1. Division of Cardiovascular Surgery, Hospital of the University of Pennsylvania, Philadelphia (M.K., P.V., W.Y.S., J.E.B., N.D.D.).
2. Department of Cardiovascular Surgery, Heart Center Freiburg University, Faculty of Medicine, University of Freiburg, Germany (M.K., B.R., M.C., F.B.).
3. Department of Cardiovascular Surgery, Jichi Medical University, Saitama Medical Centre, Japan (R.I., H.O., N.K., A.Y.).