Double mitral valve. Report of a case and review of the literature.

A case of double mitral valve orifice associated with atrioventricular canal was found at operation. These two anomalies are frequently associated. Double mitral valve is usually subclinical and does not necessarily need to be corrected, depending on the associated anomalies, the extent of the defect, and the personal experience of the surgeon. The embryology of double mitral valve is complicated and still needs to be clarified.