Q21.2: Atrioventricular septal defect

You have holes in your cardiac septum, the wall between the left and right sides of your heart. You have a hole in the septum between the two upper chambers (atria) and in the septum between the two lower chamber (ventricles). This condition is congenital, which means you were born with it.

The heart pumps blood through the body. Inside the heart are 4 chambers. There are 2 heart atria and 2 ventricles. Both heart atria and both ventricles are separated from each other by a partition.

A hole in the cardiac septum may develop during development in the womb before birth. The cardiac septum sometimes fails to close up as normal during development. A hole in the cardiac septum can result in blood flowing back and forth directly between the upper chambers (atria) or lower chambers (ventricles). This usually results in a change to normal blood flow. In some cases, this means that the heart and lungs are placed under greater strain. The blood supply to the body may also be impacted due to a hole in the cardiac septum.

You have a hole in the cardiac septum between your atria and between your ventricles. This may mean that all heart chambers are directly connected to one other, causing blood to flow back from the left side of the heart directly into the right side of the heart because the blood pressure in the left heart is normally higher than in the right heart. However, in your case, blood flows back through the lungs. The additional blood flow puts the heart and lungs under greater strain than normal. This can cause increased pressure in the pulmonary vessels, for example. If there is increased pressure in the pulmonary vessels, blood also flows directly from the right heart into the left heart. The holes in the cardiac septum mean that the heart can no longer pump blood adequately through the body,

usually causing severe symptoms in early childhood. This often causes rapid breathing and shortness of breath. The lungs may also become inflamed more often than normal. Often, a hole in the cardiac septum means the body finds it more difficult to grow. The liver is also greatly enlarged in many cases.

The bigger the hole in the cardiac septum between the atria and between the ventricles, the sooner symptoms will appear. Often, the symptoms are also more severe with a larger hole. Having only a small hole in the septum may mean that you don’t have any symptoms at all.