Genu VarumIsomerismHeterotaxy SyndromeHeart Defects, CongenitalHeart AtriaHeart Septal DefectsSitus InversusAbnormalities, MultipleVenae CavaeDextrocardiaLevocardiaHeart Bypass, RightPulmonary VeinsErythrocruorinsPulmonary Veno-Occlusive DiseaseGrowth Differentiation Factor 1Fetal HeartCyanosisAbortion, EugenicNodal ProteinAtrioventricular NodeFetal DiseasesVena Cava, InferiorFontan ProcedureAzygos VeinSinoatrial NodeTachycardia, Supraventricular