Fetal heart echocardiography at 20 weeks

One method I use for fetal echocardiography using color Doppler ultrasound:

• Zoom the fetal heart maximum, without losing the resolution of the image 
• Fetal heart color Doppler: Increase the PRF of the Doppler ultrasound maximum possible until color Doppler flow is just right and filling out the cardiac ventricles and aorta. 

In the image below, color gain is too high or PRF is too low to get a good flow study of fetal heart:

Now, I've increased the PRF, see below:

Flow signals are optimal: 4 chamber view, fetal heart:

Always see the 3 major vessels:

SVC, aorta,  pulmonary artery SAP in short. 

Finally have a look at the trachea and it's bifurcation: