Monday, October 12, 2015

Decisions, decisions ...

Almost three years ago, I accidentally discovered that I have severe aortic heart valve regurgitation (leaking). The only treatment for this problem is surgery, the timing of which is somewhat controversial because we lack the highest quality evidence - multiple randomized controlled rials - addressing that question. Nevertheless, there is reasonable evidence suggesting that the time to operate was not then, and I have been grateful for the three pretty normal years that followed. Unfortunately, it appears that that time has come now.

My left ventricle has shown subtle signs of ongoing dilatation on serial cardiac MRI examinations and that volumetric increase was quite clear on my most recent images. Delaying operation has some benefits that seem largely static with the passage of time while the risk of adverse outcomes increases. The recent dilatation in my ventricle suggests that I'm probably at or near the inflection point of the curve relating the risks and benefits of waiting. It's impossible to know for sure, but I've always wanted to err on the side of operating little bit sooner rather than later if an error had to occur. Accordingly, I am going to wait no longer; my surgery is being planned for early in the new year. But no sooner is that question answered to a satisfactory degree that another question arises: what operation should I have?

The Options

Mechanical valve replacement
This option refers to surgically replacing my aortic valve with one made out of pyrolytic carbon discs that tilt open and closed. The advantage of mechanical valves is that they are very durable. There is probably an 80-90% chance that a mechanical valve will last me the rest of my life. The disadvantage of mechanical valves is that they are foreign material, and the body tends to form blood clots on foreign material exposed to the blood stream. If a blood clot formed on the tilting discs, it could prevent the discs from opening or closing properly. The valve could become severely blocked, impairing the flow of blood out of my heart, and causing a life threatening situation. Alternatively, the clot could break free and travel through just the right blood vessels leading to my brain, causing a stroke. To minimize these clot-related risks, an anticoagulant medication called warfarin is indefinitely required. Because warfarin interacts with changes in diet, liver function, and many medications, regular blood testing to determine the adequacy of anticoagulation are indefinitely required. Thankfully, I could perform these tests at home, about once a week, for the rest of my life. Despite good control of my use of warfarin, I'd probably be facing a 25% life time risk of life-threatening bleeding in the worst case scenario, or enough bleeding to require a blood transfusion in the best. So while there's probably a 75% chance of not having a major bleed, mundane human experiences like a bonk on the head, a car accident, or a bleeding ulcer could all pose serious risks to my well-being.

There are a couple of other considerations regarding mechanical valves. Firstly, they make an audible clicking sound when they close. Sometimes it's loud enough to hear in a quiet room when standing next to someone with a mechanical valve. You can check out what the click sounds like here. Some people are bothered by a sound that they can never get away from, while others get used to it and still others find it soothing or comforting. I'm not sure how I would handle the perpetual click, but I do know that if I can hear my watch ticking on my night table, I can't sleep until I put it away. Secondly, ultrasound examinations of the blood vessels of people with mechanical valves often reveal little specks flying around in the blood stream. These are thought to represent very small blood clots or bubbles, and since they are flying around all over the place, some go to the brain. There is some evidence that patients with relatively high numbers of these tiny emboli have deficits on detailed neurocognitive testing (such as memory defecits). It is unpleasant to speculate that a mechanical valve could lead to early onset dementia. Some biological valves (see below) are associated with these micro emboli, too, though they seem more common among people with mechanical valves.

Biological valve replacement
This option refers to surgically replacing my aortic valve with a new one made out of biologic material from a cow or pig heart. The tissue is treated so as to not invoke an immune rejection response. The advantage of biological valves is that they do not require anticoagulants after the first 3-6 months post-op. The major bleeding risk is therefore about half of that observed with mechanical valves. The downside of biological valves is that they wear down over time and that rate of structural deterioration is fastest in younger patients. A biological valve would be expected to last 10-15 years before requiring replacement surgery, so there is a very high chance that I'd have to have a second open heart operation to replace a biological valve in my lifetime, perhaps, even a third. While the risk of bleeding is lower over those years, the risk of the second surgery is probably double the risk of the initial surgery (though we're still talking about relatively low risks), and if a third operation is required, the risk seems to really increase significantly. Plus, each operation also carries a risk of neurocognitive decline just from being on cardiopulmonary bypass for a few hours. Open heart surgery is basically the mother of all operations, taking 8-12 weeks from which to recover. Nobody wants to have to undergo it more than once if they don't have to...

