Coarctation of the aorta is often considered a critical congenital heart defect (critical CHD) because if the narrowing is severe enough and it is not diagnosed, the baby may have serious problems soon after birth. CCHDs also can be detected with newborn pulse oximetry screening.

On the left, it branches directly from the arch of aorta. The subclavian artery travels laterally towards the axilla. It can be divided into three parts based on its position relative to the anterior scalene muscle: First part – origin of the subclavian artery to the medial border of the anterior scalene.

The aortic arch has three main branches on its superior aspect. The first, and largest, branch of the arch of the aorta is the brachiocephalic trunk, which is to the right and slightly anterior to the other two branches and originates behind the manubrium of the sternum.