Atrioventricular septal defects

Abstract

Atrioventricular septal defects (AVSDs) represent a wide spectrum of defects. Abnormal development of the endocardial cushions can lead to a spectrum of defects that are collectively referred to as AVSD. The presence and size of the ostium primum atrial septal defect (ASD) and inlet ventricular septal defect (VSD) varies and are considered when classifying the AVSD into its four subtypes. One consistent feature among all subtypes is the presence of a common AVV that is always at the same anatomic level within the ventricular mass. The valve may have a single orifice or be divided into two separate orifices by a bridging tongue of tissue. Although the nomenclature varies widely, the underlying anatomy and definitive surgical management of the four basic subtypes of AVSD will be addressed in this chapter.