Societies Propose Volume, Proficiency Needs for Mitral Interventions

As experience continues to grow with transcatheter mitral valve (MV) repair and replacement, particularly edge-to-edge repair, professional societies have come together to update operator and institutional requirements for those initiating and maintaining programs.

When setting up a new program, for example, participating interventional cardiologists or cardiothoracic surgeons need to have 50 lifetime structural heart procedures under their belts, including prior experience with MV repair and at least 20 transseptal interventions (10 as primary or co-primary operator), the multisociety document stipulates. Sites have to show that they have a surgeon who has performed at least 20 MV operations in the past year or 40 in the past 2 years, with a minimum site volume of 40 surgeries in the past year or 80 in the past 2 years. At least half of all those procedures should be repairs (as opposed to replacements).

For established programs, sites need to show that they have performed at least 20 transcatheter MV interventions per year, or 40 over 2 years, with similar requirements for MV surgery. They also need to demonstrate 30-day mortality rates above the lowest decile, participate in the Adult Cardiac Surgery database of the Society of Thoracic Surgeons (STS), and maintain an STS star rating of 2 or higher for at least two consecutive reporting periods for MV replacement with and without CABG.

There are PCI requirements for sites as well, including a volume of at least 300 per year, participation in a national registry, and maintenance of in-hospital, risk-adjusted mortality above the lowest 25^th percentile.

The recommendations and requirements come from the American Association for Thoracic Surgery (AATS), the American College of Cardiology (ACC), the Society for Cardiovascular Angiography and Interventions (SCAI), and the STS, and are endorsed by the Heart Failure Society of America.

“AATS, ACC, SCAI, and STS believe that adherence to these recommendations will maximize the chances that these therapies will be successfully incorporated into management pathways for patients with MV disease in the United States,” the writing group chaired by Robert Bonow, MD (Northwestern Medicine, Chicago, IL), states. “These recommendations attempt to balance the need to support optimal quality outcomes with the goal of facilitating access to such innovative therapies—an important paradigm for the development and implementation of future, less-invasive approaches to structural heart disease.”

Emphasis on a Multidisciplinary Care, Shared Decision-making

The document, published online December 16, 2019, in the Journal of the American College of Cardiology and the journals of the respective societies involved in crafting it, updates an earlier 2014 set of recommendations. That previous iteration came out just a year after the US Food and Drug Administration initially approved the MitraClip (Abbott), which remains the only approved device in the US for transcatheter MV repair.

This update incorporates new clinical, registry, and trial experience—from COAPT and MITRA-FR, for instance—but because the evidence is still accumulating, the standards are also based on best practices and expert consensus. The document is similar in theme and context to one released for TAVR last year, Bonow et al note. “It is recognized, however, that there are significant differences not only between aortic valve and MV pathologies, but also between the respective pathways for patient evaluation, treatment options, and interventional/surgical skill sets.”

As the authors detail recommendations and requirements for operators and institutions to perform transcatheter MV interventions, the need for a multidisciplinary care team headed by co-directors representing interventional cardiology and cardiothoracic surgery remains key.

“No one individual, group, or specialty possesses all the necessary skills for optimal management of these complex patients,” the authors write. “Therefore, it is essential that the cornerstone of a program to manage patients with mitral regurgitation is a formal, collaborative multidisciplinary team with expertise in valvular heart disease, heart failure, electrophysiology, cardiac imaging, interventional cardiology, cardiac valve surgery, and cardiac anesthesia.”

Sites must have an active cardiac surgical program supported by at least two surgeons with experience in valvular disease as well as a “full range of diagnostic imaging and therapeutic facilities,” the authors state.

“By their very nature, these complex procedures should only be undertaken in institutions that routinely perform surgical MV operations and participate in the STS Adult Cardiac Surgery Database with outcomes that equal or exceed those expected for their case mix relative to national benchmarks,” they say. “Similarly, only institutions with interventional cardiology programs that have established programs in PCI, balloon valvuloplasty, TAVR, catheter closure of periprosthetic leaks, and deployment of septal closure devices, with outcomes that equal or exceed those established nationally for similar procedures, should offer transcatheter MV intervention.”

Informed shared decision-making in the context of patient- and family-centered care is emphasized, too. “This recommendation goes beyond patient education and the traditional use of informed consent, which involves an explanation of generic risks and potential benefits of any intervention,” Bonow et al explain. “It specifically includes an individualized approach utilizing patient-specific, data-driven risk assessment; clear explanation of treatment options; explanation of the rationale for the multidisciplinary team’s recommendations; and the incorporation of patient goals, preferences, and values into treatment decisions.”

Outcome Reporting, Surveillance, and Compliance

The writing group offers suggestions for outcomes measures to reflect quality and metrics to allow for the monitoring of performance. “These measures are proposed as appropriate starting points in this evolving space, in which risk-adjustment tools are not yet available,” they say.

Specific outcomes they recommend for tracking are in-hospital and 30-day all-cause mortality; stroke/TIA, major vascular complications, major bleeding, moderate-to-severe or severe mitral regurgitation (MR), and significant mitral stenosis at 30 days; and all-cause mortality, change in patient-reported health status by the Kansas City Cardiomyopathy Questionnaire, rehospitalization for heart failure, repeat MV intervention, moderate-to-severe or severe MR, or significant mitral stenosis at 1 year. The authors also list other metrics that could be considered for quality assessment.

The writing group stresses the need for ongoing participation in national registries to monitor the efficacy and safety of transcatheter MV repair and replacement systems and also for compliance with the proposed standards.

“Compliance with these professional society recommendations is voluntary but expected in order to achieve and sustain optimal care for patients with MV disease who are considered for transcatheter or surgical intervention,” the authors state.

As the field of transcatheter MV interventions continues to develop, “it is expected that the proposed requirements herein will need to evolve with further advances in equipment, techniques, and patient selection,” Bonow et al acknowledge. “Nevertheless, the guiding principles and foundational elements included in this and companion multisociety documents constitute an enduring commitment to optimizing patient outcomes.”