Atrioventricular Septal Defects

Abstract

The atrioventricular septal defects (AVSDs), also referred to as atrioventricular canal defects or endocardial cushion defects, encompass a wide spectrum of anatomic findings. The pathognomonic feature of this group of hearts is a common atrioventricular junction . AVSD represents a spectrum of cardiac anomalies subdivided into partial, intermediate, and complete AVSDs. Patients with an AVSD initially have excessive pulmonary blood flow resulting from left-to-right shunting at the atrial and ventricular levels. If there is no interventricular communication, the hemodynamics are similar to those of a large atrial septal defect, with increased right ventricular stroke volume. In patients with a partial AVSD, surgical repair is usually performed electively between 1 and 2 years of age. Approximately 5% of patients with complete or partial AVSD will have a double-orifice left atrioventricular valve.