Abstract 16986: Mechanism of Atrial Mitral Regurgitation -An Echocardiographic Study-

Introduction: The purpose of this study was to investigate potential causes of mitral regurgitation (MR) in chronic atrial fibrillation using real-time three-dimensional transesophageal echocardiography (3D TEE). Methods: Patients undergoing MitraClip at our institution from 2007 to 2016 were reviewed (n=309). There were 45 chronic atrial fibrillation (AF) patients with normal leaflet motion who had at least moderate MR. Patients were classified into two groups: one, those without left ventricular dilatation (atrial MR (figure 1-A), n=19), the other, with left ventricular dilatation (functional MR (figure 1-B), n=26). Left ventricular ejection fraction, left atrial (LA) volume, peak pulmonary artery pressure (PAP), e’ (lateral), 3D mitral valve annular area (MAA), tenting height, tenting volume were compared between two groups. Changes in MR severity, LA volume and PAP after the clip procedure were also compared between the 2 groups. MR severity was graded as follows; trivial-mild=1, moderate=2, moderate-...