DocTalk Podcast: TAVR with Dr. Kaneko and Dr. Hirji

SEPTEMBER 09, 2019
Patrick Campbell
With improved outcomes and a less invasive procedure, few advances in the last several decades have been as impactful as transcatheter aortic valve replacement (TAVR) for patients with cardiovascular disease.

Beginning in the early 2000s, the approach has undergone a rapid rise in popularity as cardiologists began to see its advantages over surgical aortic valve replacement (SAVR) for the treatment of aortic stenosis. The first TAVR procedure was performed in Europe in 2002 and the first US FDA approval came in 2011.

With the recent FDA approval of 2 TAVR systems for low risk patients in August, the procedure that was once surrounded by skepticism and only considered high risk patients has become a staple.

For more perspective on TAVR, MD Magazine® spoke with Tsuyoshi Kaneko, MD, and Sameer Hirji, MD, both of Brigham and Women’s Hospital, to get firsthand perspective at how the procedure has revolutionized care.




MD Mag: Hello, everybody and welcome to the DocTalk Podcast. I'm Patrick Campbell, associate editor with MD magazine, and I will be your host for this edition of DocTalk. As we discuss TAVR with Dr. Hirji and Dr. Kaneko, of Brigham and Women's Hospital. Welcome to DocTalk. If you guys wouldn't mind introducing yourselves, telling us a little bit about your backgrounds, and listing any relevant disclosures you have before we begin, we can dive into our talk.

Hirji: Sure, my name is Dr. Samir Hirji and I am currently a surgical resident at Brigham and Women's Hospital and I am pursuing training in cardiac surgery. I'm currently doing research with a focus on transcatheter aortic valve replacement and that has been my focus on for the last 3, 4 years.

Kaneko: Okay, and my name is Tsuyoshi Kaneko. I am one of the cardiac surgeons at Brigham and Women's Hospital. I'm the surgical director of structural heart disease, and also director of clinical outcomes research in my division. And my expertise is in transcatheter therapies. After I finished my residency, I spent one year in the catheter lab. So, I sort of did the hybrid training and I've been a site PI for a lot of multiple randomized control studies involved in this field. And this is my clinical and research interest.

MD Mag: Thank you very much, doctors. Now let's get right into the questions. TAVR is really sort of an advancement that's revolutionizing treatment for patients about a decade ago undergoing a surgery like this involved, going under the knife sort of a really daunting, open procedure for patients. What advances have come about that led to this innovation? And can you take me through some of the advantages of tablet from a clinical standpoint?

Kaneko: Yeah, so you know, tab or First of all, is minimally invasive. That is definitely the most impressive portion of this procedure itself. Say, for instance, at the Brigham, we perform this procedure under conscious sedation, meaning that no general anesthesia is necessary. And oftentimes, patients directly from the cath lab, they go to the recovery room, and they do not require to go to the intensive care unit. And more impressively, about 70 to 80% of our patients leave the hospital the next day. And this is in contrary to surgical aortic valve replacement, where the day after they're still in the ICU, these patients can go home. And a lot of the people who have this disease have seen the video of Mick Jagger, who was dancing on YouTube after a week. And that is actually what you can accomplish from this procedure. It is extremely minimally invasive compared to surgery.

MD Mag: And now Dr. Hirji, if you could take me through sort of a trainee perspective, I'm not sure if you ever expected TAVR to be a part of your practice when you were first coming up through the early days of med school, but what has it been like from your perspective to learn about TAVR or and sort of the way it's revolutionized care.

Hirji: So, you are exactly correct. And you know, initially, in med school the part about TAVR because I know when I graduated, there were all these trials going on in the trans catheter space. But from a training standpoint, at this point, moving forward, TAVR sort of has to be integral and a lot of programs are making it part of the training curriculum. And that includes all the different modes of training their existing currently in cardiac surgery. The TAVR is sort of integrated as one of the trainee programs, although it is something in the works for some other programs. But I think there is opportunity for trainees to get involved really early, and then also dedicated fellowships available for trainees to do that. So at Brigham, trainees who are in their third and fourth years of cardiac surgery training, they do a dedicated year of trans catheter training. They spent a year in the cath lab, we Dr. Kanenko and the rest of the heart team, understand patient care, as well as learn catheter and wire fields. Because moving forward, catheter skills and wire fields would be very important as we adopt these newer technologies. So I think it's important from a training standpoint, for us to embrace this, learn, as well as integrate that with our traditional training.

