[Echocardiographic diagnosis of accessory leaflet of mitral valve].

The accessory mitral valve leaflet is a rare cardiac congenital anomaly usually associated to complex cardiac congenital malformations. It also represents a rare cause of left ventricular outflow tract obstruction. Its diagnosis has often been ignored by conventional diagnostic methods. This fact may represent a cause for relative surgical failure, when operations for cardiac complex anomalies are performed. Echodopplercardiography is the choice and more accurate method for its diagnosis. In our case, parasternal and apical long axis planes, allowed an unmistakable visualization of a parachute shape fibrous structure, with its concave surface turned up towards the aortic valve. Chordae tendinae proper to the anomalous accessory mitral valve tissue were connected to chordae or to papillary muscles of the mitral valve. A careful echodopplercardiographic study will allow us, not only to diagnose this malformation, as well as to differentiate it from other conditions like tumors, vegetations or other types of subaortic obstruction.