Acute reverse annular remodeling during MitraClip® therapy predicts improved clinical outcome in heart failure patients: a 3D echocardiography study

BACKGROUND Transcatheter mitral valve repair (TMVR) has been shown to have acute effects on mitral valve geometry in patients with functional mitral regurgitation (FMR). This study investigates the impact of MitraClip® therapy-induced annular remodeling on clinical outcome and mitral regurgitation in heart failure patients. METHODS TMVR was performed successfully in 45 patients with FMR. In this study, mitral valve datasets were obtained before and directly after MitraClip® implantation using three-dimensional (3D) transesophageal echocardiography, and were analyzed offline retrospectively using dedicated 3D reconstruction software. Patients underwent clinical and echocardiographic evaluation at baseline and after 6 months. At follow-up, the patients were allocated into two groups according to their improvement in New York Heart Association (NYHA) functional class: a Low Responder group with ΔNYHA <1.5 (n = 25); and a High Responder group with ΔNYHA ≥1.5 (n = 20). RESULTS At 6-month follow-up, data analysis revealed that while mitral regurgitation was reduced significantly in both groups, only the High Responder group had experienced significant downsizing of the 3D circumference (137 ± 14 mm to 126 ± 13 mm; p < 0.01) and the anterior-to-posterior diameter (33 ± 5 mm to 29 ± 4 mm; p < 0.01) of the mitral annulus during the intervention. Furthermore, only the High Responder group with reverse annular remodeling as shown had substantial advances in quality of life (Minnesota living with heart failure questionnaire: 55 ± 10 to 34 ± 14 points; p < 0.01) and functional status (6-min walk distance: 290 ± 104 m to 462 ± 111 m; p = 0.07). CONCLUSION Our study demonstrates that instantaneous left ventricular annular remodeling during MitraClip® implantation is associated with improved clinical outcome of heart failure patients with functional mitral regurgitation. Trial registration The study was approved by the local ethics committee (Study Number 4497R, Registration ID: 2013121585). TRIAL REGISTRATION NCT02033811 Retrospectively registered January 9, 2014.