Conceptual relationships between IS and VIF in abnormal ventriculo-arterial connections in situs solitus and atrio-ventricular concordance. 1A Normal relationships. 1B TF. Anterior deviation/displacement of the IS (compare to Figure 4). 1C DORV with sub-aortic VSD. The AL blends or is committed to the counter-clockwise twisted IS. The PL blends or is committed to the VIF (compare to Figure 5). 1D Taussig-Bing (DORV with sub-pulmonary VSD). The PL blends or is committed to a more counter-clockwise twisted IS (compare to Figure 8). 1E TGA. The IS inserts abnormally to the TSM forming a totally displaced infundibulum (compare to Figure 9). 1F and 1G Absent IS in truncus arteriosus and doubly committed juxta-arterial VSD. The PL still blends or is committed to the VIF of the single outlet or of the aorta (compare to Figure 7 and 6).