Seraph was born with an unbalanced Atrioventricular Septal Defect (AVSD)(aka CAVC - complete atrioventricular canal defect) with hypoplasia of the right ventricle. Also, her heart is mirrored - so she has a left-sided right atrium and a right-sided left atrium, etc..
Stay with me - it's not as hard as it sounds.
"Atrio" - from atria which are the upper chambers of the heart
"ventricular" - from ventricles which are the lower chambers of the heart
"Septal" - from septum which are the dividing walls or the heart
"hypoplasia of the right ventricle" - meaning her right ventricle is unusually small compared to the rest of her heart.
Here's a normal heart:
The blue blood goes out (thru the pulmonary artery) to the lungs where it picks up oxygen.
Here's a heart with AVSD (Atrioventricular Septal Devect) aka CAVC (complete atrioventricular canal defect):
Remember: Seraph's heart is flipped. So her heart is a mirror image of these pictures. Also, her right ventricle is too small compared to the rest of her heart.
Seraph's first surgery - the Norwood Procedure (11 days old) (not shown in picture - hole between the two ventricles)
a--improve the flow of red blood (oxygenated blood) around the body by attaching the base (Trunk) of the lung artery (Pulmonary Artery) to the body artery (Aorta).
b--provide a blood flow to the lungs through a passage (Shunt), creating a link between the lung artery (Pulmonary Artery) and the body artery (Aorta). The passage is made out of soft plastic (Gore-Tex).
c--I don't think they had to enlarge the atrial septal defect, but I'm not positive.
Seraph's second surgery - Cavo Pulminary Connection (4-6 months old)(not shown in picture - hole between the two ventricles)
--redirect the flow of blue blood (deoxygenated blood) to the lungs by attaching the upper body vein (Superior Vena Cava) directly on to the lung artery (Pulmonary Artery).
The Gore-Tex shunt that was inserted at the last operation will be taken away.
Seraph's third surgery - Fontan Procedure (2-5 years old)(not shown in picture - hole between the two ventricles)
--aims to separate the blue (deoxygenated) blood supply and the red (oxygenated) blood supply
--create a wall (baffle) in the right collecting chamber (Right Atrium) and then attach the chamber to the base of the lung artery (Pulmonary Artery)
All the returning blue (deoxygenated) blood will now be flowing to the lungs, without a pump behind it. This causes an increase in pressure within the lung blood vessels, so, to aid circulation, a small hole (fenestration) may be created in the wall (baffle). This acts as a pressure release valve whilst the child’s body adjusts to their new circulation.
They monitor the oxygen levels in her blood--when it's too low they know it's time for the next surgery. She'll end up with just one ventricle pumping oxygen-rich blood to her body. Her deoxygenated blood will flow to her lungs without a pump.
She may need a heart transplant in her 20's.