Class I recommendations of both American (2014) and European (2017) societies for severe primary mitral valve regurgitation are as follows: Mitral valve surgery is indicated in symptomatic patients with LVEF greater than 30% and in asymptomatic patients with LVEF of 60% or less McElhinney DB, Sherwood MC, Keane JF, et al Current management of severe congenital mitral stenosis: outcomes of transcatheter and surgical therapy in 108 infants and children Circulation 2005;112(5):707–714 Transcatheter dilation of mitral stenosis is effective, but postdilation regurgitation was shown to be associated with worst outcomes Surgery is preferred in cases with a supramitral ring Carpentier A Cardiac valve surgery—the “French correction.” J Thorac Cardiovasc Surg 1983;86(3):323–337 The reference article for the description of the functional classification and the techniques of mitral valve repair Many techniques applied in congenital mitral valve surgery derive from these original descriptions Abdullah I, Ramirez FB, McElhinney DB, et al Modification of a stented bovine jugular vein conduit (melody valve) for surgical mitral valve replacement Ann Thorac Surg 2012;94(4):e97– e98 The initial experience of the Boston Children's Hospital in mitral valve replacement with a stented bioprosthesis that can be further dilated This procedure has also been applied in aortic, pulmonary, and tricuspid positions References De Lange FJ, Moorman AFM, Anderson RH, et al Lineage and morphogenetic analysis of the cardiac valves Circ Res 2004;95(6):645–654 Angelini A, Ho SY, Anderson RH, Davies MJ, Becker AE A histological study of the atrioventricular junction in hearts with normal and prolapsed leaflets of the mitral valve Br Heart J 1988;59(6):712–716 Sun F, Chen Y, Ren W, et al Four-tiered echocardiographic analysis approach for congenital mitral valve malformations: four years of experience Int J Cardiol 2017;227:602–610 Silverman NH Echocardiography of congenital mitral valve disorders: echocardiographicmorphological comparisons Cardiol Young 2014;24(6):1030–1048 Layman TE, Edwards JE Anomalous mitral arcade A type of congenital mitral insufficiency Circulation 1967;35(2):389–395 Carpentier A, Branchini B, Cour JC, et al Congenital malformations of the mitral valve in children Pathology and surgical treatment J Thorac Cardiovasc Surg 1976;72(6):854–866