Physiology The human circulatory system uses a low-resistance pulmonary circulation and high-resistance systemic circulation to pump blood. In a single-ventricle heart, the sole functioning ventricle must pump blood to both the lungs and the organ systems. As a result, this is an abnormal parallel circuit where the pulmonary and systemic blood mixes such that both oxygenated and deoxygenated blood are pumped to the organs. The aim of the<unk><unk>  shunt is to improve oxygenation and reduce the load on the single functioning ventricle while the patient is prepared for definitive surgical correction through separation of the pulmonary and systemic circuits. The<unk>  shunt is also called a "hemi-Fontan" procedure because it is the physiologic equivalent of half a functioning Fontan shunt. Univentricular congenital cardiac malformations The incidence of univentricular heart malformations is estimated at 0.1 to 0.4 per 1,000 live births. In the neonatal period, these patients depend on an aortopulmonary shunt that is maintained medically with prostaglandin and then surgically with an initial cardiac shunt procedure. As the patient will outgrow the shunt with time, they are evaluated for the<unk> <unk>  shunt when oxygen saturation begins to fall. The<unk>  procedure is typically performed at 4 to 6 months of age for infants born with congenital single ventricle defects. These patients typically require a Fontan procedure at 18 to 36 months of age following the<unk> <unk>  procedure. Examples of congenital cardiac malformations in which this procedure may be used include hypoplastic left heart syndrome, tricuspid atresia, double-inlet left ventricle and double-outlet right ventricle. The natural history of congenital univentricular cardiac malformations results in cyanotic heart failure at an early age. Staged palliation through the<unk>  shunt and Fontan procedure has allowed these patients to live into adulthood.
Bidirectional Glenn procedure
Distal splenorenal shunt procedure
Portacaval anastomosis
Hepatoportoenterostomy
Jejunoileal bypass
Peritoneovenous shunt
Transjugular intrahepatic portosystemic shunt
Portosystemic shunt