[1] Hannover Med Sch, Dept Cardio Thorac Transplant & Vasc Surg, Hannover, Germany
[2] Hosp Univ Penn, Div Cardiovasc Surg, Philadelphia, PA 19104 USA
[3] Univ Hosp Bern, Clin Cardiovasc Surg, CH-3010 Bern, Switzerland
[4] European Hosp, Dept Cardiac Surg, Rome, Italy
[5] St Orsola Marcello Malpighi Hosp, Dept Cardiac Surg, Bologna, Italy
[6] Heart Ctr Leipzig, Dept Cardiac Surg, Leipzig, Germany
[7] Hosp Hietzing, Dept Cardiovasc Surg, Vienna, Austria
[8] Med Univ Innsbruck, Dept Cardiac Surg, A-6020 Innsbruck, Austria
[9] Univ Essen Gesamthsch, West German Heart Ctr, Dept Thorac & Cardiovasc Surg, Essen, Germany
[10] Hosp Clin Barcelona, Dept Cardiovasc Surg, Barcelona, Spain
[11] Cleveland Clin, Inst Heart & Vasc, Abu Dhabi, U Arab Emirates
[12] Malmo Univ Hosp, Dept Vasc Surg, Malmo, Sweden
[13] Acad Hosp St Jan, Brugge, Belgium
[14] Cardiovasc Clin, Bad Neustadt an der Saale, Germany
[15] Univ Zurich Hosp, Dept Cardiovasc Surg, CH-8091 Zurich, Switzerland
[16] Univ Heart Ctr Freiburg Bad Krozingen, Freiburg, Germany