In May, Abbott Laboratories obtained U.S. Food and Drug Administration (FDA) approval for its Tendyne transcatheter mitral valve replacement (TMVR) system to treat mitral valve disease.

The therapy can help patients whose mitral valves aren’t functioning correctly due to severe mitral annular calcification (MAC), a buildup of calcium in the annulus that supports the mitral valve. This stiffens the mitral valve’s structure and can lead to regurgitation or stenosis that disrupt the heart’s ability to effectively pump blood.

The self-expanding Tendyne valve is delivered through a small chest incision, then advanced into the heart to replace the mitral valve. The valve is repositionable and retrievable during implantation, as well.

At the Transcatheter Cardiovascular Therapeutics (TCT) conference a few weeks ago, Abbott presented final results of its SUMMIT-MAC trial, which evaluated the Tendyne TMVR in patients with severe MAC.  Paul Sorajja, MD, associate director of the Banner – University Medicine Heart Institute led the trial and was the first cardiologist to use Tendyne to treat a patient with severe MAC, which affects up to 30% of older adults.

MPO spoke with Dr. Sorajja to gain more insights on Tendyne and its potential to revolutionize severe MAC treatment.

Sam Brusco: What unmet clinical need does the Tendyne TMVR system aim to resolve? How does it compare to an invasive surgical approach for severe mitral annular calcification?

Dr. Paul Sorajja: This therapy aims to resolve the clinical dilemma and vexing situation of patients with severe mitral annular calcification. These patients have very few, if any, options because their anatomy is very complex to treat from a transcatheter and surgical means with current options. The calcification at the time of surgery is a high-risk situation because debridement can lead to severe disruption or free wall laceration; sewing into the MAC is very problematic and often associated with paravalvular regurgitation.

Thus, using a valve that could be implanted without having to manipulate or sew into the MAC is highly advantageous. Tendyne does this without the need for cardiopulmonary bypass or a traditional sternotomy.

Brusco: What did the SUMMIT-MAC trial results confirm about Tendyne?

Dr. Sorajja: The trial confirmed the effectiveness and safety of the system in patients with severe mitral annular calcification. Earlier studies had suggested this possibility with experience in compassionate use cases and early feasibility study trial experience. The SUMMIT-MAC trial is the largest experience, as well as the only pivotal trial with independent core lab adjudicated data for a dedicated TMVR device in patients with severe MAC.

Technical success was high, with nearly all patients implanted. The quality of life was significantly improved in the vast majority, with 87% of patients at one year having mild or no cardiovascular symptoms.

Brusco: How steep is the learning curve for surgeons to use a TMVR device?

Dr. Sorajja: This a novel technology with a transapical approach. There is always a learning curve, but we did not see any trends for adverse events according to experience when comparing the SUMMIT-MAC (103 patients) results to the early feasibility studies of Tendyne (191 patients)—the adverse events were similar.

Surgeons and the team will need experience with transapical procedures performed in heart failure patients for the procedure to be successful, similar to heart failure programs that have experience with LVADs.

Brusco: Anything else you’d like to say about Tendyne or mitral valve surgery?

Dr. Sorajja: The results are remarkable because this is the most extreme pathology that we will see for patients with mitral disease, and for the first time, patients now have a viable option. Tendyne was approved for this condition in the U.S. based on the SUMMIT-MAC data in the summer of this year. Hundreds of patients already have been proposed for therapy!