Since 2012, there has been growing use of the HeartWare (Medtronic, Mounds View, MN) intracorporeal continuous flow (CF) ventricular assist device (VAD) in children, despite it not being labeled for use in pediatric patients. We sought to describe the use and outcomes of children with HeartWare VADs.We identified all patients aged19 years and young adults aged 19 to 30 years supported with HeartWare who were entered into the pediatric portion (Pedimacs) of the Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) and the Intermacs registries, respectively, between September 2012 and June 2017. Adverse events and outcomes were analyzed and compared.We identified 192 children and 247 young adult HeartWare patients. Baseline characteristics of children differed from young adults, with lower median weight of 51.5 kg (range, 13.1-162) vs 75.8 kg (range, 29.8-191; p ≤ 0.0001) and body surface area of 1.5 mSurvival in children supported with HeartWare is encouraging and comparable to young adults; however, adverse events are not uncommon in children. Ongoing evaluation of the HeartWare use in children is necessary to further decrease the rate of adverse events and understand obstacles to discharge.