Author: Anna Hartzog MD– Children’s National Hospital, Chinwe Unegbu MD – Children’s National Hospital


An 8-day-old, full term neonate with dextro-Transposition of the Great Arteries (d-TGA), aortic coarctation, ventricular septal defect (VSD), and a left circumflex coronary artery arising from a right coronary artery with an intramural course is now status post arterial switch operation, arch reconstruction, and VSD closure. In this patient, which of the following associated anomalies is the MOST LIKELY factor contributing to an increased risk of myocardial ischemia in the post-operative period?