This page is a work in progress. I’ve noticed that some people are finding our blog by searching for heart defects similar to Matthew’s, and I wanted to provide some more detailed information.
Matthew’s heart defect was called a Complete Atrioventricular Canal. This is basically a gigantic hole in the center of the heart. In medical terms, the defect has several components:
- ASD or Atrial Septal defect. This is a hole between the top chambers of the heart
- VSD or Ventricular Septal defect. This is a hole between the bottom chambers of the heart
- Valvular defect. The two valves that normally separate the top and bottom chambers were fused into one common valve.
A Normal Heart:
Complete Atrioventricular Canal:
Valves with a Complete AV Canal:
The surgery to repair this defect involves patching the ASD and VSD, and separating the common valve into two separate, functional valves. This is a complicated surgery, but is done with a very high success rate.
Surgeons rebuild the walls of the heart with a patch, which is usually made out of a piece of tissue taken from the pericardium (sac around the outside of the heart). Then, the valves are reconstructed and attached to the patch. This is the tricky part of the surgery, as the one common valve can be complex to repair. The surgeon does his best to create valves that are tight enough not leak (medically, “regurgitation”), but loose enough to not become stiff and hard (“stenotic.”)
This surgery really does have a very high success rate – “success” meaning the heart is effectively repaired and the child survives the surgery and goes on to have many years of a good quality of life. However, as with any surgery, there are risks involved.
- The main risk is that years after the surgery, one of the repaired valves may become too stiff or too leaky to be effective, and may need to be replaced.
- When the patch is placed in the ventricular septum, there is a 5-20% chance that the electrical conduction system of the heart will be damaged. This can lead to “heart block” and the possibility of the need for a permanent pacemaker. This is why we were so relieved that the VSD portion of Matthew’s heart defect healed spontaneously!
- Children with Down Syndrome are at increased risk of post operative complications such as infections and lung problems – specifically pulmonary hypertension (increased blood pressures in the lungs, which can lead to fluid-overload in the lungs). In fact, pulmonary hypertension is more common in kids with Down Syndrome with or without the presence of other congenital heart defects.