There have been many improvements in the care of children with hypoplastic left heart syndrome (HLHS). This has helped these children survive longer. Because these children now live longer, researchers are recognizing developmental disabilities (the children are behind in their thinking or physical activity) in children with hypoplastic left heart syndrome. The purpose of this research study is to help the investigators learn more about developmental disabilities in children with hypoplastic left heart syndrome.

During the time of your child's first surgery for hypoplastic left heart syndrome, a monitor was placed on your child's forehead to measure the oxygen levels in the brain. This monitor is called Near Infrared Spectrometry (NIRS). The researchers involved in this study want to know if oxygen levels in the blood vessels of the brain have any effect on developmental disabilities later in life in children with hypoplastic left heart syndrome. The researchers plan to enroll 60 research subjects.

Our study is a cross-sectional, descriptive study to evaluate the developmental outcome for school-age children with HLHS. The general approach of the proposed research is confirmatory study/hypothesis testing. The hypothesis (neurodevelopmental outcome of children with HLHS is inversely correlated with cerebral oximetry values as measured by NIRS in the 48 hours following the Norwood operation) was formulated based on a meticulous review of the literature, which clearly demonstrates a substantial prevalence of neurodevelopmental deficits in children with HLHS who have undergone surgical palliation. The methodologies for measuring developmental outcome are highly reproducible and have been validated in this population.

Inclusion Criteria:

1. Hypoplastic left heart syndrome is defined as normal segmental anatomy with mitral and/or aortic atresia or stenosis and a left ventricle too small to sustain the systemic circulation
2. Ages 2.5 to 6 years old
3. Surgical palliation with the Norwood procedure (Stage I palliation) at Children's Healthcare of Atlanta after January 1, 2001

Exclusion Criteria:

1. Primary language in the home is not English
2. Named genetic syndrome associated with profound developmental delay, such as DiGeorge Syndrome

Children ages 2.5 to 6 years old who have hypoplastic left heart syndrome with surgical palliation and near infrared spectrometry monitoring during the Stage I Norwood procedure.