Few congenital heart malformations have raised as many surgical, ethical, social and economic issues as the therapy for infants born with hypoplastic left heart syndrome (HLHS). HLHS was first described by Lev in 1952 and named in 1958 by Noonan and Nadas. It has been reported to occur in approximately 0.016% to 0.036% of live births in Canada and the United States. Thus, each year approximately 56 to 126 infants in Canada and 640 to 1440 infants in the United States are born with HLHS. HLHS represents 2% to 9% of congenital heart disease cases and accounts for 23% of neonatal deaths from congenital heart malformations.