MD Mag: Now, for those who follow the TAVR are pretty close to they're probably already aware. But for those who don't. The FDA recently approved a device from Medtronic and a device from Edward Life Sciences, tablet device for aortic stenosis for low risk heart patients. Now, this is sort of an ongoing trend that we've seen have are becoming approved for lower risk patients. Now, could you take me sort of through who qualifies for TAVR at this point? And do you think this trend of it being applied for younger lower risk generations will continue?

Kaneko: I think that is a very, very good question. And quite honestly, we really don't have an answer to at this time. As per FDA approval, the even a low risk patients, it is approved for all age groups. So, there is no age cutoff for an approval in this low risk population. Additionally, at least for Edwards Life Science, I know that by bicuspid aortic valve was not an exclusion criteria, which was one of the disease that was excluded from the original low risk trial. So the FDA sort of approved this process in a wider population than what was studied in the PARTNERS 3 trial or Evolut low risk trial. So, that is somewhat of a criticism that people are having and quite honestly, I think this approval process will lead to a lot of patients undergoing TAVR than what was initially expected. However, should we do a TAVR in a young low risk patients, I think remains a question and I think there are multiple factors that we need to think about in order to apply this new technology to younger generation. And I can go through a couple of sort of the reasons why we should be doing surgery rather than TAVR in these population. Patrick, do you want me to go ahead or do you want to ask that question separately?

MD Mag: That would be great if you could dive into that.

Kaneko: Yeah, so in my opinion, I think there's 3 major reasons to consider surgical aortic valve replacement over a TAVR. So, one is if you have a anatomical reason, that will really not get the most ideal result from TAVR. But I think these patients should probably go through surgery rather than TAVR. So, say for instance, if they have a lot of calcium and the left ventricle outflow tract, then those are the reasons why they shouldn't be undergoing TAVR, because they will be left with., number one paravalvular leak, they will have a higher chance of causing annular rupture and, you know, those issues for young patients in my mind is just not acceptable. I mean, if they go through a surgery, they can go through it with a very, very low risk. So, anatomical reason is definitely one of the reasons. So ,the second reason is if they have a concomitant operation. Say for instance, if they have complex coronary artery disease, they have aortic aneurysm, if they have mitral disease, if they have tricuspid disease that needs to be treated. You can even go further if they have atrial fibrillation, if they have taken septal that needs a myectomy — would those patients benefit from surgery rather than undergoing TAVR, and then trying to deal with other problems separately. In my mind, I think if they have concomitant conditions, they should likely undergo surgical AVR and take care of all the other problems all at once, so that they will get maximal results with just 1 operation. So that's sort of the second reason. And last, but not the least, is the complication risk. I think you have to think about what the complication risks are in these patients. Say, for instance, if they have a high risk of a stroke, you know, should those patients undergo surgery, physical AVR, they have high chance of getting a pacemaker afterwards, should those patients go for surgical AVR? If they have issues with the coronary height, you know, causing coronary obstruction should those patients get surgical AVR? I think you have to sort of balance out the complication risk between the 2 procedure and ultimately decide the adequate treatment. And again, a lot of these questions are still not answered. You know, I think there are going to be a population that will definitely benefit from surgery. And I think we're still in the process, trying to find out what that population is. And I think it's going to take the next 5-10 years to figure this out.

MD Mag: Sort of piggybacking on your responses to that last question. I've been looking through a number of studies and some of them have found a link between tapper and new onset aFib. Can you discuss this a little bit? And can you discuss some of the other adverse reactions that we've seen to TAVR?

Kaneko: Yeah, so you know, the aFib after procedure is one of the most commonly described complication. But when you look at the PARTNERS 3 trial and EVOLUT low risk trial, one of the benefits of TAVR that they had over a surgery was the risk of post procedure atrial fibrillation. So, post procedural aFib after surgery, you've seen it about 30% of the patients, whereas in TAVR it's single digit. So yes, it is a post-op complications that you can see but when you compare to surgery, it is one of the area that has to benefit over over surgery. On the other hand, though, some of the things that they saw a little more frequently than in surgery, number 2 in the EVOLUT low risk trial, was that there was much much higher risk of pacemaker requirement. So in that trial, there was about 17% risk of post procedural pacemaker implantation, whereas surgery, it was in single digits, it was about 6 to 7%. So if you use Medtronic tower valve, they had higher chance of requiring a pacemaker post procedurally. Another risk factor is vascular complication. In the past, the vascular complication has been much, much higher with TAVR compared to surgery. So that is one of the complications that you see much more frequently.

