Transcription:

Scott Webb (Host):  Today, we’re discussing the latest in valve repair and replacement interventions. Joining me to break it all down for us is Dr. Marc Gerdisch, Chief of Cardiovascular and Thoracic Surgery and Co-Director of the Heart Valve Center and Atrial Fibrillation Program at Franciscan Health. This is the Franciscan Health Doc Pod. I’m Scott Webb. So, Doctor, thanks so much for joining me today. Let’s start with a basic one for you here. What do heart valves do? What’s their main function?

Marc Gerdisch, MD, FACS, FACC, FHRS (Guest):  Heart valves are kind of the doors that are responsible for ensuring that your blood goes in only one direction through the heart. So, they open to permit blood to flow forward and they close to keep it from going backward. And in so doing, they ensure that the blood is going in one direction all the time.

Host:  So, when we talk about valve disorders, what are some of the more common heart valve disorders?

Dr. Gerdisch:  There really are kind of two general categories and then occasionally they are actually mixed but one or the other usually dominates. And they are stenosis or insufficiency or regurgitation. In stenosis, the valve is blocked so, in a sense, when the heart squeezes and needs to push the blood along; the door doesn’t open adequately so the valve is blocked, it’s stenotic. And it’s the most common disorder that affects for example aortic valves and then leaking or insufficient valves, regurgitant valves those are valves that when the heart squeezes to push the blood in one direction; the valve doesn’t close behind the blood well and the blood goes backward, leaking, they call it in a sense, back into the previous chamber. That affects a little bit more often the mitral valve or the tricuspid valve but certainly can effect the aortic valve as well.

Host:  So Doctor, when we talk about heart valve disease, how does a valve fail?

Dr. Gerdisch:  There are multiple mechanisms and it depends on which valve. There are dominant mechanisms in people of different pathophysiologic categories and different age groups. But the fundamentals again, when we talk about a stenotic valve; the kind of uniform finding in a blocked or stenotic valve is that the valve’s leaflets which are the kind of hinged portions of the valve that move; those leaflets have become stiff and they become calcified and they can become quite bulky with calcification and rigid and don’t move. And that can happen for example in some people who are born with a bicuspid aortic valve. It happens in about 1.5% of all people on the planet. The most common cardiac congenital anomaly and in those patients, they have a predisposition to either for the valve to either become blocked or for it to develop a leak. So, a person can be born with a predisposition to a valve becoming stenotic.

On the other hand, people who have atherosclerosis, people who have comorbid conditions that increase the likelihood of having cholesterol disposition in their blood vessels. If they have that predisposition for cholesterol deposition in their blood vessels; they also have a predisposition at times for it to accumulate and to calcify in the valve leaflets. So, that can be a little bit more dependent on for example, diabetes or smoking or again genetics. Some people have genetic predispositions to developing these types of disorders. And as that occurs, the leaflets don’t move well anymore and like I said, it happens most typically in the aortic valve, which is the valve between the left ventricle, the main pumping chamber that generates your blood pressure. It’s between that and your aorta which is the main blood vessel that delivers blood out to the body.

It can happen also in the mitral valve that the mitral valve becomes blocked. That tends to be more commonly related to rheumatic fever believe it or not and we still see a fair amount of that. So, people who have rheumatic fever as a child, will develop antibodies against their own valve and over time, the valve will become thickened and not function well. There are some people, as they get quite a bit older, they can just develop calcium in the mitral valve like they would in other valves or in blood vessels and that can then lead to a valve that doesn’t open well. So, kind of the uniform finding is that the leaflets become thickened, they become calcified, they don’t move well and then the valve doesn’t open well.

For leaking valves, it’s a little bit different scenario. So, for leaking in the mitral valve, the mitral valve being the doorway between the left atrium and the left ventricle, the upper chamber and the lower chamber on the left side of the heart. That valve tends to leak, and it tends to leak due to a genetic disorder and that, it’s not an obviously heritable genetic disorder. In other words, it’s not passed down from one family member to the next in an obvious fashion, but it is clearly related to genetics and the valve is kind of set up to over time fail. And so we see that in a relatively younger age group. It can be people even in their 20s. They are usually in their 40s or 50s and those patients the leaflets start to not stay in place like they are supposed to because they start to deteriorate in certain areas and that leads to that valve leaking badly.

And then we rebuild that valve to restore it back to function. A leaking aortic valve, again is more frequently associated with people who have bicuspid aortic valves or are born with an abnormal aortic valve. It in fact has two leaflets instead of three, in a sense. That’s why it’s called bicuspid. And they do tend to leak. And they leak because the anatomy isn’t quite normal, the geometry of the root which is the very first portion of the aorta can be abnormal, and those things conspire to make the leaflets kind of droop down and then the valve leaks. And there again, we reconstruct that valve and repair it. so, I would say that there’s also a common theme in interventions.

