[1] Univ Zurich Hosp, CH-8091 Zurich, Switzerland
[2] ISHLT Thorac Transplant Registry, Dallas, TX USA
[3] Childrens Hosp Philadelphia, Philadelphia, PA 19104 USA
[4] Washington Univ, Sch Med, St Louis, MO USA
[5] Univ Utah Hlth Care, Salt Lake City, UT USA