Crossed pulmonary arteries with hypoplasia of the transverse aortic arch.

BACKGROUND The entity of crossed pulmonary arteries was first described by Jue, Lockman, and Edwards in 1966, in a patient with trisomy 18. Since then, several series have been described, both in terms of the isolated anatomic variant, or its association with other intracardiac or extracardiac anomalies. We describe a rare association that has previously not been reported. Methods and results Institutional Review Board approval for a retrospective chart review was obtained. Over the period 2011 through 2013, we have encountered six patients in whom the crossed origins of the pulmonary arteries from the pulmonary trunk were associated with hypoplasia of the transverse aortic arch, an association that, to the best of our knowledge, has previously not been reported. In all of the patients, the isthmic component of the aortic arch was inserted in an end-to-side manner into the ductal arch, with additional discrete coarctation in half of the patients. CONCLUSION To the best of our knowledge, no cases of crossed pulmonary arteries have been described in association with hypoplasia of the transverse aortic arch. We draw comparisons between the cases with exclusively tubular hypoplasia, and those with the added problem of the more typical isthmic variant of aortic coarctation. In all cases, the ability to reconstruct cross-sectional images added significantly to the diagnosis and understanding of these complex lesions. These findings have specific surgical implications, which are discussed.