University of Cambridge - Cambridge Biomedical Campus, University of Cambridge - Cambridge Biomedical Campus, Vanderbilt Heart Transplant Unit, Vanderbilt Heart Transplant Unit, Vanderbilt Heart Transplant Unit, Spanish Registry on Heart Transplantation, Hospital Universitario Virgen de la Arrixaca, Hospital Universitario Virgen de la Arrixaca, NYU Langone - Department of Cardiothoracic Surgery., NYU Langone - Department of Cardiothoracic Surgery., NYU Langone - Department of Cardiothoracic Surgery., NYU Langone - Department of Cardiothoracic Surgery., KU Leuven - Department of Cardiac Surgery, KU Leuven - Department of Cardiac Surgery, KU Leuven - Department of Cardiac Surgery, Centre Hospitalier Universitaire de Liege - Department of Cardiovascular Surgery, University of Nebraska at Omaha - Department of Cardiothoracic Surgery, NHS-BT 500, NHS Foundation Trust - Royal Papworth Hospital, Golden Jubilee National Hospital and University of Cambridge - Cambridge Biomedical Campus