lower tissue-valve life with higher activity level

[ctyguy]

The question came up in another thread and I wanted to get the opinions of others and to see if anyone had links to any studies or white papers that may be of relevance.

The question is, does a higher activity level (i.e. elevated heart rate) have an impact on the life of a tissue valve. Its my understanding that there is a definite link, the harder you push your heart with a tissue valve the sooner it will potentially need replacement. As we get older our heart rate slows and that is why tissue valves are generally used in older patients, they won't be as active as a result the valve will last longer.

Thoughts ?

 

[ChouDoufu]

[disclaimer: this poster doesn't know jack.]

i'd like to know, too. i've got four months to decide, going back and forth
between plastic and meat. i'd like to return to marathon running, and long-distance
bicycle touring, not sure how these activities will affect meat valve longevity.

the best simple explanation i've found so far is that meat valves deteriorate faster in
younger patients (under 65-ish) for two reasons.

1. more active lifestyle = higher heart rate = more wear and tear, so basic mechanical
breakdown.
2. younger bodies have a different chemistry which changes with age. before a certain
age, there's more calcium deposition = more calcification of valves, so chemical
degradation as well.

if this is incorrect, someone please correct me!

problem is, there's no way to know how long the current valves will last until they've
lasted. if the study finds brand X has lasted on average 15 years, then the study is
based on 1990 valves. what's the longevity of valves produced with 2008
technology?

and how to apply the study results to your particular situation. reports rarely have
a detailed breakdown of the study population, mainly just age separated into a few
brackets. no accounting (as far as i can tell) for lifestyle, activity level, other
health problems, etc. probably there somewhere, but....

 

[Susan BAV]

If you do some advance searches in the Valve Selection forum, you will find some studies posted and/or referenced in regard to chemistry and calcification, etc. I also think I recall reading something in regard to tissue valves about increasing Vitamin K intake for longer lifespan?

My cardio told me that a big issue in regard to early demise of tissue valves was oral hygiene, it being very important to keep your teeth and gums in a healthy condition.

I had thought higher HR would make a difference; but if I understand correctly, it's not a big issue.

I'm sure someone will come along and slap a study down and correct this if necessary.

We all want correct information.

 

[Duff Man]

i'm curious to know if resting heart rate has anything to do with it.

 

[tprice54]

Hr

Hr

I have not found any study (nor had my doctors) regarding increased HR and tissue valves longevity. Just like there is no reason a mechanical cannot function at 170 beats or higher. As much as I wanted this to matter in my decision in whcih valve, in the end it was not a factor either way.

 

[MikeHeim]

I did extensive tissue valve lifespan research prior to my surgery, but was lucky enough not to have to use it as I ended up with a repair. The primary reason being that at the time I was a 28YO frequent marathoner that was not excited about Coumadin. In short, I was not able to find any evidence or study whatsoever that correlated a person's activity level to how long a tissue valve lasts. To say that a tissue valve "wears out" is about as inaccurate as calling Warfarin a "blood thinner". My understanding is that what actually happens is that the leaflets on the valve begin to calcify over time, which restricts their movement and eventually means that they do not open and close property - which is when they need to be replaced. The rate of calcification is due only to an individual's chemistry and metabolism, not their activity level or how much milk they drink. Since a person's metabolism drops as they age, the valves calcify more quickly in younger folks. It would be fantastic if there were some blood (or other) test that would help predict a tissue valve's useful life PRIOR to implantation, but to my knowledge no such test exists.

 

[Leeroy996]

This may be dumb logic but if an unfit person has a resting heart rate 20 beats higher that a person that exercises then their heart may beat up to two days more "equivalent" a week.
Expand those 20 extra beats over 10 years.

To get a lower resting heart rate doesn't require the heart rate to be elevated long each week.
And that's my dumb logic.

 

[Scooby06]

Interesting discussion

Interesting discussion

Hey all.
The eternal debate.
My recomendation is to stay active and fit, as this will help if you need a re-op for any reason.

A little primer on physiology.
Cardiac output is easy to calculate, and very relevant.
Heart rate X Stroke Volume = Cardiac output.

