[1] Univ Calif Irvine, Dept Obstet & Gynecol, Orange, CA 92668 USA
[2] Univ Calif Irvine, Div Maternal Fetal Med, Orange, CA 92668 USA
[3] Massachusetts Gen Hosp, Dept Radiol, Div Cardiovasc Imaging, 32 Fruit St, Boston, MA 02114 USA
[4] Massachusetts Gen Hosp, Dept Med, Div Cardiol, Boston, MA 02114 USA