[1] Univ Calif San Diego, Dept Pediat, Rady Childrens Hosp, Div Cardiol, San Diego, CA 92103 USA
[2] Cincinnati Childrens Hosp, Dept Pediat, Div Cardiol, Cincinnati, OH USA
[3] Hosp Sick Children, Dept Pediat, Div Cardiol, Toronto, ON M5G 1X8, Canada
[4] Harvard Univ, Sch Med, Dept Pediat, Div Cardiol,Childrens Hosp Boston, Boston, MA 02115 USA
[5] Ohio State Univ, Nationwide Childrens Hosp, Dept Pediat, Div Cardiol, Columbus, OH 43210 USA
[6] Johns Hopkins Childrens Ctr, Dept Pediat, Div Cardiol, Baltimore, MD USA
[7] Univ Penn, Childrens Hosp Philadelphia, Perelman Sch Med, Dept Pediat,Div Cardiol, Philadelphia, PA 19104 USA
[8] Emory Univ, Sch Med, Dept Pediat, Div Cardiol,Childrens Healthcare Atlanta, Atlanta, GA USA
[9] George Washington Univ, Sch Med, Dept Pediat, Div Cardiol,Childrens Natl Med Ctr, Washington, DC 20052 USA