For young, and athletic, you likely have a lower heart rate, and a larger stroke volume. When you exercise, you get both an increase in HR and massive stroke volume. This is harder on a valve (very impressive to stress test young people with heart valves, the cardiac output can go over 20 liters per minute.)

For elderly, you don't have as good of contractility so cardiac output is heavily related to heart rate. Their cardiac output is really small by comparison. Valves don't get slammed around as much.

If you are a young marathoner etc.. then the data favors stentless or homograft valve hemodynamics (or repair, but this is less than 1% of aortic surgery.)

The key to survival in the young active age group is to avoid PPM at all costs (valve to small for metabolic needs.) This has been illustrated in many studies, most recently from Cleveland.

As far as valve degenerating faster with more activity, it would likely tie to higher cardiac output. This has not truly been proven (it's theoretical.) There are marathoners, Everest climbers, Ironman finishers etc... They push both tissue and mechanical valves as hard as humanly possible, and some fail, some don't.

 

[skeptic49]

Great post!

Great post!

The rate of calcification is due only to an individual's chemistry and metabolism, not their activity level or how much milk they drink. Since a person's metabolism drops as they age, the valves calcify more quickly in younger folks.

Thanks for your post, Mike. That's good information to know.

Best wishes,

Jim

 

[ChouDoufu]

i've read (yes, more internet stuff, maybe true, maybe not) that tearing of leaflets is
more of a problem with pork valve leaflets. edwards also makes pork valves, so
why not show a comparison of their own beef vs. pork, or their pork vs. the other
white meat? interesting they showed you the side-by-side comparison of volkswagens
and yugos, instead the the golf and polo. marketing, but disingenuous.

 

[skeptic49]

The bovine pericardial tissue is much thinner but also much tougher than the porcine valve tissue.

These are interesting observations from the Edwards tour.

In one surgery video I have watched, one of the surgeons remarked that a healty natural human valve leaflet is (should be) tissue thin. It's interesting that strength of the leaflet does not correlate directly with its thikness in the case of the tissue valves you saw at Edwards.

Jim

 

[Phyllis]

I have always been interested in this question too as Dick, although 70 at the time of his AVR, is as physically active as much younger men- tennis, boating, golf, biking and lots of climbing ladders for home repairs. As I remember from that thread (I will post it if I can find it), Bob said, "Hey, better than being a couch potato!" It is now almost 5 years and after the last echo and exam, the cardiologist said, his valve was just great and would probably carry him through just fine.

 

[Scooby06]

Marketing propaganda to patients is sad...
I work for a med device company and can tell you that what they did on the tour to you should be punishable by fines and or imprisonment though it currently is not.

If you want a peer reviewed paper or two instead of some slick marketers spin, you can PM me.

Porcine lealfets are thinner, more supple, and behave differently than pericardium...
They are both good valves, FDA approved, safe, effective, and patients should never be "marketed" to in that manner.

 

[netmiff]

to get back to the original question, I believe that the strain of pregnancy in women also "wears out" tissue valves at a faster rate than normal for similar ages with no pregnancy . I could be wrong, it is just an impression I have . . .

 

[ChouDoufu]

i contacted edwards through their website, asking specific questions regarding the
longevity of valves in younger, active patients. i noted that i had searched their
website and could not find the answers, also requesting any references to papers
that would be helpful.


their response was outsourced to india:

Hello Mr. XXX,

Thank you for contacting Edwards Lifesciences regarding the Carpentier-Edwards
Perimount Magna valve model 3000. It is the first device of its kind that combines 20
years of clinical experience with the most advanced tissues engineering technologies.
It was specifically created to optimize blood flow for the patient.

The Magna valve's unique design facilitates placement at the patient's native annulus,
and its streamlined sewing ring maximizes the valve size that can be implanted also
known as "upsizing". The valve is also treated with Edwards' proprietary XenoLogiX
tissue treatment, a unique combination of surfactants and solvents designed to
effectively remove phospholipids from the bovine pericardial tissue.

