This case report describes the management of a large iatrogenic ventricular septal defect (VSD) created by the coring device during systemic ventricular assist device (RVAD) insertion in a 16 year-old patient with congenitally corrected transposition of the great arteries. The VSD was closed by bovine pericardial patch and the ventriculotomy was extended laterally to relocate the VAD sewing ring. After RVAD implantation, patient initially remained cyanotic, potentially due to a tiny VSD patch leak with right to left shunting. Hypoxia was successfully corrected by rescue nitric oxide infusion and patient was bridged to transplant after 91 days.