[1] Univ Vermont, Larner Coll Med Univ Vermont, Dept Pediat,Childrens Hosp, Div Pediat Cardiol, 111 Colchester Ave, Burlington, VT 05401 USA
[2] Univ Connecticut Sch Med, Connecticut Childrens Med Ctr, Dept Pediat, Div Hematol Oncol, Hartford, CT USA
[3] Harvard Med Sch, Boston Childrens Hosp, Dept Cardiol, Dept Pediat, Boston, MA USA
[4] Maine Med Ctr, Dept Pediat, Div Pediat Cardiol, Portland, ME USA
[5] Geisel Sch Med Dartmouth, Dept Pediat, Div Pediat Cardiol, Hanover, NH USA
[6] Yale Sch Med, Dept Pediat, Sect Pediat Cardiol, New Haven, CT USA
[7] St Christophers Hosp Children, Div Pediat Cardiol, Philadelphia, PA USA
[8] Harvard Med Sch, Massachusetts Gen Hosp, Dept Pediat, Div Pediat Cardiol, Boston, MA USA
[9] Univ Massachusetts, Chan Med Sch, Dept Pediat, Div Pulmonol, Worcester, MA USA
[10] Northern Light Eastern Maine Med Ctr, Pediat Cardiol, Bangor, ME USA
[11] Brown Univ, Hasbro Childrens Hosp, Dept Pediat,Warren Alpert Med Sch, Dept Pediat, Providence, RI 02912 USA