Mitral repair is still a relatively youthful field at 14 years, but now operators are taking it further and developing methods for mitral valve replacement, says , of Evanston Hospital in Illinois, where mitral repair first got its start.
In this exclusive 51˶ video, the interventionist shares his insight into the limitations of the device synonymous with mitral repair, the MitraClip, and discusses the current challenges of outright percutaneous replacement of the valve.
A transcript of his remarks follows:
This is a field that has developed remarkably since the first U.S. patient was treated here in Evanston in 2003. Since then, about 50,000 patients have been treated worldwide, and that really signals the development and recognition of the effectiveness of catheter therapy for mitral regurgitation. Today that's synonymous with the MitraClip therapy, which is really the only device we have in wide use.
The impact has been to provide a treatment option for a large population of people who either have had no option at all in the past or who faced a very high-risk surgical option, which was also not always clearly effective. So we've really transformed the lives of many, many people with this therapy.
Mitral repair is a category and there are several other device therapies that have been CE mark-approved in Europe and that we're looking ahead to seeing trials in the U.S., and I think MitraClip has set the bar at a very high point for these other devices.
One of the biggest pluses that we've seen with MitraClip therapy is safety in a very high-risk population. So to the degree that any other therapy is effective, we're going to be looking for safety as well. The limitations of this device are two-fold. On the one side are technical limitations that are based on the shape and functional of the MitraClip device so that not every valve anatomy is suitable.
Most importantly in the United States it's the type of disease that affects the mitral valve. So we have U.S. FDA approval and Medicare reimbursement for degenerative mitral regurgitation, which involves abnormalities of the leaflets of the valve. There's another large group, probably larger group of patients, whose valve leaflets are anatomically normal, but have been pulled apart or malaligned due to heart failure or disease of the left ventricle or other surrounding structures. These patients we're really not as sure about the effectiveness of MitraClip.
One of the alternatives to mitral repair in which the normal leaflets are left intact is completely replacing the valve with a prosthetic device. Of course, this has been done surgically for decades, and we've seen great success with catheter replacement in the aortic valve. For the mitral valve, the story is much more complicated and the potential to replace the valve, on the one hand, is very exciting, but on the other, extremely challenging.
Probably the best illustration of the difficulty in developing mitral replacement therapy using percutaneous methods is that since the first human mitral valve replacement implant in 2012, there are still barely a hundred cases treated worldwide with a whole variety of mitral technologies. In that same kind of time-frame with aortic valve therapy, for example, we went from first implant to several thousand patients treated in just a few years.