Case Report
We present the case of a 2,770 gram baby girl born at 37 weeks and 2 days with a prenatal diagnosis of d-TGA with intact ventricular septum who was initially brought to the neonatal intensive care unit on prostaglandin. She was then quickly taken for a cardiac catheterization for a balloon atrial septostomy. TTE confirmed the prenatal diagnosis of d-TGA with intact ventricular septum and also showed a large left patent ductus arteriosus (PDA) with bidirectional shunting. Aortic arch imaging suspected AORSA because of a lack of bifurcation of the first right brachiocephalic branch, although its origin was not visualized. Her body appeared cyanotic and dusky with sparing of the right hemithorax and arm. Pre-ductal oxygen saturation on the right hand was consistently above 90% whereas the post-ductal oxygen saturations on all other extremities were 60 – 70%. Interestingly, when the pre-ductal pulse oximeter was moved to the right ear, the oxygen saturation dropped to resemble the post-ductal levels. This prompted for systematic evaluation for the origin of the right subclavian artery from the pulmonary artery system, in the setting of transposition physiology. Repeat TTE confirmed prior findings and clearly demonstrated the right subclavian artery from the proximal RPA. Additional anatomic details included anomalous origin of the left coronary artery from the right sinus and an isolated cleft of the mitral valve that was diagnosed on fetal imaging. On day of life 13, the patient underwent an arterial switch operation (ASO) with LeCompte maneuver, single coronary button with creation of a neo-aortic to coronary hood, closure of atrial septal defect, and ligation of the left-sided PDA. The preoperative echocardiographic diagnosis of AORSA from the proximal RPA was confirmed (Figure 1). The anomalous vessel was ligated and divided from the RPA. She had an uncomplicated post-operative course.