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Melanie Cole (Melanie): Welcome. Our topic today is the INSPIRIS Valve and my guest to tell us about this is Dr. James Davies. He’s a Professor and the Director in the Division of Cardiothoracic Surgery at UAB Medicine. Dr. Davies explain a little bit about aortic valve disease and what are the hallmarks of it? Tell us a little bit also about the evolution of valve replacement and what’s different now.

James Davies, Jr., MD (Guest): So, the aortic valve is the last valve in the heart. There are four overall valves in the heart and the aortic valve is the last one before the blood ejects into the body. From aortic valve disease you can have either aortic valve stenosis or aortic valve insufficiency. Aortic valve stenosis is where the valve becomes either calcified or hardened and it doesn’t open properly. Aortic valve insufficiency is where the valve leaks. It can be either floppy and it leaks back or blood leaks back into the heart; so, either way, the valve is not functioning appropriately and they both put stress on the heart.

When you look at the hallmarks of the disease, especially aortic stenosis; without some type of surgical repair; uniformly this can be fatal. Even the data going back all the way into the 1960s, it still seems to be true today, is that without repair of severe aortic stenosis, the life expectancy can be as low as 50% at two years. Therefore, the hallmark has been aortic valve replacement.

Traditionally it is open surgical replacement done on cardiopulmonary bypass where we stop the heart and then replace the valve. More recently, we have also been doing some replacements where we do it through the groin where we actually do a transcatheter technique without stopping the heart, without opening the chest and we can replace the valve this way without ever completely stopping the heart and we are actually doing some of these procedures with patients where we can do them awake and they are not even fully put to sleep with anesthesia.

Melanie: Doctor what have been the typical valve choices when you are looking at surgical aortic valve options and you are discussing these with the patient, whether it is tissue valves or mechanical valves? What is it you have been telling them and then we are going to talk about the INSPIRUS.

Dr. Davies: So, the traditional valve choices are dividing into two main categories. One is a mechanical valve that’s made up of pyrolytic carbon material that functions as a mechanical type leaflet and one is a tissue-type valve. The mechanical leaflets can last usually almost indefinitely, but a blood thinner Coumadin has to be used for these patients. But those valves from a durability standpoint, will last indefinitely. The tissue type valves can be one of several different. They can either be porcine or pig, bovine or cow type valves. There are actually equine, or horse valves and human valves have been used. These valves have the benefit of normally not needing Coumadin or blood thinner and can be used with a less potent aspirin or aspirin and Plavix for these patients. But, depending on the age of the patients, these valves will wear out over time, just due to long-term wear and tear.

Melanie: So, then tell us about the INSPIRUS valve and how it’s a game changer for future transcatheter valve replacement and why do they call it resilient heart valves?

Dr. Davies: So, the INSPIRUS valve is a new valve that has been on the market now and has been FDA approved for about a year from the Edwards Lifesciences Corporation. Edwards is probably the main valve company for tissue valves in the setting of cardiac surgery. It’s a new valve that still uses an old platform that we have with a PERIMOUNT or the Magna Ease platform that they have that is a bovine pericardial valve but the new INSPIRUS valve has a couple of different techniques that really make it a – what we feel is a changer for long-term durability and for redo therapies in the future.

One is the Resilia treatment technique that the company has. It appears that hopefully it will make the valves last longer and less prone to deterioration. They are stating that some of these valves will last in the 15-18-year range. The data is not 100% for that because we don’t have patients out that long-term, but it appears very, very good in the early stages. We think these valves will last longer.

And the second is that the technique in the way they designed it and especially the sewing ring and the structure in the base of the valve is designed specifically to allow transcatheter aortic valve re-replacement in the future in a way that will be suitable to maximize the largest valve that can be put in at the next phase.

Melanie: That’s fascinating, and we are going to get into the valve in valve, the future prospects, but who would be the best candidates since this – since you discussed the lifetime of this particular valve. Who is the best candidate and why?

Dr. Davies: So, I think any patient in general, that has aortic stenosis or aortic insufficiency is a good candidate for the tissue-type valve. I always tell my patients that it’s a personal choice between a tissue and a mechanical valve with a lifestyle of using Coumadin versus not using Coumadin. Approximately 80-90% of all aortic valves in the country are currently tissue-type valves and so therefore, finding a tissue valve that will one, last longer and be a better option for transcatheter valve-in-valve technique in the future is the best thing we can find. So, specifically, probably optimal candidates are the younger patients, the patients that we know that are most likely going to need more than one procedure. We are trying to get them the longest time we can for the initial valve and then we are trying to make the option for the second valve be the easiest that we can to optimize the best valve we can put in the second time. So, any younger patient and by the definition of younger, I guess I would mean anywhere below 50, possibly at least below 60 years of age, but definitely patients below 50 years of age would be ideal for this type of procedure.

Melanie: So, then tell us why and how it makes it easier down the line for future percutaneous valve replacements. So, what does that mean for the patient if they are going to have to have a valve replaced in the future, that doesn’t require any open surgery, it now makes it easier, yes? Explain that a little bit for us.

