Treatment for hypoplastic left heart syndrome requires open-heart surgery, either in the form of a transplant or a three-step series of operations called staged palliation. Transplant currently results in a lifetime of dependency on antirejection medications as well as a weakened immune system. Suitable donor hearts for babies also are always in short supply.
Staged palliation is considered one of the major achievements of congenital heart surgery in recent years. The survival rate for children at age 5 is about 70 percent and most of these children have normal growth and development. They will require life-long follow-up cardiac care as well as medication. They also will be more prone to heart valve infections, called endocarditis, and require antibiotics before surgery or dental treatment.
The procedures are timed to coincide with the development of the lungs. At the end of the procedures, the lungs allow deoxygenated blood to flow directly to the lungs and back into the heart without having to be pumped. The single ventricle created during the first procedure pumps oxygenated blood from the heart to the body.
- Norwood Procedure -- This procedure is performed shortly after birth. It converts the right ventricle into the main ventricle pumping blood to both the lungs and the body. The main pulmonary artery and the aorta are connected and the main pulmonary artery is cut off from the two branching pulmonary arteries that direct blood to each side of the lungs. Instead, a connection called a shunt is placed between the pulmonary arteries and the aorta to supply blood to the lungs.
- Bi-directional Glenn Operation -- This operation usually is performed about six months after the Norwood to divert half of the blood to the lungs when circulation through the lungs no longer needs as much pressure from the ventricle. The shunt to the pulmonary arteries is disconnected and the right pulmonary artery is connected directly to the superior vena cava, the vein that brings deoxygenated blood from the upper part of the body to the heart. This sends half of the deoxygenated blood directly to the lungs without going through the ventricle.
- Fontan Operation -- This is the third stage, usually performed about 18-36 months after the Glenn. It connects the inferior vena cava, the blood vessel that drains deoxygenated blood from the lower part of the body into the heart, to the pulmonary artery by creating a channel through or just outside the heart to direct blood to the pulmonary artery. At this stage, all deoxygenated blood flows passively through the lungs.