The purpose of this study is to track post-discharge outcomes on prematurely born infants who are discharged from the NICU with a patent ductus arteriosus (PDA). Investigators plan to report on the spontaneous closure rate as well as the incidence of pulmonary and/or cardiac events in these infants. The goal is to identify risk factors associated with adverse outcomes in prematurely born infants who are sent home with a PDA.