Percutaneous mitral valve repair: the necessity to redefine secondary mitral regurgitation

Abstract

Interest in percutaneous mitral valve repair has increased during recent years. This is mainly driven by the significant number of patients being declined for mitral valve surgery because of a high risk of surgery-related complications or death. In this subset of patients, percutaneous edge-to-edge repair using the MitraClip device (Abbott, Menlo Park, CA, USA) has become an established treatment option, proven to be safe, efficient and associated with improved functional status. In contrast to primary mitral regurgitation (MR), clinical outcomes after mitral valve surgery appear to be less favourable as regards secondary MR due to heart failure. In the MITRA-FR and COAPT trials, patients with moderate to severe and severe secondary MR with reduced left ventricular function received either medical treatment (control group) or MitraClip implantation plus medical treatment (device group). Results were conflicting, with only the COAPT trial showing better clinical outcomes in the device group. However, both trials are now seen as complementary and provide useful information especially regarding patient selection for MitraClip therapy. The goal of this review is to delineate which subset of patients with secondary MR will potentially benefit from percutaneous mitral valve repair.

Keywords: Heart failure; Mitral regurgitation; Percutaneous mitral valve repair.

Fig. 1

a–c Transoesophageal echocardiogram: assessment of mitral valve eligibility for MitraClip implantation

Fig. 2

a–h Additional value of 3D mitral valve echocardiography for anatomical and morphological assessment in screening for MitraClip therapy. All patients presented with severe mitral regurgitation but are anatomically not eligible for MitraClip therapy. a Complex Barlow degeneration involving prolapse of all mitral segments. b Anterolateral commissural prolapse (arrow). c Posterior leaflet cleft (arrow). d Severe rheumatic stenosis (asterisk) with diffuse calcifications and commissural fusion (arrows). e Loss of central coaptation during systole (arrow). f A2 flail (arrow) with chordal rupture (asterisk), flail width 17 mm. g P2 flail (arrows) with chordal rupture (asterisk), flail width 22 mm. h Complex Barlow degeneration with prolapse of A2, A3, posteromedial commissure and P3 scallops (arrows)

Fig. 3

Relationship between effective regurgitant orifice area (EROA) and left ventricular end-diastolic volume (LVEDV): delineation of ‘disproportionate’ and ‘proportionate’ mitral regurgitation. LVEF left ventricular ejection fraction, RF regurgitant fraction. Adapted from [29], with permission