An investigation into the frequency of mitral valve prolapse in von Willebrand disease.

The reported extremely high incidence of mitral valve prolapse in von Willebrand patients (60%) in combination with multiple signs of mesenchymal dysplasia points to a hitherto unknown pleiotropic effect of the von Willebrand gene and needs further confirmation. Therefore, we looked for the presence of mitral valve prolapse in 19 patients with classical von Willebrand disease. While 58% of these patients had one or more physical findings which could be interpreted as symptoms of mesenchymal dysplasia, we found only one patient with a mitral valve prolapse (5.3%), comparable to the 6% incidence in the normal population. Therefore, we must conclude that there is no association between mitral valve prolapse and von Willebrand disease.