[1] Med Univ S Carolina, Dept Pediat, Div Cardiol, Charleston, SC 29425 USA
[2] New England Res Inst, Watertown, MA 02172 USA
[3] Univ Toronto, Hosp Sick Children, Dept Pediat, Div Cardiol, Toronto, ON M5G 1X8, Canada
[4] Univ Texas Southwestern, Dept Pediat, Dallas, TX USA
[5] Childrens Hosp Philadelphia, Div Cardiol, Philadelphia, PA 19104 USA
[6] Univ Utah, Dept Surg, Salt Lake City, UT USA
[7] Childrens Hosp, Dept Cardiol, Boston, MA 02115 USA
[8] NHLBI, NIH, Bethesda, MD 20892 USA
[9] Duke Univ, Med Ctr, Dept Pediat, Durham, NC 27710 USA
[10] Columbia Univ, Div Pediat, Med Ctr, New York, NY USA