Mechanical and biological valves compared:
Both mechanical and biological prosthetic heart valves carry a similar and, thankfully, very small risk of becoming infected (endocarditis). This is a serious complication, often requiring redo surgery to remove the infected valve and replace it with a new one. At the end of the day, when these valves have been compared in people over 55, the risk over time of stroke is the same, though mechanical valves require anticoagulants for that to be the case. Survival has seemed pretty much the same, too. With a mechanical valve, the risk of bleeding is spread out over time, while with a biological valve, the risk is concentrated at those times when the valve degenerates and re-operation is required. However, there have been no randomized trials comparing mechanical and biological valves in people in their 40's, so the bottom line is that nobody can provide any confident information about how someone like me ought to expect to fare with either. All one can do is make an educated guess based on trials involving older patients and the best guess of some experts is a mechanical valve, while for others, its a biological one. (Hmmm, an interesting and important disagreement.)

Valve Repair: There is a small chance (estimated at 20-30%), that my aortic valve could be surgically repaired. This would mean that the surgeon could, if the tissues are strong and the valve leaflets long enough, artfully put in some carefully places sutures that would re-align the leaflets and make them close well again. Like a biological valve, repair would have the advantage of not requiring anticoagulants, but more importantly, it would not be associated with an increased risk of infection because no foreign material is involved. The coolest thing about a repair is that while prosthetic valves just palliate the problem, a repair could potentially cure it. The downside of a repair is that its longevity would be unknown. It could last my lifetime, but it could also fail within 2 years and require redo surgery that soon. One estimate is a 20% chance of needing a second operation at or before 10 years. The trouble with these estimates is that the cause of my valve leak isn't known; the usual conditions that cause it have been excluded. Maybe I have weak connective tissues and a repair would be destined to fail again just as my original valve did?

What am I going to do?
Well, I've made a choice, but it's not like I feel very confident about it. I remain open to new evidence and other opinions. At this moment in time, I'm planning to have a surgeon who is very experienced with aortic valve repair - and there are not that many in the world - make a judgement call in the OR: if he thinks that there is a good chance for a durable repair, that is my #1 choice. If he feels otherwise, my second choice is a mechanical valve. The On-X aortic valve has recently been shown to be as safe with less aggressive anticoagulation (INR 1.5-2 rather than 2-3) and therefore less bleeding, so I have asked my surgeon to use this valve if it comes to that.

Repair is attractive because of the lower risk of endocarditis, and because it represents a chance to be normal again. I'm willing to risk something for that, but not much. If the surgeon thinks my tissues are not up to the job of providing me with a lasting competent aortic valve, then I would prefer erring on the side of implanting a mechanical prosthesis. Why mechanical? Because while survival of patients with mechanical and biological valves has been similar in trials of older patients, my suspicion is that there will be a survival advantage in younger patients because the risk of bleeding - the major risk of a mechanical valve over biological - is lower in young patients. Plus, I'm choosing a valve that likely requires less intensive anticoagulation than has traditionally been required, and I would monitor my anticoagulation at home. All of these things should help to reduce the risk of bleeding with a mechanical valve during young years when a biological valve would be undergoing relatively rapid structural deterioration. Also, I somehow feel more comfortable taking my chances with anticoagulants, which I can to some extent control, than with watching and waiting for the clock to tick down to a second big operation. (That doesn't seem like a particularly rational consideration, but I'm with David Hume, whom I must quote at every opportunity: "Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them.")