The other thing that we always get concerned about his risk of stroke. In original PARTNERS trial TAVR had higher stroke rate compared to surgery. But the subsequent trial has not shown it. And in the most recent trial, the PARTNERS 3 and EVOLUT trial, they had a trend towards lower risk of stroke with TAVR. I think the stroke was probably the most fearful complication, but we're seeing less and less of that, for sure. Last, but not the least, is the paravalvular leak, the risk of paravalvular leak is definitely higher with surgery, when you include the mild paravalvular leak, when you look at moderate paravalvular leak, which is considered to be more of a significant factor, then the incidence is still higher with TAVR, but the incidence has decreased significantly over time with the reiteration of devices. So it's gotten a lot better. But there are some certain areas that TAVR is not doing as well, compared to surgical AVR.

MD Mag: Now this one's a bit of a loaded question. But I'm right now and sort of looking forward. Where do you think TAVR will rank? Among the advancements we've seen in cardiology in the past couple of decades in terms of impact?

Kaneko: I think definitely, it's been a milestone and probably a paradigm shift. emphasized earlier, that TAVR is game changing for a lot of patients who were otherwise ineligible for surgery, or are denied surgery for being too high risk. So I think from that standpoint, and how much impact it does, in terms of access to more patients, I think it's a pretty huge milestone. And also recent studies and all these trials have been consistently showing similar result. So, thats both reassuring the fact that this is the technology that's available, and probably have more impact. Like he said we still neeed to understand important patient selection issues, and understanding who's eligible and not in some of the procedures.

And I echo Sameer's, some years opinion, and I think a lot of people are using TAVR as a disruptive technology in our field. That has happened over the past 10-20 years. And, you know, to answer your question, I think it's going to be ranked really high up there, if not, number one. So it really has a significant impact. There were a lot of non believers in the beginning. But I think now people are buying in, there's, there's no question about this.

MD Mag: Okay, fantastic. Thank you very much. And now I'll just give you both an opportunity if there was any topics or any sort of aspects of TAVR that you wanted to touch on that I didn't ask about now is your time to speak.

Hirji: So, I just had one thing that I wanted to emphasize as well, and I think we alluded earlier is that as we adopt these technologies, I think the role of a heart team as a multidisciplinary team is essential for improving outcomes. As implied, patient selection is integral to improving outcomes and for patients undergoing TAVR. So right now, a lot of programs have a heart team very involved with interventional cardiologists, as well as a cardiac surgeon. And together, they work hand in hand during the procedure, as it's required by Medicare and at the same time they see those patients in evaluate to for your candidates. So, I think moving forward, as we embrace this technology, I think we should continue to emphasize the role of a heart team in improving patient selection.

Kaneko: So I will add one thing, you know, I think there's a lot of hype about this technology. And we're really, really excited that we can actually provide this minimally invasive treatment to the population that really needs it. And for 55 year olds that are working, in their prime, that does not want to miss their work. I mean, this, this is a game changer. I mean, you know, they can go back to work in a week. And it's going to save a lot of resources for the society as well. However, on the other hand, I think we have to be cautious when we apply these new technologies, and trying to install it into a larger population. I think, initially, we're going to go all the way and try to install this on almost everybody. But as I mentioned, I think this technology is not for everybody. And, you know, as a society and a community, we sort of have to be vigilant about assessing whether these technologies in certain population is going to benefit them. And we sort of have to look at this critically. And again, like I mentioned over the next 5, 10 years will be the time to figure out which population will benefit more from surgery rather than TAVR. I mean, the paradigm has shifted, we're going to think about TAVR, but still, I think surgical AVR will have a place in the treatment of severe aortic stenosis. And I think all the people in the society and the community has to understand that and we have to do what's right for the patient at the end of the day.

MD Mag: That's it for this edition of DocTalk for the latest on TAVR and other cardiology head to MDMag.com. Thanks for listening.

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