Abstract This chapter provides an overview of two aortic arch anomalies, the common coarctation of the aorta and the rare interrupted aortic arch These lesions are outlined, describing their morphology on a spectrum from discrete coarctation through tubular hypoplasia and finally progressing to interrupted aortic arch Interrupted aortic arch has a strong association with DiGeorge syndrome The presentation and diagnostic evaluation are covered together, with emphasis on the use of echocardiography both prenatally and postnatally, as well as cross-sectional imaging The operative approach and outcomes are discussed individually, although there is some overlap in technique as well as long-term sequelae, such as hypertension Percutaneous intervention is also reviewed, as it is most beneficial in recurrent obstruction and older populations Keywords Aortic arch anomalies; aortic coarctation; interrupted aortic arch; aortic isthmus; end-to-end anastomosis; end-to-side anastomosis; balloon stent angioplasty; aortic arch advancement; DiGeorge syndrome Introduction Coarctation derives from the Latin term coartatio, which translated literally means “a drawing together.” Aortic coarctation, therefore, indicates a narrowing at some point along the course of the aorta When used in the context of the congenitally malformed heart, coarctation most usually described an area of narrowing of the thoracic aorta in the region of the insertion of the arterial duct, with or without additional abnormalities of the aortic arch Obstructive lesions can be found more proximally, involving the ascending aorta These are considered, along with lesions of the aortic valve, in Chapter 45 Those distal to the thoracic aorta, together with acquired lesions, are beyond the scope of this chapter Within this chapter, however, interruption of the aortic arch is considered This involves discontinuity between two adjacent segments of the aortic arch In hemodynamic terms, it includes cases with a fibrous cord between the discontinuous segments In this respect, interruption can be interpreted as the extreme end of the spectrum of obstruction of the aorta (Fig 45.1) FIG 45.1 Morphologic spectrum of obstruction in the aortic arch, extending from the shelf lesion producing coarctation in the middle panel and moving in counterclockwise fashion to interruption of the aortic arch at the isthmus