A new device designed to combat mitral regurgitation (MR) met primary safety and efficacy endpoints in the Endovascular Valve Edge-to-Edge Repair Study (EVEREST) II, it was reported during a late-breaking data session at the American College of Cardiology 2010 scientific sessions in Atlanta, USA on 14 March.
Results of the landmark EVEREST II trial, presented by Ted Feldman, Evanston Hospital, IL, NorthShore University Health System, Evanston, USA, show that Abbott’s investigational MitraClip system may lead to fewer early adverse events than surgical repair or replacement.
After a follow-up period of one year, the MitraClip device demonstrated meaningful clinical benefits for patients with significant MR, including improvements in heart function, quality of life, and normal physical activity, and a decrease in cardiac symptoms. The EVEREST II trial is the first randomised trial of any minimally invasive mitral valve repair device compared to mitral valve surgery.
The MitraClip system includes a catheter-based device, delivered to the heart via the femoral vein. The device clips together the leaflets of the mitral valve. MR is the most common type of heart valve insufficiency and occurs when the leaflets of the mitral valve do not close completely, causing blood to flow backwards and leak into the left atrium of the heart during the cardiac cycle.
Feldman said of the EVEREST results that “the catheter-based system exhibited a highly favourable safety profile, while providing meaningful and sustained clinical benefits. The positive trial results validate our experience that the procedure is a valuable therapeutic option for select patients with MR. The therapy has the potential to transform the lives of thousands of patients, and enable some to go from bed-rest to a more active lifestyle.”
At 30 days, the MitraClip system demonstrated a superior safety profile (p<0.0001) compared to surgical repair or replacement (9.6% of MitraClip patients and 57% of surgery patients had a major adverse event). In terms of effectiveness, clinical success rate was 72.4% percent for MitraClip patients vs. 87.8%.
There were also meaningful clinical benefits in several secondary endpoints in patients with successful initial treatment, such as: reduction in the severity of MR; reduction in both the volume (left ventricular diastolic volumes) and diameter of the left ventricle heart chamber, indicating improvement in heart function; improvement in symptoms, with 97.5% percent of patients exhibiting no symptoms; and, improvements in both physical and mental quality of life compared to baseline.
“The EVEREST II safety and effectiveness results support the MitraClip device as a treatment choice, and show that MitraClip patients still have the option for successful mitral valve surgery afterward if needed,” said Donald Glower, professor of surgery, Cardiovascular and Thoracic Surgery Division, Duke University School of Medicine, Durham, USA; and co-principal investigator of the EVEREST II trial. “The improvements in symptoms, quality of life and cardiac function shown in the EVEREST II trial suggest the MitraClip procedure may be another valuable treatment option for certain patients with significant MR.”