Absent inferior vena cava, symmetrical liver, splenic agenesis, and situs inversus, and their embryology.

Several cardiac malformations are known to be associated with situs inversus In addition, there are often some venous and visceral malforma- tions, e.g. bilateral superior venm cavae (SVC), absence of a segment of the inferior vena cava (IVC), agenesis of the spleen, and symmetry of the liver. We shall discuss these five malformations, particularly the correlations between them, and whether their embryological development provides any ex- planation for the correlations.