First report of US commercial data for transcatheter mitral valve repair system shows favorable outcomes

SAN DIEGO — In the first report of United States commercial experience with transcatheter mitral valve repair presented at American College of Cardiology Scientific Sessions, the system was associated with favorable outcomes and low rates of adverse events.

Perspective from James Slater, MD, FACC

The transcatheter mitral valve repair system (MitraClip, Abbott Vascular) was approved by the FDA in October 2013. Researchers analyzed the commercial experience with transcatheter mitral valve repair in the U.S. since its approval. The study included 564 patients (mean age, 83 years; 56% men) enrolled in the Society of Thoracic Surgeons/ACC Transcatheter Valve Therapy registry who received transcatheter mitral valve repair through Aug. 31, 2014. All patients had high rates of HF and other comorbidities and were considered at prohibitive surgical risk, Paul Sorajja, MD, director of the Center for Valve and Structural Heart Disease at Minneapolis Heart Institute, said during a press conference.

Paul Sorajja

Sorajja and colleagues assessed procedure success, defined as post-implant mitral regurgitation (MR) grade ≤ 2 without CV surgery or in-hospital mortality; procedure complications, including cardiac perforation, major bleeding, stroke, MI, mitral injury or death; and device-related adverse events.

At baseline, almost all patients had MR grade of 3 or 4, but after implantation 93% had MR grade ≤ 2 and 63.7% had MR grade ≤ 1 (P < .001), Sorajja said.

Procedure success was 91.8%, the complication rate was 7.8%, the average length of stay was 3 days and the rate of discharge to home was 81.9%, according to the researchers.

The rate of in-hospital mortality was 2.3% and at 30 days was 5.8%. Rates of other adverse outcomes were:

Cardiac surgery, 0.5%;
Stroke, 1.8%;
MI, 0%;
Major bleeding, 3.9%;
Cardiac perforation, 0.7%; and
Device-related events, 2.7%.

Predictors for post-implant MR grade ≤ 2 included end-diastolic diameter (P = .03), baseline MR (P = .03), clip site (P = .01) and case volume (P = .01), Sorajja said.

“Patients who had larger hearts and more severe [mitral regurgitation] at baseline tended to do not as well,” he said. “Patients who had their device implant performed at a center that was handling more cases, or if the device was placed in the middle of the valve, were positive predictors.” – by Erik Swain

Reference:

Sorajja P. Late-Breaking Clinical Trials III. Presented at: American College of Cardiology Scientific Sessions; March 14-16, 2015; San Diego.

Disclosure: Sorajja reports receiving consultant fees/honoraria from Abbott Vascular, Lake Region Medical and Medtronic and speaking for Abbott Vascular and Boston Scientific.

Perspective

James Slater, MD, FACC

This is our first look at real-world experience in the U.S. Most data that we have seen have come out of the EVEREST pivotal trial or the high-risk registry, involving smaller numbers of patients. It is a good glance at how the practice of MitraClipping is evolving in the U.S. right now.

This is a high-risk population; the median STS-PROM score for repair was almost 8%. The MitraClip is being used in the patients [in whom] the FDA intended it to be used: people who are at high risk for surgery. Data have shown that patients like this who instead have mitral valve surgery don’t do very well. Their 30-day mortality rate in a recently published meta-analysis is almost five times as high as the MitraClip group. Mitral valve surgery in these patients is a difficult path to undertake. It’s great that we have this technology more widely available in the U.S. because it makes these patients with severe MR much more functional. Almost everyone had grade 3 or 4 MR, but 93% [had] moderate or better [MR] at the end of the procedure. So it was a fairly effective treatment.

Some critics say the MitraClip doesn’t reduce MR as well as surgery. But in these mostly elderly people who are very sick with lots of comorbidities, going from severe to mild or moderate MR may be all they need to regain a certain quality of life that they were lacking. Published improvements in NYHA functional class after MitraClip support this assumption.

This real-world U.S. experience has shown the procedure to be very effective. Most of the patients who received it had degenerative MR, whereas in Europe, the MitraClip is targeted toward a population that has more functional MR. The FDA has not bought into the concept of treating functional MR with the MitraClip yet, so most operators were confining themselves to the population that the FDA intended them to be treating. There is an ongoing trial, COAPT, which is randomly assigning patients with functional MR to the MitraClip or medical therapy, so eventually we will have more data in this regard.

This is a refreshing look at the introduction of a major technology that I think has a niche application that’s valuable and is being applied across the country. I don’t know if these findings will prompt more doctors to try the procedure because it is difficult to learn. You can’t do two implants per year and expect to be very proficient. You have to be at a center where you see these patients with some frequency. Our center is doing four to five implants per month. That is enough to keep your skill set up and technically improve.

An issue that has not been discussed enough is whether hospitals are making any money on the procedure. It is woefully reimbursed right now, and it is almost impossible to get the $30,000 cost of the MitraClip back. Clipping these patients is a money-losing proposition, and that has to be fixed. It doesn’t have to be a big profit margin, but it can’t be a big hole in the budget, either. I’d like to see some progress in that regard.

James Slater, MD, FACC

Director of cardiac cath lab, NYU Langone Medical Center

Disclosures: Slater reports no relevant financial disclosures.