The subcostal view is an excellent view to profile the outflow tracts and confirm the diagnosis of transposition of the great arteries. The pulmonary artery can be seen arising more posteriorly from the left ventricle and bifurcating and the aorta can be seen arising more anteriorly from the right ventricle. VSDs can also be demonstrated and profiled from this view. Patients with transposition can often have large VSDs with posterior malalignment of the ventricular septum causing varying degrees of subpulmonary/pulmonary stenosis (left sided ouflow tract).
Transducer on abdomen just below xyphoid process
Notch at 3 o'clock
Transducer tilted slightly anteriorly (tail down)
Full sweeps from anterior to posterior to define outflow tract origin and position