부산대학교 도서관

Background: We previously reported that atrial functional mitral regurgitation (A-FMR) occurs with morphological changes of the mitral valve and can be improved by catheter ablation (CA) of atrial fibrillation (AF). However, it is unclear whether the unique morphological changes in the time-course of AF persistence are reversible with sinus rhythm restoration with CA.Aims: The aims of this study were 1) to compare morphological differences among paroxysmal AF (PAF) w/o MR, non-paroxysmal AF (NPAF) w/o MR, and A-FMR, and 2) to examine changes in degree of MR and morphology of the mitral valve after CA in patients with A-FMR.Methods: This is a multicenter (4 hospitals in Fukuoka) retrospective observational study. Protocol 1: Eighty-four patients undergoing initial CA for AF (from 2010.January to 2021.May) were selected and divided into 3 groups after matching on age (68±8 y.o), sex (19 males), and body surface area (1.7±0,2 m); PAF w/o MR, NPAF w/o MR, and A-FMR (n=28 in each group). A-FMR was defined as at least mild MR accompanying with NPAF, preserved LVEF (≧ 50%), and no evidence of valve degeneration and other structurally heart diseases. Protocol 2: Fifty-five patients with A-FMR (19 males, 71±9 y.o.) undergoing initial CA were enrolled. Clinical variables and echocardiographic parameters were analyzed.Results: In protocol 1, tethering angles of anterior and posterior mitral leaflet (AML and PML) were smaller in patients with A-FMR compared with PAF w/o MR (Table1). PML length was shorter in A-FMR than other groups (Table1). In protocol 2, the degree of MR was significantly reduced (Figure, p=0.0013) associated with reduction in MR vena contracta width and MR area (p<0.001) at 11±7 months after CA. Tethering angles of AML and PML were increased after CA (Table2).Conclusion: A-FMR occurs via unique morphological changes of the mitral apparatus along with AF persistence and can be improved by CA of AF with significant reversals of the morphological changes.