Mitral valve dimensions and motion in Marfan patients with and without mitral valve prolapse: Comparison to primary mitral valve prolapse and normal subjects

Abstract

To determine mitral valve and extravalvular findings associated with mitral valve prolapse (MVP) in patients with the Marfan syndrome, we compared mitral leaflet and anular dimensions and motion by computerized two-dimensional echocardiography in 53 Marfan patients (28 with M-mode echocardiographic MVP) to those in 48 adults with primary MVP and in 35 normal subjects. Mitral leaflet billowing occurred in 28 of 28 Marfan patients with M-mode MVP versus 24 of 48 with primary MVP (p < 0.00005), 0 of 25 Marfan patients without M-mode MVP, and 0 of 35 normal subjects (both, p < 0.00001). Billowing occurred on the first systolic frame in 8 of 28 Marfan-MVP patients, in whom posterior leaflet chordae arose abnormally from the posterior ventricular wall, and in no other subjects. These patients had large mitral valves and normal anular dynamics, whereas the remaining 20 Marfan-MVP patients had increased systolic anular expansion. Marfan-MVP patients were younger than those without MVP (29 ± 12 vs 38 ± 15 years, p < 0.02) and had lower body mass index (19.8 ± 2.7 vs 23.9 ± 2.9 kg/m2, p < 0.00005) and systolic blood pressure (120 ± 20 vs 133 ± 20 mm Hg, p < 0.05), similar to differences between primary MVP and normal subjects in body mass index (21.5 ± 3.0 vs 23.9 ± 4.8 kg/m2, p < 0.01) and systolic pressure (118 ± 14 vs 125 ± 18 mm Hg, p < 0.05). Marfan patients with and without MVP had similar arm span, arm span to height ratio, upper to lower segment ratio, and prevalence of ectopia lentis and thoracic bony abnormalities, but arachnodactyly was more frequent in those with MVP (82% and 48%, respectively; p < 0.02). We conclude that 1) leaflet billowing occurs more uniformly in Marfan patients with MVP than in primary MVP, 2) MVP in Marfan patients may be due to either valve enlargement with distinctively abnormal chordal architecture or abnormal mitral anular distensibility, 3) Marfan patients with MVP have low body weight and systolic blood pressure, similar to primary MVP, and 4) Marfan patients with MVP more commonly have arachnodactyly but otherwise have similar skeletal and anthropometric characteristics to other Marfan patients.