[1] Northwestern Univ, Childrens Mem Hosp, Dept Surg,Sch Med, Div Cardiovasc Thorac Surg, Chicago, IL 60614 USA
[2] Mem Hosp Warsaw, Childs Hlth Ctr, Warsaw, Poland
[3] Univ Krankenhaus Eppendorf, Hamburg, Germany
[4] Hosp Sick Children, London WC1N 3JH, England
[5] Childrens Hosp Philadelphia, Div Pediat Cardiovasc Surg, Cardiac Ctr, Philadelphia, PA 19104 USA
[6] Univ S Florida, Div Thorac & Cardiovasc Surg, All Childrens Hosp, Coll Med, St Petersburg, FL 33701 USA
[7] St Christophers Hosp Children, Sect Cardiothorac Surg, Philadelphia, PA 19133 USA
[8] Montreal Childrens Hosp, Montreal, PQ H3H 1P3, Canada
[9] Jikei Univ, Sch Med, Tokyo, Japan