Mitral valve edge-to-edge repair versus indirect mitral valve annuloplasty in atrial functional mitral regurgitation

Objectives: We aimed to compare indirect mitral annuloplasty using the Carillon Mitral Contour System and edge-to-edge repair via MitraClip in atrial functional mitral regurgitation (aFMR).

Background: In patients with left ventricular dilation, both edge-to-edge repair and indirect mitral annuloplasty are effective in reducing mitral regurgitation, while no clinical trial has compared both interventional methods in aFMR.

Methods: In a retrospective single-center analysis, 41 patients with aFMR underwent either edge-to-edge mitral valve repair (MitraClip group, n = 20) or indirect annuloplasty (Carillon group, n = 21).

Results: Both treatment groups showed high procedural success (100%) and low complication rates. Both treatment groups showed a comparable reduction of New York Heart Association (NYHA) classification postimplantation, after 3- and 12-months follow-up. Quantitative reduction in echocardiographic FMR parameters was significantly pronounced in the MitraClip group (reduction in vena contracta MitraClip vs. Carillon: postimplantation -74.6 ± 25.8 vs. -29.1 ± 17.8%, 3-months follow-up -65.8 ± 31.2 vs. -33.9 ± 17.5%, 12-months follow-up -50.8 ± 27.9 vs. -23.9 ± 17.0%, p < 0.05). Qualitative mitral valve assessment showed improved FMR class postimplantation, at 3-and 12-months follow-up in both treatment groups. Edge-to-edge repair revealed better results with lower average FMR classification compared to indirect coronary sinus-based annuloplasty. After 12-months left atrial (LA) volume was significantly reduced in the Carillon group, while in the MitraClip group no LA remodeling was found (reduction in LA volume MitraClip vs. Carillon at 12 months: +9.6 ± 25.1% vs. -12.3 ± 12.7%, p < 0.05).

Conclusions: Both indirect mitral valve annuloplasty and edge-to-edge repair are feasible and safe in patients with aFMR, while the reduction in FMR was pronounced in the edge-to-edge repair group.