Interrupted aortic arch variants

Interrupted aortic arch is classified according to location of the interruption. In type A, the interruption occurs distal to the left subclavian arterial origin. In type B, interruption occurs between the origins of the left common carotid and left subclavian arteries. In type C, interruption occurs proximal to the origin of the left common carotid artery. Blood flowing in the arteries proximal to the interruption is fully oxygenated, while blood flowing distal to the interruption is cyanotic. Type B is the most common form (>50%), followed by type A (approximately 40%). Type C is rare (<5%).