Interrupted aortic arch abnormal aortic arch morphology interrupted aortic arch Fyler:1250 IAA complete discontinuation between the ascending and descending aorta; includes Type A, interruption distal to the subclavian artery that is ipsilateral to the second carotid artery, and Type B, interruption between second carotid artery and ipsilateral subclavian artery MP:0004157 MPheno.ontology interrupted aorta interrupted aortic arch