MitraClip Repair Device Showing Positive Results in Study

Results of a clinical study evaluating Abbott‘s MitraClip percutaneous mitral valve repair device have recently been announced, and the company is touting the positive outcomes. The MitraClip, which already has European approval, is designed to be percutaneously transfemorally delivered, to grasp and fasten together the mitral leaflets in patients with functional and degenerative MR. As we have previously reported, if necessary, a second MitraClip may be placed, similar to what is done in surgical E2E repair, to increase valve coaptation. All these new positive results bring hope that the device could become a standard alternative option to traditional surgical valve repairs for mitral regurg, and so may prove to be a better approach for certain types of patients.
Here are details of the results from Abbott’s news release:

In the EVEREST II trials primary safety endpoint of major adverse events (MAEs) at 30 days, the MitraClip system demonstrated a superior safety profile (p<0.0001) compared to surgical repair or replacement (9.6 percent of MitraClip patients and 57.0 percent of surgery patients had an MAE). Major adverse events is defined as a composite of 12 pre-specified adverse events. In the primary effectiveness endpoint, the MitraClip device was non-inferior to surgery at one year (clinical success rate of 72.4 percent for MitraClip patients with successful initial treatment compared to a clinical success rate of 87.8 percent for surgery patients). With 95 percent confidence, the clinical success rate of the MitraClip device falls within 25.4 percent of the clinical success rate of the surgical control. In the primary effectiveness endpoint, the clinical success rate is defined as freedom from death, surgery for valve dysfunction and moderate to severe MR (greater than 2+) at one year in patients with successful initial treatment. At one year, the MitraClip procedure demonstrated meaningful clinical benefits in the following secondary endpoints in patients with successful initial treatment:

A reduction in the severity of MR, with 81.5 percent of patients improving to mild (grade 1+) or moderate (grade 2+) MR whereas at baseline 95.6 percent of patients had moderate-to-severe (grade 3+) or severe (grade 4+) MR (p<0.0001)

A reduction in both the volume (left ventricular diastolic volumes) and the diameter of the left ventricle heart chamber (left ventricular diastolic dimensions), indicating an improvement in heart function. Left ventricular diastolic volumes decreased a significant 13 percent (p<0.0001) and left ventricular diastolic dimensions decreased a significant 6.4 percent (p<0.0001) compared to baseline.

An improvement in symptoms, with 97.5 percent of patients exhibiting no symptoms (NYHA Functional Class I) or mild symptoms (NYHA Functional Class II) [p<0.0001], whereas at baseline, 52.6 percent of patients had moderate symptoms (NYHA Functional Class III) or severe symptoms (NYHA Functional Class IV). Patients who are classified as NYHA Functional Class III or IV experience marked or severe limitations in physical activity.

Meaningful improvements in both physical and mental quality of life compared to baseline as measured by the SF-36 Survey (increase of 4.7 points in the physical quality of life score [p<0.0001] and increase of 5.8 points in the mental quality of life score [p<0.0001]).