1 Fetal and Neonatal Cardiology Program, Echocardiography Laboratory, Division of Cardiology, Department of Pediatrics, University of Alberta, Edmonton, Canada (L.G.E., L.K.H.).
2 Department of Obstetrics and Gynecology, Women and Children's Health Research, Mazankowski Alberta Heart Institutes, University of Alberta, Edmonton, Canada (L.K.H.).