1. From the Department of Cardiac and Thoracic Vascular Surgery (T.H., U.S., M.F.B., A.E., .M., H.H.S.), University of Luebeck, Germany (Registry Site); Sana Herzchirurgische Klinik Stuttgart (J.O.B., W.H., J.G.R.), Stuttgart, Germany; Herzzentrum Bodensee (C.A.B.), Konstanz, Germany; the Department of Mathematics (D.R.R.), School of Science and Technology, University of Sussex, Brighton, UK; the German Heart Center (R.L., J.H.), Munich, Germany; Johann-Wolfgang-Goethe-University (A.M., F.O.),...