Remodeling on Lateral Side of Posterior Mitral Leaflet in Recurrent Mitral Regurgitation after Mitral Annuloplasty for Patients with Atrial Functional Mitral Regurgitation

Objective. The high recurrence rate of mitral regurgitation (MR) in patients with atrial functional mitral regurgitation (AFMR) who underwent mitral annuloplasty (MAP) is reported. However, the mechanism of recurrence is not fully understood and appropriate surgical intervention remains unknown. Herein, we reviewed patients with AFMR who underwent MAP at our institution and investigated the preoperative geometric characteristics of the mitral valve in terms of MR recurrence after surgery. Methods. We retrospectively evaluated 20 patients with AFMR who underwent MAP between 2010 and 2022. The mean follow-up period was 3.2 ± 2.3 years. Preoperative three-dimensional transesophageal echocardiography (3D TEE) was available for all patients, and geometric analysis of the mitral valve was performed using the Philips Q-Lab software. Results. MR recurred in six patients. The rates of freedom from MR recurrence were 79% and 57% at one and three years, respectively. The lateral portion of the posterior mitral leaflet (PML) in patients with recurrent MR was longer and thicker than that in patients without recurrent MR (length of P1; 10 ± 3 vs. 15 ± 5 mm, p < 0.01, length of P2; 11 ± 4 vs. 14 ± 4 mm, p = 0.23, length of P3; 8 ± 3 vs. 10 ± 3 mm, p = 0.13). Conclusions. Patients with remodeling of the lateral portion of PML tended to have recurrent MR after MAP. This factor could indicate progressive remodeling, and MAP alone may not be a sufficient intervention for these patients.