I wish that there was an ongoing randomized controlled trial comparing mechanical and biological valves in 40 year-olds with long term follow up. I would gladly participate in such a trial and let the study make that decision for me. Unfortunately, and for reasons that are really unclear to me, no such study is underway, nor, to my knowledge, even being planned. It would seem to be so easy to do, and it's a question that's important to many thousands of people like me around the world. Too bad.

So that's likely going to be my roll of the dice. I'll probably end up with a mechanical valve and the best case scenario is that it never gets infected (95% chance), that I have no major bleeding while on warfarin (75% chance), that I get used to the click and even come to like it (? chance), and that it lasts me a long life (80-90% chance) without major neurocognitive decline (? chance). Of course, this discovery has forced me to rethink the concept of a long life: my average life expectancy is probably somewhere around 65* while it ought to be well over 70. And while it would be nice to make it to 75, doing so with cognitive dysfunction represents a particularly unattractive scenario to me. Hopefully, safer alternatives to warfarin will become available for use with mechanical valves in my lifetime.

But like I said, I'm open to other perspectives. Please share your thoughts in the comments below. Would you take a chance at valve repair? Would your back-up plan be a biological valve with a high chance of a second operation, or a mechanical valve with the life-long use of warfarin? How would you roll the dice if you were in my shoes?

*Martijn W.A. van Geldorp , W.R. Eric Jamieson , A. Pieter Kappetein , Jian Ye , Guy J. Fradet , Marinus J.C. Eijke... Patient outcome after aortic valve replacement with a mechanical or biological prosthesis: Weighing lifetime anticoagulant- related event risk against reoperation risk. The Journal of Thoracic and Cardiovascular Surgery Volume 137, Issue 4 2009 881 - 886.e5


  1. I have not had the chance to have a wiser friend than you. I am not in your shoes, but I would feel very safe, if one day I am in your shoes, to give you a shout and ask for advice. Follow your guts, because evidence you know it all. All our energy in Kingston is with your decision, and we fully support it. All the best, dear friend. AB.

    1. Thanks for the kind words and your support, my ECG-loving brother!

  2. Yorgo, Difficult decisions...
    I agree with your first choice of going for a repair. Personally I would go for a biological valve. This choice is not based on any evidence. Apart from the fact that I hat repeating noises, I would count on the progress that is being made with TAVI. I would speculate that a second open heart surgery in 10-15y would not be necessary anymore and that any possible problems could be resolved with a valve in valve percutaneous technique. Rik.

    1. Thanks, Rik. You present the most compelling argument for a bioprosthesis. If the first bioprosthesis could get me to age 55, and a valve-in-valve TAVR could get me to 65, then a second bioprosthesis at that time should last me the rest of my life. It's a very attractive idea. There should be a randomized trial!

      Interesting developments about the alleged safety of TAVRs without anticoagulation recently, though:

  3. Yorgo. You are the wisest and bravest person I know. You have thought this through meticulously and should trust your instincts on this one. As a surgeon, my feeling is that the issue of re-operation is an important one and cannot be taken lightly. I always say that our tissues are all good for one operation, and we should make that the best one. I think that if the On-x valve is associated with less need for anticoagulation, then the risk of micro emboli must be also reduced. The association between micro emboli and cognitive deficits is an association at this point, and we do not know more, if I understand you correctly. Furthermore, you know as well as anyone that maintaining 1.5 is - of not easy - at least easier and less daunting. Finally, there is the issue of myocardial damage as a tissue valve starts to decline. While the follow up would be close, there would be invariably the same weighing of options, of how long to tolerate stenosis or regurgitation while waiting for or planning a re-op, which we already know is less desirable. This would add to whatever the myocardium has already tolerated in getting to this point. Though I imagine there will be a good deal of recovery following this operation, we don't know how much. You are young. To me that means that your heart compensated for quite a bit of damage before any structural changes were observed. With the mechanical valve, it would seem you give the heart muscle the best protection for life. These are the opinions of someone not in the field, of course, but to me you are making the right call. From all of us here, to you and your family, our love, best wishes for strength and courage. We will be thinking of you all the way.

