Hager, A; (Editorial)

 JACC; Volume 81, Issue 16, 25 April 2023, Pages 1601-1604

Infants with univentricular heart have only a single ventricle and initially a parallel circulation. The mixed blood of the single ventricle serves both the pulmonary circulation and the systemic circulation. Most patients nowadays get a palliation into a serial circulation according to the Fontan principle: the central venous blood bypasses the right ventricle into the pulmonary arteries. The staged Fontan palliation is performed, with a first stage within the first weeks of age stabilizing the parallel circulation, a second-stage in infancy with a superior cavopulmonary anastomosis and a third stage in early childhood with the completion by an inferior cavopulmonary anastomosis. Up to the third stage, there is still a substantial mortality depending on the details of the primary heart defect. At and after the third stage, there is only a minimal mortality throughout childhood, and most of these patients reach adulthood……etc.