Transverse sweep starting from the abdomen and moving towards the upper mediastinum.  This clip will be ‘broken down’ into different levels of scanning planes - further explained in the following images.

Transverse view of the fetal abdomen at the level of the stomach.

By knowing fetal lie and the position of the spine, it is possible to determine right and left sides of the fetus. In this example, the fetus was in cephalic position (or head down in relation to the scanning plane). With the spine being posterior, the left side corresponds to where the stomach is.

Four-chamber view. This clip shows a heart of normal size (≈ 1/3 of the area of the chest) which is left-sided with apex pointing to the left. The cardiac axis is normal (≈ 45º). There is symmetry between right and left-sided cardiac structures. The 2 valves (tricuspid and mitral valves) show normal offsetting (tricuspid displaced more apically), open freely and close appropriately. The moderator band is seen within the right ventricle (right-sided). The foramen ovale is patent with its flap valve in the left atrium. The interventricuar septum is intact. Cardiac contractility is normal. Cardiac rhythm is regular and heart rate appears to be within normal range.

Left ventricular outflow tract. This view shows a vessel arising entirely from the left ventricle. It appears to be the aorta as it runs towards the right shoulder. There is normal continuity between the interventricular septum and the anterior wall of the aorta. The aortic valve opens and closes normally.

This clip starts at the level of the left ventricular outflow tract with aorta arising from this ventricle and continues to show the vessel arising from the right ventricle (pulmonary artery). Note the ‘cross-over’ of the two vessels at their origin when moving the clip between aorta and pulmonary artery.
This clip also shows the normal alignment of the 3 vessels (superior vena cava, aorta and pulmonary artery – from right to left) which corresponds to the 3-vessel view (3VV).  Further cephalad from this, the transverse aortic arch is also shown. At this level, the trachea is also imaged. The aortic arch is seen to be to the left of the trachea . This corresponds to the 3-vessel and trachea view (3VTV).
The use of colour flow mapping facilitates recognition of various structures and adds information regarding flow velocities (scale not shown).