Only the left atrium is connected to a ventricle (univentricular atrioventricular connection).
An imperforate valve can be found in the setting of double inlet ventricle, or with any of the possible biventricular atrioventricular connections.
These panels show (upper) absence of the right atrioventricular connection, but with the left atrium connected to a dominant right ventricle.
Perimembranous defects are found only when there are biventricular atrioventricular connections, or else when the right ventricle is dominant.
The echocardiographic diagnosis was presence of a solitary ventricle with a single atrioventricular valve and an atrial septal defect.
These septal areas can be absent entirely or in part in lesions such as double inlet ventricle or absence of one atrioventricular connection.
The category of univentricular connections includes double inlet ventricles, along with absence of one atrioventricular connection.
We recently encountered two such cases, both with the segmental combination of mirror-imaged atrial arrangement, discordant atrioventricular connections, and double outlet right ventricle.
