4D velocity acquisition plane location for flow investigation. (A) Anterior view of the Fontan circuit and aortic arch with visualized pathlines within the IVC, LPA, RPA and SVC. (B) Posterior view of the Fontan circuit, aortic arch and pulmonary veins with visualized pathlines within the pulmonary veins. (C) Sagittal view of the aortic arch with visualized pathlines. AO, aorta; IVC, inferior vena cava; LLPV, left lower pulmonary veins; LPA, left pulmonary artery; LUPV, left upper pulmonary veins; RLPV, right lower pulmonary veins; RPA, right pulmonary artery; RUPV, right upper pulmonary veins.