Ventricular dysfunction is a common problem in many adults with congenital heart disease and is particularly common in those born with transposition of the great arteries. Simple transposition (d-transposition) is the most common cyanotic abnormality in newborns, in which the right atrium is connected to the RV (atrioventricular [AV] concordance) which, in turn, gives rise to the aorta (ventriculo-arterial discordance). The left atrium enters the LV, which gives rise to the pulmonary artery. Since the 1980s, this defect has usually been repaired in infancy with an arterial switch procedure so that the LV is restored to function as the systemic ventricle. In the 1960s, however, the only reparative procedures were the Mustard or Senning operations that redirect the blood flow via an atrial baffle so that venous blood is directed into the LV and then to the pulmonary artery, and pulmonary venous blood is directed to the RV and thence to the aorta. These operations resulted in a dramatic improvement in the lives of cyanotic infants, who were rendered pink and healthy, most of whom continue to do well three decades later. Long-term problems are inevitable, however, particularly as the morphologic RV continues to function as the systemic ventricle This may function well for decades (43), but function deteriorates eventually, often with concomitant tricuspid regurgitation (44- 45). Pulmonary artery banding to “retrain” the LV followed by an arterial switch operation has provided improvement in systemic ventricular function in some young patients and adolescents, but results of LV “conditioning” have been less consistent in adults (46). As a result, this approach has been largely abandoned in adults in favor of cardiac transplantation.