[1] Wayne State Univ, Childrens Hosp Michigan, Detroit, MI 48202 USA
[2] Univ Calif San Francisco, Pediat, Pediat Echocardio, Pediat Cardiol, San Francisco, CA 94143 USA
[3] Stanford Univ, Pediat, Stanford, CA 94305 USA
[4] Lucile Packard Childrens Hosp, Pediat Pulm Hypertens Serv, Pulm Vasc Dis, Stanford, CA USA
[5] Boston Childrens Hosp, Cardiol, Program Pediat Cardiol & Cardiovasc Res, Boston, MA USA
[6] Harvard Univ, Sch Med, Pediat, Cambridge, MA 02138 USA
[7] Univ Nebraska, Pediat, Childrens Hosp & Med Ctr, Cardiol, Lincoln, NE 68583 USA
[8] Columbia Univ, Coll Phys & Surg, Div Chief Pediat Cardiol, New York, NY 10027 USA