In hypoplastic left heart syndrome, the left side of the heart — including the aorta, aortic valve, left ventricle and mitral valve — is underdeveloped. Blood returning from the lungs must flow through an opening in the wall between the atria, called an atrial septal defect (ASD) or patent foramen ovale (PFO). The right ventricle pumps the blood into the pulmonary artery, and blood reaches the aorta through a patent ductus arteriosus (PDA). The baby often seems normal at birth but will need medical attention within a few days as the ductus closes.
This heart defect is usually fatal within the first days or months of life without treatment. It isn't correctable, but some babies can be treated with a series of operations or with a heart transplant.
Heart with Hypoplastic Left Heart Syndrome
Early and prompt treatment is critical for the best outcome after birth because it is normal for a section of the heart called the patent ductus arteriosus (PDA) to begin to close and look quite ill. The PDA can be seen in the illustration above.
A medicine called prostaglandin will be given to your child until the first stage operation is performed. This medicine helps keep the heart structures open. A heart transplant is an option, but donor organs for infants are rare. Therefore, the most patients undergo three stages of surgical procedures, which are described below.
After your baby is born, intravenous prostaglandin will be used to help provide a stable blood flow using your child’s patent ductus arteriosus for perfusion to the body and lungs. This medicine allows time for your team to take the images needed to help provide the best care for your child.
The first surgical procedure is done to help the right ventricle to pump blood to the body. There are three approaches (Hybrid, Norwood with a BT shunt, or Sano with RV to PA conduit) based on your child’s anatomy, size and other circumstances. Your care team will discuss these options with you.
If your baby does not already have an existing hole between the upper chambers of the heart, called an atrial septal defect or ASD, an additional procedure is required to open the flow between the upper chambers.
The first stage of surgery often leads to the longest hospitalization of all three surgeries. It also requires the most intensive management after discharge. Instructions will be provided by your health care team in the Regenstein Cardiac Care Unit (CCU). The HeArT Clinic will help prepare you for this journey and make sure you have all the tools and resources during the interstage period and beyond.
The second stage is called a bi-directional Glenn, or hemi-Fontan operation, and consists of disconnecting the shunt to the pulmonary arteries and connecting the superior vena cava directly to the right pulmonary artery. With this, the heart volume is unloaded by directing blood flow from the upper body directly to the pulmonary artery. Your child is more stable in this state. Your child's care, including the home surveillance monitoring program (scroll down for more information), is less intense in this stage. It is very common for infants to have similar oxygen saturations after the second-stage palliation as the first-stage palliation.