Percutaneous treatment of mitral regurgitation

Just as percutaneous therapy for coronary artery disease has revolutionised the management of patients with atherosclerosis and offered an alternative to traditional surgical management, percutaneous treatments are now becoming established for valvular heart disease. While percutaneous aortic valves are becoming increasingly common-place, treatment options for mitral regurgitant disease remain limited. One such option in development is the MitraClip (Abbot Vascular) which, via a trans-septal approach, grasps and approximates the edges of the mitral leaflets at the origin of the regurgitant jet, reducing its severity.

In the industry-sponsored EVEREST II trial, 279 patients with moderately severe or severe (grade 3+ or 4+) mitral regurgitation were randomly assigned in a 2:1 ratio to undergo either percutaneous MitraClip implantation or conventional surgical repair/replacement. The primary composite end point was freedom from death, surgery for mitral-valve dysfunction, and from grade 3+ or 4+ mitral regurgitation at 12 months. The primary safety end point was a composite of major adverse events within 30 days.

The study failed to show equipoise, with rates of the primary end point of 55% in the clip group and 73% in the surgery group (p=0.007). This difference was driven primarily by the need for …