So, when you have leaking valves, we repair them. When you have a blocked valve; then we have to replace the valve because the valve leaflets themselves have been replaced by calcium. So, those are kind of the two general categories. Leaking valves can occur in other positions as well, the tricuspid valve, the pulmonic valve and sometimes valves are not behaving normally because the heart itself has been injured. So, people who have heart attacks can develop a leaking mitral valve. People who have elevated pressure in the pulmonary artery as a consequence of lung disease or a condition we call sleep apnea; that can result in failure eventually of that tricuspid valve and leaking there. So, as you can see, there’s a lot of mechanisms and the kind of the common elements are for the stenotic valves, there is calcification and stiffening of the leaflets and for the leaking or regurgitant valves; there’s deficiency in the structure of the leaflet that leads it to leak.

Host:  Yeah, great job. You covered a lot there including risk factors and standard treatments. I wanted to get in and talk about minimally invasive treatment. Is that right for everybody? And either way, what are the types of minimally invasive treatments that you are doing for valve repair or replacement?

Dr. Gerdisch:  The spectrum of minimally invasive interventions that we now have for treating valve disease is very broad. And to some extent, they apply to every patient in the sense that we first approach everyone as a potentially minimally invasive surgery. By diminishing the destruction of the patient’s chest, by minimizing the trauma, by going through a small incision, often not touching the bone at all; that really does enhance the experience, the recovery, the cosmetics of the operation. But we always start fundamentally with the first principle which is perfect surgery. What is the absolute best that we can do for that person’s valve and heart and then recognizing that and identifying that procedure; how do we go about doing it with minimal destruction to the patient?

So, indeed, there are patients for example, higher risk, or older patients or patients with comorbid conditions that we have the now, really the luxury and they too of being able to do a valve without stopping the heart, without opening the chest, we can go through the patient’s leg usually, through the artery in the leg and replace the valve. We did one today in an 86 year old gentleman like today, that is a – it’s a small miracle. Because it really doesn’t change the stride of their life. He’ll go home tomorrow.

Moving into a little bit more invasive but still very little perturbation of the patient; the vast majority of times that we’re repairing or replacing a valve; we can do it through a small incision between the ribs without touching the sternal bone. So, we try to stay away from the sternal bone as much as we can because that’s a little bit bigger experience for the patient, it’s a little more disruptive and so the vast majority of single valve operations and many of the double valve operations we can do through a small incision between the ribs. And so, that’s basically regular old heart surgery, but we do it through a small incision and we’re able to provide the patient with a faster recovery and a better looking incision and just a nicer outcome. But always focused on perfect surgery every time.

So, sometimes, in order to do lets say three valves, or to do a reoperation for someone or to do multiple coronary bypasses and valve surgery for someone, like the lady I saw this morning; those patients we’re s till going to go through the breastbone. So, Franciscan a couple of years ago after we did a randomized controlled study which is kind of the best type of study you can do and as part of a national study; we proved that patients could recover better, faster, and more comfortably is we repaired the bone as an orthopedic procedure. So, doing it like an orthopedic surgeon would. As you can imagine, hundreds of thousands of people have heart surgery every year and their bone gets put together with some wires and it’s no orthopedic surgeon would every do that. So, now, for those patients that we cannot go through a little incision, and it’s not a lot of them, but some of them; for those patients, then we finish the operation going through the breastbone, and we use a series of titanium plates to put the bone back together and let them just go back to their lives.

So, everybody that has heart surgery with us, the day after heart surgery, can lift 15 pounds. They can use their arms to get up and down and then they go home from the hospital. So, it really has changed the experience. Whereas, we are always focused on providing the patient the least invasive operation; we’ve also sorted out mechanisms, therapies, techniques for minimizing the entire experience for them. So, over the last few years, we’ve developed the rapid recovery protocol. We have engineered a program that specifically addresses patient comfort, mobility, restoration of full activity because basically, what we want to do, is we want to take away – a patient never really feels completely whole, they don’t have their complete sense of wellbeing until they don’t have a sense of anything different about their body. So, we’ve really gotten to the point where we can get rid of the different. We have really restored people back to full activity rapidly with minimal discomfort and a much, much more expedited return to their full lives.

Host:  And Doctor, take us through the process of determining whether valve repair or replacement is the proper intervention for a patient.

