Comparison of cardiovascular and skeletal features of primary mitral valve prolapse and Marfan syndrome.

The association of primary mitral valve prolapse (MVP) with thoracic bony abnormalities has led to the suggestion that MVP may be a forme fruste of the Marfan syndrome. Echocardiographic, skeletal and anthropometric findings in 59 subjects with primary MVP and 59 age- and sex-matched patients with Marfan syndrome were compared with those in 59 control subjects. Subjects with mitral prolapse were similar to control subjects and differed (p less than 0.025 to p less than 0.001) from the patients with Marfan syndrome in aortic root dimensions, height, arm span, upper/lower segment ratio and prevalences of arachnodactyly, scoliosis and pectus carinatum. Subjects with mitral prolapse and patients with Marfan syndrome had similar body mass indexes and prevalences of pectus excavatum and straight back. All 3 groups were similar in arm span/height ratio. The 5 subjects with MVP and arachnodactyly had lower weights, smaller body surface areas and smaller aortic root dimensions, and were more likely to have scoliosis than subjects with MVP without arachnodactyly. Thus, primary MVP differs from the Marfan syndrome in all major skeletal and cardiovascular features.