[1] Univ Penn, Perelman Sch Med, Dept Pediat, Philadelphia, PA USA
[2] Childrens Hosp Philadelphia, Div Cardiol, 3401 Civ Ctr Blvd,8NW49, Philadelphia, PA 19104 USA
[3] Childrens Hosp Philadelphia, Echocardiog Lab Res Unit, Philadelphia, PA USA
[4] Childrens Hosp Philadelphia, Ctr Fetal Diag & Treatment, Philadelphia, PA USA
[5] Childrens Hosp Philadelphia, Div Neonatol, Philadelphia, PA USA
[6] Univ Penn, Childrens Hosp Philadelphia, Dept Pediat Gen Thorac & Fetal Surg, Perelman Sch Med, Philadelphia, PA USA