Clinical trial experience with the MitraClip catheter based mitral valve repair system

Severe mitral regurgitation (MR) confers a poor prognosis, in particular for patients with heart failure. Based on the results of the Euro Heart Survey, a large proportion of patients with mitral regurgitation is not referred to surgery and many other patients are rejected for cardiac surgery due to the high surgical risk or co-pathologies. Improving ventricular function with ACE inhibitors, beta-blockers and CRT may reduce mitral regurgitation, but for most patients a mechanical intervention is ultimately preferable. Mitral valve surgery is invasive and requires a long recovery period; therefore, less invasive and effective approaches are highly desirable, particularly in high risk patients. Therefore, new techniques have been recently developed to treat MR with percutaneous approach. The MitraClip device (Abbott Vascular, Menlo Park, CA) is used to treat both functional and degenerative mitral valve regurgitation. Its safety and efficacy has been initially tested in the Endovascular Valve Edge-to-Edge REpair Study (EVEREST), while MitraClip has been compared to surgery in the EVEREST II randomized trial. Besides EVEREST trials, safety and efficacy of the device as well as its health economic value is under evaluation in ongoing registries. Although the field of catheter based management of MR is at an early stage, initial clinical results have demonstrated that catheter based approaches can reduce MR, suggesting there is a great deal of potential for clinical benefit to patients with MR.