Endothelioma of the mitral valve.
D005260:Female; D006338:Heart Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D006390:Hemangioendothelioma / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008854:Microscopy, Electron; D008875:Middle Aged; D008943:Mitral Valve / Q000473:pathology