Tricuspid valve regurgitation diagnosis and treatment methods have improved recently. Tricuspid valve insufficiency happens after heart attacks, in heart failure, in pulmonary artery hypertension. Tricuspid valve regurgitation also happens often in elderly patients. You are a leading surgeon in mitral valve and in tricuspid valve repair with open heart surgery and endovascular techniques. What are the different treatment options today for tricuspid valve disease treatment?
Tricuspid valve disease treatment has a large number of potential options. Obviously, starting with open-heart surgery, we can treat almost every patient minimally invasively. Surgery can be done both if the patient has been previously operated on or not. I think almost every high-volume center will offer a less invasive approach. It is usually done on a beating heart with a small incision. And you can replace or repair the tricuspid valve. In tricuspid valve replacement, it is always difficult to choose between bioprosthesis and mechanical prosthesis because the risk of thrombosis on the right side is always a bit higher. There is also another problem with the implantation of tricuspid valves. You are limited in case you also need to implant a pacemaker. So let's say the gold standard remains tricuspid valve annuloplasty and tricuspid valve repair. But we know that there are some patients who are not responding to tricuspid valve annuloplasty because of the geometrical changes of the right ventricle. So in these patients, we need to go for tricuspid valve replacement.
In terms of repair, almost 90% of patients are treated just by annuloplasty. A small percentage of patients receive more treatment than annuloplasty. This can be an edge-to-edge tricuspid valve repair. It is called the clover technique. Another method is leaflet augmentation. These are the two most commonly used techniques of tricuspid valve repair, in addition to annuloplasty. But I would say that on many occasions, if the surgeon predicts no effect from tricuspid valve annuloplasty, then it is a low threshold to go for tricuspid valve replacement. Now when we go into transcatheter treatment methods of tricuspid valve prolapse, then we have a huge number of options.
Most of these options are still in the early stage of the research status. There are very few CE-marked procedures. Namely, we have transcatheter edge-to-edge with MitraClip and Pascal. And we have annuloplasty with Cardioband. That's it. This is what we have. There is also a [??] line, but it's not anymore available in practice. The rest of the tricuspid transcatheter repair methods are available only as part of a research project. We have done several tricuspid valve replacements. We can make different annuloplasty approaches. We have also done out-of-the-box procedures for the tricuspid valve prolapse. There are, I think, more than 30 different devices available for tricuspid valve prolapse treatment. And none of them really reached the numbers needed to get a CE mark approval. On the other side, none has become a real alternative to edge-to-edge tricuspid valve repair and annuloplasty, which are now available for tricuspid valve prolapse. So that means a lot. It means that tricuspid valve prolapse remains a challenging procedure. It is highly dependent on diagnostic imaging, and that all these solutions are difficult to be adapted to the different subcategories of tricuspid valve prolapse disease.
So again, if you have an atherogenic tricuspid regurgitation with less tethering, you may think about implanting annuloplasty. Tricuspid regurgitation in the setting of atherogenic tricuspid regurgitation can be treated with annuloplasty. But effectively, if it is a secondary tricuspid regurgitation to pulmonary hypertension, annuloplasty may not work because leaflets are fatter. So in these cases, you need to think about the edge-to-edge tricuspid valve repair or a combination of edge-to-edge repair plus annuloplasty. Or we need to think directly about tricuspid valve replacement. But then, in tricuspid valve replacement, you need to get to the question of afterload mismatch. So it's very complicated decision-making in tricuspid valve prolapse treatment. We established already almost one year ago the working group on tricuspid valve treatment. I lead this working group together with Dr. Fabien Praz from Bern. The working group is called the PCR Tricuspid focus group. It includes about 70 experts, mostly from Europe. We also have some United States-based colleagues. We meet pretty often to discuss all these aspects and to try to understand what is the best solution for each category of tricuspid valve disease. What to do, how to select the best patients for annuloplasty, for edge-to-edge tricuspid valve repair, and for replacement of the tricuspid valve. And still, we are learning. It will take another few years before this technology will be widely available, safe enough, and performed in every hospital in the world.
So patient selection clearly is very important for tricuspid valve repair or replacement either by open surgery or by transcatheter methods. So what are the broad categories of patients for tricuspid valve treatment? What helps you to select the appropriate procedure for the appropriate patient?
We think it is very easy. Let's make it. So it's a complicated question, but we make it very easy. There are two conditions that create a leaky valve. Either it's the annulus that is dilated, so the leaflets are pulled away. Or it is a ventricle that is dilated, and the leaflets of the valve are pulled down. The combination of the two features drives the decision on treatment selection. In the case of annular dilatation, annuloplasty is the best solution. In the case of tricuspid valve leaflet tethering, annuloplasty will not work. So you need to think about either transcatheter edge-to-edge repair or tricuspid valve replacement. And this applies to surgical operations as well. If you have valvular leaflet tethering, you will replace the tricuspid valve. If the tricuspid valve is not tethered, you can put the annuloplasty ring, and usually it works.