Dr. Davies: So, the valves themselves like I said, will deteriorate. They become calcified and the end up having wear and tear and they will develop either recurrent aortic insufficiency or recurrent stenosis, so we have to be prepared to either one traditionally, do a redo surgery to re-replace the valve again. This puts the patient through a recurrent sternotomy or an open procedure on cardiopulmonary bypass. So, more recently in the last few years, with the advent of the transcatheter techniques; we are doing more of these by replacing these valves through the groin or to have them so that they don’t have to have recurrent open surgery on cardiopulmonary bypass. So, this allows them to have a much more minimally invasive or a less invasive technique that they can recover from quickly to have their second surgery. The Resilia valve makes this even better because the sewing ring is designed in a way that is not a complete ring initially. It’s somewhat of a partial ring that has overlap. So, when you go to replace a transcatheter valve inside this, you can actually expand the valve to expand this ring, this sewing type ring to maximize the largest sized valve that you can put in at the next stage. It’s very important because the larger the valve, the better the overall flow mechanics and the better the pressure change is for the patient so the less problems they will have with this valve long-term.

Melanie: What happens to the Resilia valve if you have to put a new valve in?

Dr. Davies: Basically, it is somewhat pushed to the side and the new transcatheter valve is set on a cobalt chromium steel cage, almost a stent-like structure that pushes the Resilia valve or the previous tissue valve to the side and then mounted and sewn on the valve itself is another bovine pericardial valve that is mounted on that cobalt chromium structure.

Melanie: That’s so cool Dr. Davies. Is there a standout case that you have been involved in? Can you tell us something interesting about doing this now and since it’s only been really FDA approved for about a year? Is there something really exciting you want to tell us?

Dr. Davies: So, there are some patients that have specifically come to us looking for this valve. Patients are more educated now with the internet and they are doing more research on their own and patients specifically. One quickly I can tell you about is a younger patient that I happen to know personally that his family are emailing and texting me recently about this type of valve. But there are other patients that I had. I had a roughly 24-25-year-old patient from one to two states over that specifically came here because they saw that we were one of first locations specifically I think the first in the south that put one of these valves in once it was FDA approved and they came here for this because he did not want to take Coumadin. He wanted to have a tissue valve. He wanted to maximize the length of the possibility of this valve and he wanted to make the best option for the second valve for his future therapies to be done. And so, he specifically sought us out for that type of valve. He did very, very well from the surgery. No issues at all and at his follow-up has been doing great. And hopefully it’s many years before we have to redo his valve, but we will be ready when he comes back.

Melanie: Then give us some predictors of treatment response. Tell us about some what you see going on in the future in this. I mean this is pretty advanced and a really exciting form of therapy. So, looking forward to the next ten years and since the studies haven’t been done for that long; what do you see is going to happen doctor?

Dr. Davies: So, the ideal therapy of what we are looking for a valve is a valve that can be placed that will last forever without having to use any anticoagulation. We are not quite there yet. We are still getting closer and closer. So, the ideal therapy is a tissue type valve that will last or some type of synthetic valve that will last the lifetime of the patient. But in the meantime, the technology between the tissue valve and the transcatheter techniques are evolving so much that the ideal situation in the next 10-15 years in my opinion, will be a tissue valve that will last 15-20 years and then another transcatheter valve that may last 15-20 more years. Now you are getting 30-40 years out of two procedures for these patients and hopefully that will extend almost all patients the life of their valve and they won’t have to have any other procedures done. So, then we can minimize the number of overall total procedures for these patients over their lifetime.

Melanie: Wrap it up for us what you would like the listeners, other providers, specifically, to take away from the fact that this is such a new technology and it’s really exciting and it’s really advancing the field of aortic valve replacement surgery so, by incorporating that expansion technology you described for us. So, wrap it up what you want them to take away from this message about the INSPIRUS valve.

Dr. Davies: So, first I’d like to make sure that everyone knows that aortic valve replacement is something we have done for quite a while. It’s very safe. The chance of having any significant complications are very low. Patients recover and do exceedingly well and feel so much better once the valve is replaced. But I’d like for them to know that the tissue-type valve that we are using expand our overall options to where patients of all ages are now candidates for these tissue-type valves. They don’t have to worry about if they have a tissue-type valve when they are in their twenties, they are going to have to have three, four or five procedures over their lifetime. I think we are rapidly approaching to where they can have one procedure in an open setting, have then one or two transcatheter techniques and hopefully may not need anything else done in the future to where the tissue-type valves will become even more and more the mainstay to where we can minimize the use of the blood thinner in these types of patients so they can be more active.

Melanie: It’s great information and thank you. What a fascinating interview this was Dr. Davies. Thank you for sharing your expertise and explaining this new exciting technology to us. A community physician can refer a patient to UAB Medicine by calling the MIST line at 1-800-UAB-MIST. That’s 1-800-822-6478. You’re listening to UAB Med Cast. For more information on resources available at UAB Medicine you can go to www.uabmedicine.org/physician, that’s www.uabmedicine.org/physician. This is Melanie Cole. Thanks so much for joining us today.