    1. Thanks, Steven. I agree about trying to get this done with one operation. There are those who argue that the mortal risk of the first AVR is < 1 % and that that risk doubles for the second operation. Still, the risk of OR#2 is going to be around 1-2%, which seems quite acceptable. But that's just mortal risk. There are other risks, not to mention the recovery and the effects of being on-pump again. At my young age, I could even be looking at a third surgery, and it's widely agreed upon that those risks climb steeply.

      I also know what it's like to live worrying from echo to echo and MRI to MRI, which I'd have to do again in the future if I went with a bioprosthesis. Sure, INR monitoring is a pain, but worrying about the next operation is one, too.

      So you're right and its nice to have my ideas bounced back at me with affirmation. It's a roll of the dice, but a pretty decent roll.

      Thanks for the love and support.

  4. Yorgo, that's a fantastic demonstration of rational decision making in valve choice incorporating evidence, preference, and probability. Do you mind if I use it (credited, of course) with patients who I'm guiding through the same process?

    High-quality aortic valve repair with a high volume surgeon isn't really an option here in Australia (as far as I'm aware) so having that option available to you -- although it complicates decision making -- is a luxury to be savoured!

    Not wanting to prompt any second-guessing, and only because you asked, I'd side with Rik on valve choice. The freestyle bioprostheses seem to do very well in the intermediate time frame. Rik's comments about the pace of TAVI improvement may prove prescient obviating further sternotomies. And at risk of minimizing the recovery process you'll be enduring, a second (+/- third) sternotomy in your 50's and 70's is nothing these days!

    I hope everything goes optimally and look forward to your post hoc analysis!

    Mike McCready

    1. Nice to hear from you, Mike!

      I'd be happy if you shared this with others going through similar considerations.

      You and Rik make a great point; it's very tempting. I really appreciate the alternative viewpoints.

      Keep well, and I'll keep you posted!

  5. I'm headed in for AVR in just over a week and I spent months agonizing over the valve selection. Initially I went into the meeting with the surgeon thinking that as a 44 year old, triathlete the Ross Procedure would possibly be a cure for my valve disease. After hearing warnings about the risks involved I couldn't justify the greater risk of complications and pita my family through that.

    After doing much research on Tissue Valves I've decided to have a bovine tissue valve put in next week. I've made that decision with the hope that I can get ten years out of the valve and data for TAVR will be solid enough that I can decide then to head in that direction or get a mechanical valve. I knew I could manage the Coumadin and deal with the noise but I couldn't commit to a lifetime valve when new technologies are showing promise. Right now there are reports out that show high degrees of complications with TAVR but when taken in context of the health of the patients it doesn't allow a complete picture. As they transition to younger, intermediate risk patients in the next few years we should have a better picture of risk factors.

    I know what you're saying about life expectancy and it's something I've thought a lot about. I have accepted the fact that this disease is probably going to limit my later years but it is what it is. All we can do is hope for the best and practice gratitude for what we have today.

    1. Best of luck with everything, Jumpy Heart. It sounds like you've thought it through carefully and made a decision that makes sense to you, and that's all that we can do right?

      One thing that may turn out to be important given your plan for future valve-in-valve TAVR is to make sure that your aortic valve annulus is generous in size so that a good size tissue valve can be put in next week. Cardiac surgeons have told me to aim for a size 23 or greater. That way, if a valve-in-valve TAVR is done down the road, the effective orifice area of the new valve, which has to fit into the old one, won't be too small.


  6. Mike and Rik,

    I wonder if you'd change your minds given this new paper from November. It's behind a paywall, but I bet that you can get your hands on it. If you do, be sure to read the editorial, too.

    Glaser N, Jackson V, Holzmann MJ, et al. Aortic valve replacement with mechanical vs biological prostheses in patients aged 50–69 years. Eur Heart J 2015; DOI:10.1093/eurheartj/ehv580.

