['To describe patent ductus arteriosus (PDA) stenting regardless of ductal morphology in high risk patients with hypoplast physiology undergoing hybrid stage I palliation (PDA stenting and placement of bilateral pulmonary artery bands).', 'Hybrid palliation is an accepted alternative for patients with hypoplastic left heart syndrome. Patients weighing less than 2.5 kg, history of prematurity, intracranial hemorrhage, and chromosomal abnormality belong to a high-risk group who otherwise might not be ideal candidates for traditional surgical repair (Norwood Operation).', 'Between May 2005 and February 2013, a series of 13 high-risk patients with hypoplast physiology with varying types of ductal morphology underwent PDA stenting as part of hybrid stage I palliation.', 'Three major types of ductal morphology were identified: (1) short and semi horizontal, (2) long and semi horizontal, and (3) tortuous. All patients underwent successful PDA stenting. One patient developed proximal coarctation from inadequate coverage of the pulmonary end of the PDA and was successfully treated with a balloon expandable stent 69 days after the initial procedure.'] Does morphology of the patent ductus arteriosus preclude successful patent ductus arteriosus stent implantation in high-risk patients undergoing hybrid stage I palliation : recommendations to optimize ductal stent positioning?