Surgical treatment of floppy mitral valve syndrome in children.

Five children whose ages ranged from 9 to 14 years underwent operation for floppy mitral valve syndrome. The clinical course of this syndrome in young patients was characterized by exceptionally rapid deterioration in congestive heart failure after the onset of symptoms. The children responded poorly to medical treatment. Early surgical treatment should be recommended soon after the onset of congestive heart failure. Three out of 5 patients required an associated tricuspid valve replacement for a floppy tricuspid valve, whose structure showed marked myxomatous transformation. Because of the high incidence of myxomatous transformation of the tricuspid valve in children, significant tricuspid insufficiency in this syndrome should be managed by valve replacement.