What You Should Know About TAVR (Transcatheter Aortic Valve Replacement)
David Butzel, MD
Transcatheter Aortic Valve Replacement (TAVR) is a valuable option for patients with severe aortic stenosis who are not candidates for open-heart surgical Aortic Valve Replacement (AVR).
Severe aortic stenosis is a narrowing of the aortic valve that prevents blood from flowing through the valve freely.
This can be caused by a birth defect, radiation therapy, rheumatic fever, or age.
In TAVR, a new valve is implanted inside the patient's own narrowed valve. As a result, blood flow through the heart and body increases.
Dr. David Butzel (Guest): Okay, thanks for having me. The heart is a pump, and its main job is to accept blood that comes back from the lungs and then pump it out to the body. What’s important about this circuit is that it remains a one-way circuit. The blood only comes from the lungs then goes out to the body. In order to ensure appropriate flow, we have valves in the heart, which are basically doors, and they’re one-way doors that open and close to ensure that the blood comes through the lungs, to the heart, is accepted by the heart, and then pumped out in the correct direction. Now, there’s one major valve, which is the exit door to the heart. It has a fancy name called the aortic valve. When the aortic valve ages through time, the valve, which if you think of as a door, starts to literally rust. Hinges get rusty. And so, instead of the door opening wide to allow blood to get out from the heart to the body easily, the door starts to open less and less. When that happens, we call it aortic valve stenosis. Now, what that results in is a heart muscle that has to work particularly hard in order to squeeze blood out of it to the body, because instead of squeezing blood through a wide open valve, it’s now squeezing blood through a valve that opens just a little bit. When that happens, you get back pressure that builds up from the heart back into the lungs. As such, when people have aortic valve stenosis, they start feeling the effects of this back pressure. And that typically is experienced in either shortness of breath, which is the most common symptom, or chest pain or pressure with exertion, or sometimes even a passing out or getting close to passing out. When we evaluate patients who have severe blockage of their aortic valve and whose blocked valve is causing them to have symptoms, we know at that point that it’s time to do something to try to help them. The traditional treatment has been open heart surgery, where the old valve is cut out and a brand new valve is sewed in with direct sight. Unfortunately, there are many elderly people or people who have other illnesses that are bad candidates for open heart surgery. Because of that, a new procedure has been developed over the last 10 years, and that’s called TAVR, and it stands for transcatheter aortic valve replacement. I’d be glad to answer more questions about TAVR as we move forward here.
Melanie: That was a great lesson and very, very understandable. As I understand it, you are the first in Maine to perform TAVR. Why don’t you tell the listeners, Dr. Butzel, in your very unique way, how TAVR is, how you do this type of procedure, and what are the outcomes like for people that are considering undergoing it?
Dr. Butzel: Okay, we’ll start with once a patient has been diagnosed with severe aortic valve stenosis, they are originally evaluated by a team of physicians. There are a combination of type of cardiology doctors. There are heart surgeons on the team. There are people called interventional cardiologists who put stents in heart. There are special general cardiologists who work on studying the heart muscle and the valves. If that multidisciplinary team feels that the patient truly is not a good candidate for open heart surgery, then the patient goes through a series of tests. And that can take quite a while. Those tests involve taking pictures of the heart arteries—we call that coronary angiography. We also do a very specialized CAT scan of all the blood vessels in the chest, the abdomen, and the pelvis. We do a special type of ultrasound test, where a patient swallows a probe and we take a look at the heart valve from inside the body out. That allows us to study the intricacies of each person’s heart valve. Once we get all those tests together, we decide whether a person is a good candidate for the TAVR procedure. One of the very important things to understand from the beginning for patients is that just because you’re not a good candidate for traditional open heart surgery, it does not mean that you are automatically a good candidate for the TAVR procedure, because there are different criteria for both of those procedures. Now, if we get past that stage and we determine that a patient is appropriate to get a new valve by using the TAVR procedure, we then move forward with the procedure. The procedure involves putting a new heart valve inside the old heart valve. I’ll explain that in a minute in a little more detail. Many people’s first questions are how do you get that new valve in there? There are three ways that we deliver this new valve. One is up through an artery in the leg. The second route is directly through the front of the chest wall, where we do a small operation and put the valve in by going right through the aorta, which is the big blood vessel that comes out of the heart. The third way is to do a small operation on the side of the chest where we actually put the new valve in by making a very small hole in the actual pumping chamber of the heart itself. That’s what we call determining the appropriate vascular access. Once we’ve determined that access, we put the new valve in by smooshing that valve down inside a metal tube called the stent. That stent that has a valve that is sewn on the inside of it is positioned directly inside the old valve. What we do—and it does seem strange—is we actually inflate the stent by putting a balloon inside of it, and that stretches open the stent. It smooshes the old valve to the side, and once that stent is wide open, the new valve that is inside the stent starts to work immediately.
Melanie: Wow! That is absolutely fascinating, and what an amazing procedure that you’re doing, Dr. Butzel. We only have a few minutes left here. Tell listeners, what is the outcome? Is this valve replacement something that will last for the rest of their lives, or is it going to have to be done again?
Dr. Butzel: We don’t know exactly how long these valves last. In Europe, these valves have been put in as far back as 7 to 10 years ago and there has not been any reports of them wearing out. We are very hopeful that this valve will last forever. However, you also need to keep in mind that many of the people that qualify for this valve are quite elderly because that’s part of what makes them a bad candidate for heart surgery. Even if these valves last more than the 10- to 15-year range, that may realistically be perfectly appropriate for that patient population. In general, patients’ major complaints is of severe shortness of breath, that they just don’t have their lungs. And when we see these patients at a month follow-up, most of them say exactly that when we ask them was it worth it, what feels different now than before, they almost universally look up at us and say, “I’ve got my lungs back.” Most of them have a very dramatic improvement in the quality of their life. In general, patients are in and out of the hospital in around five days, some a little shorter, some a little longer. But overall, we’ve had a great success. We’ve treated approximately 130 patients over the last two and a half years with excellent clinical outcomes.
Melanie: And being that you are the first in Maine to perform this procedure, tell the listeners why they should come to see you when they’re considering heart valve replacement.
Dr. Butzel: Well, I think Maine Medical Center is a very unique place in terms of being able to offer this valve with a very, very high quality backing behind it. We have a multidisciplinary team that is seamless. We have heart surgeons, cardiologists. We have radiologists. We have anesthesiologists. We all work seamlessly together. We’ve been at it for two and a half years. We’ve had very, very, very good outcomes. I think, in a sense, our strength is that the team is very, very united. There are no major egos involved here. You just have people who come from lots of different camps who are very, very, very invested in bringing this new technology to the appropriate people in the safest way possible. We are a very well-coordinated group. We love working with each other. I think it shows with the patient’s experiences that they’ve had coming through our system and the results that we’ve had.
Melanie: Thank you so much, Dr. David Butzel, for that absolutely fascinating information. You’re listening to MMC Radio. For more information, you can go to mainemedicalcenter.org. That’s mainemedicalcenter.org, mmc.org. This is Melanie Cole. Thanks so much for listening and have a great day.