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Fig. 7. 2-month-old boy with heterotaxy, dextrocardia, visceral situs
inversus, single right ventricle, total pulmonary venous return to right
innominate vein, pulmonary atresia, left aortic arch with normal branching,
and bilateral ductus arteriosi supplying intrapulmonary right and left
pulmonary arteries with bilateral absent extrapulmonary portions. Right ductus
arteriosus originates from base of right innominate artery and left ductus
arteriosus from underside of arch. (same patient as in Fig.
4A,4B).
Diagram shows primitive (seventh fetal week) and final arch and pulmonary
artery anatomy. Roman numerals denote six (I-VI) primitive aortic arches and
seventh intersegmental artery (VII). Truncoaortic sac is depicted in dark
gray, ventral aorta in pink, dorsal aorta in light gray, intrapulmonary
pulmonary arteries in light blue, and primitive aortic arches: III in red, IV
in yellow, and VI in dark blue.