Dr. Gerdisch:  Maybe when we talk about in the context of what we do for valves; maybe the most important thing that we do is decide kind of what device they are going to have, if they are going to have their valve replaced or if we are going to repair the valve. If we repair a valve; we don’t burden the patient with any of the consequences of replacing the valve. So, every time we look at a valve, we determine if it can be repaired. Extremely important in mitral valve disease and in fact, essentially every leaking mitral valve should be repaired and can be repaired through a small incision. It’s become more true now for aortic valves. So, now in the last couple of years, I’ve repaired every leaking aortic valve and that’s new. That’s a different position. That came about just in the last few years as we really refined the techniques for repairing an aortic valve. So, someone might say, well why not just replace it. the reason is, that as wonderful as the new technologies are that we have, transcatheter valves, the surgical biologic valves, the mechanical valves; all of those are in a sense a disease trade off. I take away your bad valve and I give you a better valve but every prosthetic valve, every replacement valve carries a risk of permanent risk, a small risk every year for the rest of your life of stroke.

And that doesn’t exist for your native valve. So, if I can repair, rebuild your valve; I don’t give you that added risk. And it becomes quite important in somebody let’s say who is in their 50s or 60s who might live another 20, 30 years. Those patients would really benefit from avoiding the consequences of a prosthetic valve. So, we’ve really honed in on that. It’s been a major career path for me and has always been. Now I feel like we’ve been able to transition from not just repairing all the mitral valves but now being able to repair many of the aortic valves. And that is a new thing. That is a breath of fresh air in the realm of valve intervention.

Host:  As we wrap up today Doctor, let’s talk about the latest in valve replacement technology especially tissue generated valves.

Dr. Gerdisch:  When we do replace a valve, again, we have this very exquisite technology of the transcatheter valves, and we have biologic valves that we can implant surgically; I think another important change came about when we did a study with a mechanical valve called the Onyx valve. Mechanical valves, people call them metal valves, but they’re actually built of carbon and we performed a study in which we were the primary enroller for the entire nation where we proved that with that mechanical valve; we could give the patient a lower dose of blood thinner. So, the blood thinner is there to prevent them from having clots and strokes. Fine, we proved with that valve, that we could run it at a lower dose which would also dramatically reduce their risk of bleeding related to being on the blood thinner.

Which then meant that we could give them a mechanical valve that would last the rest of their lives, never wear out whereas tissue valves including the bioprosthetic valves we implant surgically and transcatheter valves, they do wear out. We could give them a mechanical valve, a carbon valve that would last the rest of their life and that they could be on a lower dose of blood thinner. So, now the next step in that evolution is we just started enrolling in another study with that mechanical valve using a blood thinner that doesn’t require blood checks. So, the thing that people really dislike about being on warfarin or Coumadin, the blood thinner that’s typically used for mechanical – for carbon valves is that they have to check their blood level, they have to check their blood thinner. So, we’re just now starting a study with a non-coumadin blood thinner. A pill that you will just take the pill and you don’t have to check it. And you don’t have to worry about what you eat. It doesn’t – it’s not affected by your diet. So, that could be the next level really in giving somebody a valve that they don’t every have to concern themselves with again. And they just have to take the pill.

So, these are really revolutionary paths that maybe they don’t seem as glamorous, but they are spectacularly important to patient outcomes, durability, the likelihood of having one procedure, never having to go for another operation. The last thing I would ass about kind of valve technology is the devices themselves. For the past decade, I’ve been working with tissue engineered valves and generating heart tissue in human beings. And we were the first in the world to implant an extracellular matrix inside of a heart and have tissue grow back there. So, during that time, I started building valves out of material called exocellular matrix and implanting them in the right side of the heart in people who have had infected tricuspid valves. There were other surgeons around the country that were doing it and in 2014, I published the national results for that. And then eventually, we were able to develop a valve that we now take off the shelf that’s made of that material, that we now have in an FDA study of which I’m the principle investigator for the entire country. And that valve comes off the shelf, is made of that material, we implant it in the patient, and it becomes their tissue.

So, that’s the first step toward moving valve technology, replacement technology toward growing your own valve. It’s a way off, but as we move to the other valves; but it’s the first step in that direction and I hope to see by the time I finish my career that we are actually doing that for all the valves.

Host:  Yeah, I hope so too. This is just so inspirational. I mean just jaw dropping stuff and I keep coming back to something you said there a couple of times that the goal here always with patients is the perfect surgery. What’s perfect for them and it sounds like through all the work you’re doing and all that we’re looking to in the future that patients are in good hands there at Franciscan. Doctor, thanks so much for joining me today. Stay well.

To request an appointment with Dr. Gerdisch, call 317-851-2331 and to learn more about valve care visit www.franciscanhealth.org. And we hope you’ve found this podcast to be helpful and informative. This is the Franciscan Health Doc Pod. I’m Scott Webb. Thanks for listening.