tissue Valve still in use that were implanted in 1981,
partly because there probably were not very many implanted in 1981 when they were apparently introduced.
I came upon this information about the Bovine Pericardial Valve on the CC Website. (Can someone with a high speed internet connection find this data? My LandLine Connection is insufferably S-L-O-W. Come on ATT when is that High Speed line going to make it to my part of the county?)
From the Cleveland Clinic Website:
The Carpentier-Edwards PERIMOUNT Pericardial Bioprosthesis
Image of the PERIMOUNT Pericardial Bioprosthesis. Information and photographs posted with permission from Edwards Lifesciences®.
Heart valves built to last
This valve is made of bovine pericardial tissue (tissue from a cow heart) that has been preserved in a buffered glutaraldehyde solution and mounted on a flexible frame and a sewing ring of molded silicone rubber, which allows the surgeon to sew the valve to the patient. Both the frame and the sewing ring are covered with a knitted polytetrafluoroethylene (PTFE) cloth.
The aortic pericardial bioprosthesis has been implanted internationally since 1981, and in the United States since 1991. In the summer of 2000, Carpentier-Edwards released a PERIMOUNT valve for the mitral position.
The benefit of this valve is enhanced durability, which is related to the use of pericardium and the specific bioengineering involved in the valve design.
--------------------------------
OK, 29 years is pretty close to 30...
I would still wager that there are very few Bovine Tissue Valve still in use that were implanted in 1981,
partly because there probably were not very many implanted in 1981 when they were apparently introduced.
Yes, we mentioned a few times on this thread, that CCF and 3 other center first used it (in the US) in 81. (there are a couple links to the study in this thread too. I think Lily might of posted one and I did a different one.
But what are you looking for now? The actual break down of how many mechanical/tissue they give each year? and total number of surgeries? IF so I know I posted the info before, its from the annual report. I probably can't find when I posted it here before with the search funtion, but if that is what you are loooking for , I can find it again, I have it book marked
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ALCapshaw2
Well-known member
Lynlw;465099But what are you looking for now? The actual break down of how many mechanical/tissue they give each year? and total number of surgeries? IF so I know I posted the info before said:
Al
The Cleveland Clinic ratio of Tissue to Mechanical valves can be found at.
http://my.clevelandclinic.org/heart/about/outcomes/valve_disease.aspx
Click on the link in page
View or print a copy of the Valve Disease outcomes
Page 4 of PDF lists detail.
I hope this helps
The Cleveland Clinic ratio of Tissue to Mechanical valves can be found at.
http://my.clevelandclinic.org/heart/about/outcomes/valve_disease.aspx
Click on the link in page
View or print a copy of the Valve Disease outcomes
Page 4 of PDF lists detail.
I hope this helps
Almost every leading surgeons/centers usually have a relationship with the manufactures/developers of the different valves and other parts they use in the OR or afterward. They usually know what they don't like about something, and how they think it could be improved ect.
Anyway as EMU said CCF uses 85% tissue (usually bovine perimount) but you probably want more numbers and PDFs take forever to down load so for 2009 http://my.clevelandclinic.org/Documents/heart/OutcomePDFs/25_Valve_Disease.pdf (they have a pdf for all their heart vascular stats, but this section is just valves so much shorter.
Cleveland Clinic continues to perform the largest number of valve surgeries in the United States. In 2009, Cleveland Clinic surgeons performed 2,677
valve surgeries, including 1,981 primary operations and 696 reoperations
Cleveland Clinic performs the largest volume of aortic valve operations in the nation.
In 2009, we performed 1,613 aortic valve operations. Ninety-one percent were valve replacements (N = 1,468), five percent were valve repairs (N = 81) and four percent were valve-sparing operations (N = 64).
Cleveland Clinic is the leading center in the United States for mitral valve surgery. In 2009, we performed 1,332 mitral valve surgeries. A total of 70 percent were valve repairs (N = 935), and valve replacements (N = 397) accounted for 30 percent of our total volume.
Then as EMU shared In 2009, bioprostheses (biologic tissue valves) accounted for 85 percent of all valve replacement procedures at Cleveland Clinic. Bioprostheses are the prostheses of choice for most aortic and mitral valve replacement procedures.
and next to this is a little graph showing how many of each type of valve (just tissue,mech , human not brand)
and Tissue is slightly over 1500 mech looks about between 200-300 and Human less than a 100 (the graph is 500 for each line so hard to guess exactly)
so if it helps to know more exactly in 2008 http://my.clevelandclinic.org/Documents/heart/2008_Heart_and_Vascular_Outcomes.pdf starting about page 27 In 2008, 1,234 bioprosthetic valves, 190 mechanical valves and 66 allograft valves were used.
In 2008,
Cleveland Clinic surgeons performed 2,355 valve surgeries, including 1,737 primary operations and 618 reoperations.
It is interesting to remember that roughly 1/3 of their valve replacement surgeries are REDOs and most of them also get tissue valves (for example in 08 they did 618 REDOs but only used 190 mech valves.
I have looked at a few other of the larger centers to see If They had reports with as many details, but haven't found any.
and IF you get really bored here is 07 http://my.clevelandclinic.org/Documents/heart/2007_Heart_and_Vascular_Outcomes.pdf valves start at page 20 In 2007,
Cleveland Clinic surgeons performed 2,194 total valve operations, including 1,584 primary operations and 610 reoperations. about 1200 were tissue and 200 mech and less than 50 human (but it is another graph so just my estimates)
I used to have when they went from using more mechanical to more tissue, but don't see it right now. IF I find it I'll put it here.
