What are they?
Rare disorders affecting one lower chamber of the heart. The chamber may be smaller, underdeveloped, or missing a valve.
Hypoplastic Left Heart Syndrome (HLHS) - An underdeveloped left side of the heart. The aorta and left ventricle are too small and the holes in the artery and septum did not properly mature and close.
Pulmonary Atresia/Intact Ventricular Septum - The pulmonary valve does not exist, and the only blood receiving oxygen is the blood that is diverted to the lungs through openings that normally close during development.
Tricuspid Atresia - There is no tricuspid valve in the heart so blood cannot flow from the body into the heart in the normal way. The blood is not being properly refilled with oxygen so it does not complete the normal cycle of body -heart –lungs- heart - body.