What does it mean for interventionalists to account for the possibility of a second TAVR before patients have undergone their first TAVR procedure?

Janarthanan Sathananthan, MBChB: If you go to any valve meeting today, one of the hot topics is lifetime management. We are treating younger and younger patients, and these patients are going to be in a situation where the patient outlives the valve. With any bioprosthetic valve, if you live long enough, it will degenerate and it will fail. Now, in the field, we are talking about and trying to understand the sequencing of how to do multiple procedures in patients. That was the focus for today’s sessions.

Traditionally, when evaluating patients for treatment of their aortic stenosis, we have looked at Society for Thoracic Surgeons (STS) score and surgical risk. In addition, as we move forward as a field, we will also consider patient longevity. If you take correlates from the surgical literature for treating failed surgical valves with TAVR, we could expect that TAVR valves, maybe around the 8-year mark, may start to fail, and we need to have a solution or an option in terms of how to treat that patient group.

What are some of the primary considerations when you are thinking about that first valve and you know that there probably will be a second one needed several years into the future?

Janarthanan Sathananthan, MBChB: When you put in the first TAVR valve, it should be a valve that potentially has a repeatable option in the future for the patient. Particularly if you put a TAVR in a young patient, let’s say in their 60s — if they don't have a redo TAVR option, it is potentially detrimental. Surgical explantation of transcatheter valves still needs more experience and time for us to understand it better. The anatomical considerations are basically related to how the TAVR valve influences the risk of coronary obstruction in the future. We talk about valve aspects like neoskirt height, but really it is the relationship of that neoskirt, which is basically a tube graft that is created, in relation to the coronary ostia and also to the sinotubular junction.

What about choosing a valve?

Janarthanan Sathananthan, MBChB: If you are talking about the first procedure, it is important to choose a transcatheter heart valve design that will set you up for the future. There are at least 7 or 8 different commercially available platforms around the world, and they all vary quite dramatically. That's the first point. The other point is that the implant depth of those valves can all vary as well. Unlike a surgeon that puts the valves in at the same place every time, we can deploy the transcatheter valve low or high, and now there is a tendency to deploy these valves higher and higher. Similarly, when it comes down to the second valve, you have exactly those same options. You can choose different types of valves, and you can also deploy the new transcatheter valve in different positions. So if you use a Sapien valve (Edwards Lifesciences), it is not necessary that you have to use another Sapien. In fact, I think many operators would like the idea of putting an Evolut valve (Medtronic) inside a Sapien. Because we have learned from surgical valve failure in terms of valve-in-valve TAVR that there are lower gradients using a supra-annular platform, so mixing and matching of different platforms is certainly possible. We don't understand at all, as a field, which is the best approach. Currently, at least, for each patient, it is going to be very individualized in terms of case planning and also for the procedure itself.

What is the advantage of implanting the valve high?

Janarthanan Sathananthan, MBChB: At the point of the very first TAVR valve, there is a general move to try and implant higher because people are trying to reduce the risk of needing a permanent pacemaker. However, by implanting higher, you are also increasing the height of the neoskirt for the future TAVRs if a redo TAVR becomes necessary. It is balancing the risk of potential coronary obstruction versus pacemaker at the first TAVR implant. There also will be differences between different platforms in regard to ease of coronary access. Already we have seen in published data that there are differences between Evolut and Sapien, for example.

Would a bicuspid aortic valve affect any aspects of lifetime planning?

Janarthanan Sathananthan, MBChB: With regards to redo TAVR and multiple valves, bicuspid valves at the time of the first procedure may influence valve expansion, maybe leak. We don't know. There are certainly data to show that. I don't know what the long term implications would be on redo TAVR. We don't understand that as yet.

What about surgical aortic valve replacement versus TAVR for second valves?

Janarthanan Sathananthan, MBChB: There are guideline recommendations on which patients should have surgery versus TAVR, but there was also data presented last year at Transcatheter Cardiovascular Therapeutics (TCT) that showed even in patients under the age of 65 in the U.S. in 2021, 50% of patients had a TAVR procedure. What many centers are experiencing is patients who are coming with the idea that they want a minimally invasive procedure, one which they can have done in a few hours and then go home the next day. That, of course, is desirable for patients, so TAVR has very much become the dominant therapy for treating severe calcific aortic stenosis, and there will be other technologies that also evolve over time. There is a lot of discussion about leaflet modification technologies and those will play a role in the future as well.

Find more: 
TVT Newsroom (With a Special Focus on TAVR)

Dr. Sathananthan presented on anatomic considerations for lifetime management of aortic stenosis patients undergoing transcatheter aortic valve replacement (TAVR) at the TVT conference on June 8, 2023, in Phoenix, Arizona. You can view his slides here.