This complex defect is best described as a large hole in the middle of the heart. It results from a lack of separation of the atria and the ventricles into separate chambers, and a lack of separation of the mitral and tricuspid valves into two separate valves. This results in a large connection between the two atria, between the two ventricles, and a single atrioventricular (or AV) valve where there should be separate mitral and tricuspid valves. In the most complex form of this defect, not only are there holes between the atria, the ventricles, and the mitral/tricuspid valves, one of the ventricles may not be properly formed, the valves may be 'over-riding' or 'straddling', or there may be an obstruction to the aorta. Because of the large amount of extra blood going to the lungs (through the septal defects), high blood pressure may occur and over time this can damage the blood vessels. In addition, the valve between the upper (atrial) and lower (ventricular) chambers might not close properly. Blood then leaks backward from the ventricular chambers to the atrial chambers. This leak is referred to as regurgitation or insufficiency of the valve. When the valve leaks, the heart has to pump more blood. This can lead to enlargement of the heart.
This defect is usually corrected in infancy with open heart surgery to restore normal blood circulation through the heart. Surgical repair consists of separation of the common AV valve into two valves, along with closure of the VSD and ASD. Some children, however, may have too complex a defect to correct in infancy, and would initially require a pulmonary artery banding. This will decrease blood flow and reduce the high pressure in the lungs. When the child is older, the band will be removed and the defect corrected with open heart surgery.
Atrioventricular canal occurs in two out of every 10,000 live births, and equally in boys and girls
This defect is usually corrected in infancy with open heart surgery to restore normal blood circulation through the heart. Surgical repair consists of separation of the common AV valve into two valves, along with closure of the VSD and ASD. Some children, however, may have too complex a defect to correct in infancy, and would initially require a pulmonary artery banding. This will decrease blood flow and reduce the high pressure in the lungs. When the child is older, the band will be removed and the defect corrected with open heart surgery.
Atrioventricular canal occurs in two out of every 10,000 live births, and equally in boys and girls