Complete atrioventricular septal defect

This is a congenital heart defect caused by a hole in the wall separating the left and right chambers of the heart. This communication affects both the atria (the upper chambers) and the ventricles (lower chambers).

The cause of the defect is the formation of endocardial cushions, which are responsible for the creation and joining of the atrioventricular valves with the cardiac septum, the  wall that separates the two chambers.

This heart defect is also characterised by having just one atrioventricular valve  in place of two; the tricuspid and mitral valves.

Symptoms

Children with this heart defect show classic symptoms of heart insufficiency or failure. This includes frequent respiratory infections, difficulty feeding and gaining weight.

Who is affected by complete atrioventricular septal defect?

This makes up 4 % of all heart disease and around half of the heart defects that affect children with Down's syndrome.

Diagnosis

Diagnosis is via 2D echocardiogram.

Typical treatment

New-born babies tend to undergo surgery for this heart defect when they are six months old. The procedure consist of closing the interventricular or interatrial hole using a patch. The atrioventricular valve is also reconstructed to create a valve on the right side and another on the left.

In children under six months with severe symptoms, a prior palliative procedure called pulmonary cerclage is carried out. This procedure is carried out by narrowing the pulmonary artery using a band to decrease excessive pulmonary flow.