Anomalous origin of the left pulmonary artery from the ascending aorta in two children with pulmonary atresia, sub-aortic ventricular septal defect and right-sided major aorto-pulmonary collateral arteries

摘要

We report two rare cases of an anomalous origin of the leftpulmonary artery (AOLPA) from the ascending aorta, associatedwith pulmonary atresia, a ventricular septal defectand a left aortic arch. The cases are unusual because AOLPAis more commonly associated with a right aortic arch andit is more usual for the right pulmonary artery to originateanomalously from the ascending aorta. The pulmonaryblood supply to the right lung in both patients was absentand provided instead by major aorto-pulmonary collateralarteries which were stenosed at multiple levels. The AOLPAin both patients originated from the postero-lateral aspect ofthe ascending aorta just distal to the sino-tubular junction.Only one patient showed the more common association ofan unusual aortic arch branching pattern in the form of ananomalous right subclavian artery.Neither patient was in heart failure and the chest X-rayin both revealed differential pulmonary perfusion withprominent vascularity of the left lung. Cardiac catheterisationshowed systemic pressures within the anomalous leftpulmonary artery. Karyotyping revealed normal chromosomes,and fluorescent in-situ hybridisation done in onepatient was negative for chromosome 22q11.2 microdeletion.Both patients have been managed conservatively.