The right ventricle performs the traditional job of the left, supplying the body with oxygenated blood, while the passive systemic venous pressure performs the traditional job of the right, passing deoxygenated blood to the lungs. Fetal surgery
Interventions performed during fetal development are under investigation. In fetuses with hypoplastic left ventricles and an intact interatrial septum, percutaneous atrial septostomy has been attempted. Prognosis
95% of untreated infants with HLHS die in the first weeks of life.Early survival has improved since the introduction of the Norwood procedure. Since there are no long-term studies of HLHS adults, statistics are usually derived from post-Fontan patients; it is estimated that 70% of HLHS patients may reach adulthood.Prognosis is dependent upon the health of the child, as there is an increased demand on respiratory and heart rate in infants during common childhood illnesses. This fragile population has little cardiac reserve to accommodate these demands and provide hemodynamic stability during illnesses.Children with HLHS and other comparable single-ventricle conditions, as a group, have poorer neurodevelopmental outcomes than their healthy peers. Deficits in language, executive functioning, and higher rates of anxiety and depression disorders have been demonstrated. Some of these outcomes may be a consequence of genetic factors associated with HLHS, and others may be modifiable through changes to procedures and to the healthcare environment. There is an emerging clinical consensus around the importance of continuous neurodevelopmental surveillance from the earliest years into adulthood.
8p23.1 duplication syndrome is a rare genetic disorder caused by a duplication of a region from human chromosome 8. This duplication syndrome has an estimated prevalence of 1 in 64,000 births  and is the reciprocal of the 8p23.1 deletion syndrome. The 8p23.1 duplication is associated with a variable phenotype including one or more of speech delay, developmental delay, mild dysmorphism, with prominent forehead and arched eyebrows, and congenital heart disease (CHD). Presentation
The phenotypic data on 11 patients indicated that cases are not always ascertained for CHD but that CHD was the most common single feature found in 6 out of 11 individuals. Developmental delay and/or learning difficulties were found in 5 out of 11 cases, but one prenatal case was developing normally at 15 months of age (Case 1,). Three other prenatal cases could not yet be reliably assessed. A variable degree of facial dysmorphism was present in 5 out of 11 individuals. Partial toe syndactyly has been found in one mother and son diad and adrenal anomalies in two probands but not in the duplicated mother of one of them. The phenotype is compatible with independent adult life with varying degrees of support. Duplication of the GATA4 transcription factor (OMIM: 600576) is believed to underlie the congenital heart disease and other genes, common to the duplication and deletion syndromes, can be regarded as candidates for the 8p23.1 duplication syndrome. These include the SOX7 transcription factor (OMIM: 612202) for both CHD and developmental delay  and the TNKS gene (OMIM: 603303) for behavioural difficulties.