ABSTRACT
Developmental aspects and normal body configuration In contrast to other embryological organs, the thoracic and abdominal structures develop asymmetrically. There are well-defined right-sided and left-sided organs and structures. After completion of lateralization, the “normal” and most common condition found is then called situs solitus for the visceral arrangement, and levocardia (heart on the left side) for the thoracic arrangement (Figure 18.1). In Chapter 10, on fetal cardiac anatomy, the focus was on the segmental analysis of the upper abdomen and the heart, showing that under normal conditions, in situs solitus the stomach and descending aorta are on the left and the liver and the inferior vena cava on the right. The umbilical vein bends to the right, continuing with the portal sinus. In levocardia the heart apex points to the left anterior thoracic cavity with normal atrial and ventricular arrangement (Figure 18.1) and, under normal
conditions, the inferior vena cava is connected to the right atrium and the pulmonary veins to the left atrium.
