The Carillon device in the treatment of patients with functional mitral regurgitation

Functional mitral regurgitation (FMR), secondary to left ventricle and mitral annulus dilation, is a frequent and prognostically adverse complication of heart failure. Several different transcatheter approaches were developed as therapeutic options in high-risk patients. Among them, the Carillon® Mitral Contour System, which offers a minimally invasive, trans- coronary-venous approach to indirect annuloplasty that reduces annular dimensions and improves leaflet coaptation without the need for transseptal access or manipulation of the mitral valve apparatus. A key advantage of Carillon lies in its extracardiac, leaflet-sparing mechanism. By acting from the lumen of coronary sinus and great cardiac vein, the device preserves the possibility of future interventions such as transcatheter edge-to-edge repair, direct annuloplasty, or even valve replacement, while still allowing successful placement of left ventricular pacing leads for cardiac resynchronization therapy. The current article provides the Carillon device characteristics and technical aspects of implantation procedure. The paper is an overview of the clinical studies and real-world registries conducted on the Carillon device, and the effectiveness of this treatment for functional mitral regurgitation. We also discuss possible future perspectives of the Carillon device applications like treating patients with mild FMR, in combination with other treatment modalities, approaches or atrial form of FMR.