Congenital uni-leaflet mitral valve with severe stenosis: A case report with literature review.

Numerical abnormalities of mitral leaflets is a special entity in congenital mitral malformations. Previously reported cases of uni-leaflet mitral valve were primarily related to absence or dysplasia of certain leaflets. We present a case here with mitral leaflets that were not divided into anterior and posterior as usual, but developed as an integral structure instead, which is different from previously documented cases of uni-leaflet mitral valves. Real time three-dimensional echocardiography (RT3DE) provides a visual presentation of the abnormal mitral structure which was confirmed by surgical operation. To the best of our knowledge, this unusual form of uni-leaflet mitral valve has not been reported yet.