Normal fetal echo quiz

Name the structures marked by the numbers 1,2 and 3 in this fetal echo of a 28 week fetus:
Still image is shown below:

The ultrasound video of this same case is shown below:

Hint: see: http://www.ultrasound-images.com/normal-anatomy.htm#Normal_3_vessel_view_in_a_28_week_fetus

The ductus and 3 vessel view in 30 week fetus

Just some stunning ultrasound and color Doppler images and a video of the 3 vessel view during fetal echo in a 30 week fetus. In the color Doppler image below, the right pulmonary artery is seen crossing behind the ascending aorta (left half of image). The ductus arteriosus (red) is seen merging with the aortic arch (blue) to the left of the spine (right half of image).

Image below shows details of the 3 vessel view.

The video below shows the 3 vessel view again in this 30 week fetus. The visualization of the ductus may vary depending on imaging conditions.