ENCIRCLE trial transforms treatment of mitral regurgitation

David Daniels, M.D., an interventional cardiologist with Sutter West Bay Medical Group and structural heart section chief of Sutter’s Advanced Heart & Vascular Service Line, presented results of the international ENCIRCLE clinical trial at the Transcatheter Cardiovascular Therapeutics conference in San Francisco, Calif.

The findings were simultaneously published in The Lancet.

“On behalf of ENCIRCLE investigators, I’m proud to share the results of our study which will transform care for mitral regurgitation: for patients with severe mitral regurgitation who previously had no viable surgical or transcatheter option, the SAPIEN M3 system not only significantly reduced regurgitation severity but also improved heart failure symptoms and quality of life,” said Dr. Daniels.

“This is a groundbreaking step in heart and vascular medicine—giving hope and a new therapeutic option for high‑risk patients who until now were left without a definitive treatment option.”

ENCIRCLE, a multicenter pivotal study demonstrated Edwards Lifesciences’ SAPIEN M3 transcatheter mitral valve replacement (TMVR) system effectively reduced mitral regurgitation (MR) with low rates of complications and mortality.

A total of 1,171 patients were screened at 56 sites in the United States, Canada, Europe, Israel and Australia. Thirty-five percent of those screened were excluded based on anatomic eligibility criteria.

Ultimately, 299 patients with MR ≥3+ and NYHA Class ≥II who were unsuitable for surgery or commercially available transcatheter treatment options due to clinical, anatomic or technical considerations were treated. Of these, 287 patients had a SAPIEN M3 replacement valve implanted.

The primary endpoint was the composite of all-cause mortality and rehospitalization for heart failure at one year compared to a pre-specified performance goal of 45%. After one year, the composite event rate was 25.2% (95% CI: 20.6–30.6; p <0.0001). All-cause death and heart failure hospitalization rates were 13.9% and 16.7%, respectively.

Patients also showed major gains in daily functioning and quality of life. More than 95% had little-to-no valve leakage at both 30 days and one year. Nearly three-quarters had improved heart function at one year, and almost nine in ten were able to perform daily activities with fewer symptoms.

Rates of stroke, clinically significant leaflet thrombosis and hemolysis were 9.3%, 6.7% and 7.1%, respectively, at one year.

“Percutaneous transseptal TMVR had a low mortality rate while providing a significant reduction in mitral regurgitation severity and meaningful and durable improvements in functional status and quality of life,” said Dr. Daniels.

“These findings will help guide clinical practice by providing an alternative treatment option for patients who are unsuitable for conventional surgery or transcatheter edge-to-edge repair (TEER) procedures.”

With one of the largest heart and vascular clinical trials programs in the U.S. West Coast, Sutter—a leading health system providing the latest clinical advances to patients across California—is using research to help expand life-saving possibilities and deliver new solutions to address unmet clinical needs, including in patients with MR.

Minimally invasive techniques offered across Sutter’s integrated, not-for-profit system, including robotic-assisted valve repair and replacement, are revolutionizing care—extending lives, reducing hospital stays and making high-quality care more accessible across the communities it serves.

“Dr. Daniels’ leadership on a national stage shows how Sutter is redefining the future of heart and vascular care—building on more than a century of research and innovation to expand lifesaving possibilities for our patients,” said Warner Thomas, president and CEO of Sutter Health.

“Through pioneering clinical trials like ENCIRCLE, we are at the forefront of advancing critical, minimally invasive solutions for valvular heart disease, offering new hope to those who had few or no treatment options. These breakthroughs reflect our commitment to clinical excellence powered by cutting-edge science.”