Three-Dimensional Mitral Valve Morphology in Children and Young Adults With Marfan Syndrome

Abstract

Mitral valve (MV) prolapse is common in children with Marfan syndrome (MFS) and is associated with varying degrees of mitral regurgitation (MR). However, the three-dimensional (3D) morphology of the MV in children with MFS and its relation to the degree of MR are not known. The goals of this study were to describe the 3D morphology of the MV in children with MFS and to compare it to that in normal children. Three-dimensional transthoracic echocardiography was performed in 27 patients (3-21years of age) meeting the revised Ghent criteria for MFS and 27 normal children matched by age (±1year). The 3D geometry of the MV apparatus in midsystole was measured, and its association with clinical and two-dimensional echocardiographic parameters was examined. Compared with age-matched control subjects, children with MFS had larger 3D annular areas (P<.02), smaller annular height/commissural width ratios (P<.001), greater billow volumes (P<.001), and smaller tenting heights, areas, and volumes (P<.001 for all). In multivariate modeling, larger leaflet billow volume in MFS was strongly associated with moderate or greater MR (P<.01). Intra- and interuser variability of 3D metrics was acceptable. Children with MFS have flatter and more dilated MV annuli, greater billow volumes, and smaller tenting heights compared with normal control subjects. Larger billow volume is associated with MR. Three-dimensional MV quantification may contribute to the identification of patients with MFS and other connective tissue disorders. Further study of 3D MV geometry and its relation to the clinical progression of MV disease is warranted in this vulnerable population.