Atrioventricular septal defect (AVSD) – complete

In this condition, there is a defect in the lower part of the atrial septum and the inlet part of the ventricular septum with a common atrioventricular junction. The common atrioventricular valve bridges the defect. The defect is commonly associated with Down syndrome or atrial isomerism, although it can occur with normal situs in patients with normal chromosomes. The patient usually presents early in life with signs of congestive cardiac failure or failure to thrive. Corrective surgery is usually satisfactory although mitral valve incompetence can be a complication. Surgical repair to the valve is usually performed at the initial surgery but if severe incompetence persists valve replacement may be necessary. This is always problematic in children as long term anticoagulation therapy is required as well as subsequent valve replacement with growth of the child. The longest results available for the repair of an atrioventricular septal defect are for 20-30 years and are satisfactory. This condition may have a higher rate of recurrence in offspring than other forms of heart disease.