Data Shows Benefits Of Percutaneous MitraClip Device For Patients With Mitral Regurgitation
The vast majority of patients who had a successful result with the percutaneous MitraClip device did not need mitral valve surgery three years after their procedure, and many benefited from significantly improved function of the left ventricle (commonly known as reverse remodeling), according to data presented this week at the Cardiovascular Research Foundation's (CRF) nineteenth annual Transcatheter Cardiovascular Therapeutics (TCT) symposium in Washington, D.C.
During multiple sessions at TCT 2007, researchers participating in the EVEREST II study presented data from a 107-person, non-randomized patient registry. The presentations evaluated the reduction of mitral regurgitation severity with the MitraClip device and the positive impact of this reduction for patients. The ongoing randomized study arm of EVEREST II is evaluating the safety and efficacy of the MitraClip device compared to surgical mitral valve repair or replacement for the treatment of mitral regurgitation (MR; a condition in which blood leaks backward through the mitral valve with each heartbeat, causing the heart to work harder to circulate oxygen to the body). Highlights of the data presented this week include:
36 Month Follow-up Shows Ongoing Effectiveness and Durability
-- 82 percent of patients who had a successful result with the MitraClip device remain free from surgery 36 months after the procedure.
Reduction in Mitral Regurgitation Severity
-- 74 percent of patients with one or more Clips implanted experienced a reduction to less than or equal to Grade 2+ MR as assessed by the EVEREST Core Laboratory and graded per the American Society of Echocardiography guidelines.
Significant Reverse Remodeling of the Left Ventricle
-- 12 months after a successful MitraClip procedure, significant reverse remodeling of the left ventricle was demonstrated. Reverse remodeling was assessed based on five echocardiographic measures, including left ventricular end-systolic dimension.
-- In line with the reverse remodeling, 94 percent of patients who had a successful result with the MitraClip device had improved or stable New York Heart Association (NYHA) Class at 12 months following the procedure.
"Our work to reduce mitral regurgitation with a percutaneous approach continues to produce compelling results," said Ted Feldman, M.D., who presented the 36 month follow-up data at TCT. Dr. Feldman is the EVEREST II national co-principal investigator and director of the cardiac catheterization lab at Evanston Northwestern Healthcare in Evanston, Illinois. "The reduction in MR severity achieved, along with the stability of the results at 36 months and the preservation of subsequent surgical options, leads us to believe that the MitraClip device is likely to become a viable first-line option for treating MR in many patients."
Dr. Michael Rinaldi, who presented the reverse remodeling data at TCT, concurred. "The reverse remodeling data is important in that it provides compelling, objective evidence that the MitraClip device is having a positive impact on patients," said Dr. Rinaldi, director of clinical research at Sanger Clinic/Carolinas Medical Center. "Additionally, patients with the MitraClip report that they feel better and are able to engage more fully in activities they enjoy."
EVEREST Study Continues Enrollment
The EVEREST study continues at more than 35 centers in North America, with more than 300 patients enrolled and more than 300 MitraClip devices implanted to date. Investigators are currently enrolling patients in both arms of the EVEREST II study -- a randomized, controlled arm and a high risk registry arm -- with the goal of completing enrollment by the end of 2008.
"This study is gathering valuable information that cardiac surgeons and interventional cardiologists have never had before. The data provides new insights about treatment considerations for patients with significant degenerative or functional mitral regurgitation," said Dr. Feldman. "We encourage physicians to refer such patients to EVEREST investigators."
Enrollment in the study is open to a range of patients:
-- Patients with either degenerative or functional MR.
-- Patients who are good surgical candidates and are open to the option of a less invasive approach.
-- High risk patients who are not good candidates for surgery will be enrolled in the EVEREST High Risk Registry until enrollment is complete in this arm by the end of 2007.