Hemitruncus:
Clinical:
In hemitruncus the left pulmonary artery arises normally from the right
ventricle, while the right pulmonary artery arises from the ascending aorta.
Patients are not cyanotic and there is an associated PDA in about 80% of
cases.
X-ray:
CXR demonstrates asymmetric pulmonary blood flow- increased to the side
that the pulmonary artery arises from the aorta. Differential considerations
for this finding include: Tetrology of Falot- the right lung tends to demonstrate
more prominent flow; Truncus- with peripheral pulmonic stenosis; Pulmonic
stenosis- left lung typically has increased flow; and Post-op shunting.
