Howard Herrmann, MD, director of interventional cardiology at Penn Medicine, reviews mitral valve replacement vs. repair, current replacement options, and new clinical trial devices.
Related Links: Dr. Herrmann's physician profile
thank you very much. It's a pleasure to share with you an overview of trans catheter mitral valve replacement. Um here at penn. These are my disclosures. So why do we need trans catheter metro replacement as opposed to either surgical repair or more likely trans catheter repair? Well one of the reasons is that there will be fewer an atomic and clinical exclusions right now when we do micro clip, what's called trans catheter edge to edge repair or tear, there are many patients who have an ideal anatomy. But as many patients, if not more who have either an unsuitable anatomy or a difficult anatomy where we might not be able to get a good result with mitral valve with mitral clip or current or similar devices. And in fact in the coop trial of functional M. R. In which patients were considered for mitral clip repair. More than half the patients were excluded for one of these reasons. The second reason to consider replacement over repair is that there will be better M. R. Reduction residual mitral regurgitation occurred in 17% of the Metro fr patients treated with micro clip in terms of severe M. R. At 12 months and even in co op which had the great results in terms of heart failure and mortality reduction. Almost a third had moderate or more mitral regurgitation residually at 12 months and even moderate FmR. Seems to affect survival and finally it works. The early data showed higher safety concerns but it's getting better. We have data from valve and valve that it works and the safety is improving hear from the TVT registry. You can see that trans catheter edge repair has been growing with a bump here when functional M. R. Was approved as a therapy based on the co op data. And now approximately 15,000 patients are treated annually with micro clip in the US. But trans catheter micro valve replacement has remained a relatively low incidents procedure. Only about 400 patients treated. Um I mean 400 sites utilizing this procedure and only about 1600 patients treated in the us. But most of these are valve and valve procedures utilizing the balloon expandable valve in a prior surgical prosthesis. What I'm here to talk about today is dedicated trans catheter mitral valve replacement in native mitral valves. And there are a number of companies doing this now. Um lots of different devices um that tells you that probably none of them worked perfectly. But we've had the experience with several of these and I want to share some of that with you. The first device that I want to mention is one that we're not yet using called the tendon prosthesis. And although when this was first proposed, a lot of us thought this might not be the way that we would be moving forward. It is a trans typical device with a tether that holds it in place at the left ventricular apex and it didn't look like it would be a very easy procedure or one that we would I think would be very good for patients. But the best results so far have been with this device and they've had excellent results. They published on the 1st 100 but more than 200 have been presented with a very high implant success rate, very low mortality and excellent reduction in Mitral regurgitation. And in fact 98% had no residual mitral regurgitation. And this is a device that first achieved ce mark approval in Europe and is undergoing a randomized trial in the us and may very well be the first device approved for therapy in the us based on the summit pivotal trial that said trans a pickle procedures are clearly more invasive than trans septal procedures. And it is expected that eventually trans septal delivery will enable better procedures in terms of safety and outcome less invasive. And that these eventually transsexual procedures will replace this trans a pickle device and we've had experience um in several trials of trans septal systems and I want to mention just two of those briefly. One is the high life system that you see here. This is an interesting device that essentially places a ring first around the mitral leaflets at the sub granular level through the aortic valve. And then once that ring is in place, a trans septal about prosthesis is delivered into the ring and is anchored in the ring and utilizes the leaflets to help prevent para valvular leak. As you see in this example here. This is the system that we are part of the investigational trial for and are accepting patients. The results so far in the 1st 20 patients treated at other institutions have demonstrated a relatively low mortality and a major complication rate and a marked improvement in Mitral regurgitation to none or trace or mild in all of the patients who have been treated. The second device that we have a little more experience with is evoke which you see here. This is a device that is also inserted transept early. It has left ventricular anchors that are utilized to grab the leaflets and then a skirt system to help seal and minimize para valvular leak. This utilizes bovine pericardial leaflets. It has a steering system that allows us to go transept really centered in the micro valve open it slowly position it in the leaflets utilizing trans esophageal imaging that has been headed by frank Silvestri and his team with Tiffany Chen here at Penn and The results have been reported now in Jack and demonstrated excellent results in terms of Micro Regurgitation Grade II only to trace to none or mild in 100% of patients with marked improvement in New York Heart Association functional class. The most recent iteration of this device is called evoke videos. You see that here it's got a shorter frame, some uh atrial shoulders to help anchor it in position um and similar in terms of how it's inserted but most importantly it has reposition, herbal and retrieval capability until it's finally released which allows for at least a lower heart rate for me. When I try to put these devices in patients, we are studying this as part of an early feasibility trial in the U. S. Um And a number of patients have now been successfully treated. This is an example of a patient treated with the evoke system here at penn and you can see the large improvement in micro valve area um that has now been stable over six months in this particular patient. In terms of a comparison of the entry criteria for those of you who are thinking of referring a patient to us for this experimental therapy. These are both early feasibility studies. So they are still non randomized patients do need to be considered high risk for surgery by a heart team assessment with symptomatic of your micro regurgitation. There is a limitation on ejection fraction. It must be 30% or higher and also on left ventricular end diastolic dimension um particularly for the high life system which has to be less than 70 millimeters. Much of the exclusions have to do with anatomy that will preclude device deployment or function. We do very careful ct measurements to look at annular dimensions, the degree of mac, the location of the papillary muscles and most importantly to make sure that when this valve is implanted there will not be left ventricular outflow tract obstruction and then there are a number of human dynamic consideration, co morbidity considerations that also limit uh enrollment for these trials. But we do believe that these are going to be important therapies in the future and hope you will consider sending us our patients. I believe that trans septal trans catheter mitral valve replacement will become a first line therapy for patients with secondary mitral regurgitation. As Mark Twain said, the reports of his death were greatly exaggerated. I'm here to tell you today that the reports of the death of trans catheter mitral valve replacement have also been greatly exaggerated. Thank you for your attention.