For more products information and clinical data, please visit our website
www.edwards.com

Best regards,

i don't mind the outsourcing, as i'll be outsourcing my surgery to india as well, but
at least i've selected a surgeon with over 7000 procedures. but in this case,
savika b. isn't even trying. similar to oaktree's computer help desk experience,
the customer disservice rep is paid to make the problem/customer go away.

 

[MaryC]

Not trying to get off topic but would this hold true of repairs, too? Would higher levels of exercise potentially cause a need for another surgery?

 

[Superbob]

Marketing propaganda to patients is sad...
I work for a med device company and can tell you that what they did on the tour to you should be punishable by fines and or imprisonment though it currently is not.

If you want a peer reviewed paper or two instead of some slick marketers spin, you can PM me.

Porcine lealfets are thinner, more supple, and behave differently than pericardium...
They are both good valves, FDA approved, safe, effective, and patients should never be "marketed" to in that manner.

You make a good point about marketing ethics, and a reassuring one to those of us with porcine devices.

 

[tobagotwo]

Here's my take on it, to add to the heap...

The primary killer of modern tissue valves is calcification, rather than leaflet damage. It's found throughout the literature and studies. The processes used by Medtronic to preserve the porcine leaflets have been non-damaging for a number of years. Edwards also uses a nondamaging process on their cow pericardium. These treatments greatly reduce the stress on the tissue during preservation, allowing much less structural and integral damage to the tissues in the leaflets during preparation than older valves had (like the old type porcine valve that was likely in the video you saw - they are still sold by some companies).

I have never seen a study that shows a reduction in the useful lifespan of tissue valves due to increased activity level (unless steroids were involved). There also seems to be little direct association to calcium intake (although there is probably a reasonable limit to this that people are very unlikely to reach): the calcification rate seems to depend on how you metabolize it and how quick your body is to deposit it.

Young people anabolize (construct) apatite (calcium-phosphorus) compounds at a very high rate. Bones and teeth are made of, strengthened, and repaired with these minerals at a much accelerated pace in younger people. An example might be Osgood-Schlatter's disease, which is mostly limited to 10-14-year-old children. Under stress from overambitious dance classes or athletics, their tibias (a leg bone) grow bumpy overlayers of bony calcification to compensate for damage from the tendon pulling on the tibia too hard. Young people also calcify certain damaged valve material much faster than an older person. This is what makes age such a factor in a biological valve's demise, not the activity level.

Similarly, a woman who is pregnant is a calcium-metabolizing machine in maniac-level high gear, passing calcium and phosphorus to the baby for bones and teeth, and afterwards processing these minerals as major components of mother's milk. While there is certainly some extra stess on the heart, it's the calcification that chews up a pregnant woman's valve years earlier than a woman's of similar age who doesn't become pregnant. Reports of replaced tissue valves are replete with descriptions that repetitively include high levels of calcification.

The forces on the leaflets are less than we imagine when the valve is in a non-mineralized state. The pressure is mostly on the muscle tissue of the heart. The leaflets are closed by the suction and sweep of the blood coming back toward them from the aorta when the ventricle begins to open after the heart stops its squeeze, and they were engineered by the Maker in such a way that they support the pressure due to their shape, not their burst or rip strength.

Best wishes,

 

[brd]

I saw my surgeon today for my post-op visit and asked him this exact question. His answer was that it is the individual body's chemistry and metabolism and not activity level that effect the longevity of the valve. He encouraged me to continue to take the calcium supplements I have been taking to prevent osteoporosis. Barbara

 

[Duff Man]

I personally think the companies should be involved in some capacity with the patients in discussion forums. This is the leading forum on valve replacement, so I can't see why a leading manufacturer shouldn't be involved - so long as the manufacturer remains objective.

When I asked you a question in a PM scooby, you wowed me with a mini thesis on pulmonary valves. Citations and everything. You're alright man, just keep it neutral. I think anonymity is important for you, so that you can feel safe to give advice you normally would be held responsible for... if that makes any sense. For example, when I post about someone's situation, the last thing I want is for someone to sue me for thinking I'm an authority on the subject, when really i'm just doing my best to help. Information is crucial to beating this disease and you've got alot of it.