Duplicated left pulmonary artery: an unknown disease? Three case reports and review of the literature.

We report three cases of an abnormal finding of duplicated left pulmonary artery: two of these occurring in children with Kabuki syndrome and configuring the setting of a pseudo-pulmonary sling without any clinical or cardiac cross-sectional evidence of tracheal compression. The other case instead represents duplicated left pulmonary artery with pulmonary sling caused by the retro-tracheal course of the lower left pulmonary artery associated with "Christmas Tree" arrangement of the tracheo-bronchial system. In both patients with pseudo-pulmonary sling and Kabuki syndrome, the abnormal finding was incidental during echocardiographic examination and neither of the patients required surgical repair for the condition. To the best of our knowledge, they represent the third and fourth cases in which such an anomaly of the pulmonary artery branches not forming a sling is seen in association with Kabuki syndrome. Another case represents our second experience and the second case reported in literature with duplicated left pulmonary artery in the setting of a complex tracheal anatomy. In this symptomatic patient, surgical repair of atrial septal defect and relief of the vascular ring were indicated, and the surgical repair was performed successfully at the age of 3 years.