    Medscpe reviewed it here:

    Bottom line is that in this observational population based study from Sweden, survival was considerably better for AVR patients in their 50s who received a mechanical valve, though it was not better in 60 year olds. It seems reasonable to expect that survival would be *even better* in 40 year olds, like me.

    Of course, TAVR wasn't able to have a significant impact on this cohort, so you'd still have that mystery on your side...

  7. Hi
    good post, thanks for adding this to the pool.

    to answer your question at 48 I went with a pyrolytic carbon ATS valve. Two reasons
    1 it was already my third op after a repair as a youngster and a homograft as a 28 YO
    2 I believe I can manage INR better than the literature suggests because I ho e test and self administer.

    this path is not for all, but I lo,e to have a hand in my own destiny


    1. Thanks for sharing obakesan. Your choice makes perfect sense to me. I go under the knife tomorrow and will update the blog as things progress.

  8. Hi Yorgo,

    I am 43 and due for surgery in a few days. I am agonizing over valve choice. The clicking and the warfarin have lead me to the tissue valve, but my doctor only uses the St. Jude's Trifecta GT. It has a stent, and I am told that the free standing valves are better. He is trying to push me in the mechanical direction. May I ask which valve you chose? I'm so unsure that I may cancel my scheduled surgery. Thanks, and hope this finds you well.

    1. Hi Lunacat,

      Sorry for the late response. I can certainly relate to your situation.

      I can't really comment on choice of tissue valve, and will focus more on choice between tissue and mechanical.

      I had wanted an On-X mechanical valve, but because I ended up needing a Bentall procedure, and the aortic graft composite available at Toronto General Hospital was a St. Jude product, that's what I received.

      I am not bothered by the valve clicking very much at all. If I wake up in the middle of the night, and if I lie in a certain position, I can hear it and it sometimes keeps me awake a bit longer than otherwise, but I find that if I change position, it goes away and I can fall asleep rather easily. I'm never bothered by the clicking at any other time - I'm just never aware of it.

      Life with warfarin has so far been absolutely fine. I have a home monitoring device and my time in the therapeutic range is about 90%. I have to be consistent with my leafy green intake, but so long as I am, my INRs have all pretty much been in the 2-3 range, with some minor exceptions. I think the lowest INR I ever had was 1.8 and the highest was 3.4, so no meaningful deviations form the target window. I also take low dose ASA. At our young age, bleeding is pretty unlikely, except from trauma. On the other hand, degeneration of tissue valves seems to be more rapid during younger years of life. This is the main reason why I went with a mechanical valve.

      The other issue is that at our young age, there is a good chance that a tissue valve will fail you at some point, and the timing of that is unpredictable and out of your control. I didn't like the idea of continuing to live from echo to echo, not knowing what to expect, and always worrying about when the next intervention would be. At least with a mechanical valve, I could control part of the uncertainty, which is the risk of bleeding on warfarin. By tight INR control, I think that I am lowering my risk of bleeding considerably.

      The last consideration is that with a tissue valve, you may well be looking at a third valve intervention at some point down the line. True, it may be a percutaneous procedure, but things start getting pretty complicated when they are three-dos, including valve-in-valve TAVIs.

      For me, the choice of a mechanical valve was quite clear. Its a durable solution to the problem, and so long as you don't do karate or some other activity with a high chance of trauma, and you monitor your INR closely, you should be at very low risk of bleeding, particularly during the young, good years of life.

      Regarding choice of mechanical valve, I think that they are all very good, though I would still prefer an On-X valve. They seem to be just as durable as the others, and they may well be less thrombogenic. At least they have some evidence suggesting that they are.

      Best of luck with everything, and do please let me know how things go.

  9. Hi again,

    My surgery is in four short days, and I think I am changing my mind back to mechanical. I still have so many fears about the medication, as I am intolerant to so many, but think I'll take the risk. I have wished so many times that there was such a controlled study you speak of, but know of none. I would happily let a doctor decide for me, knowing it would help others in this position. Thanks so much for sharing your decision with all of us. All the best to you.

    1. All the best to you, too, Lunacat. Please write back and let me know it all went!