1 Cardiovascular Research Unit, Cape Heart Institute, University of Cape Town, Cape Town, South Africa; Chris Barnard Division of Cardiothoracic Surgery, University of Cape Town, Cape Town, South Africa; Groote Schuur Hospital, Cape Town, South Africa. Electronic address: Peter.Zilla@uct.ac.za.
2 Wake Forest Institute of Regenerative Medicine, Winston Salem, North Carolina, USA.
3 Cardiovascular Research Unit, Cape Heart Institute, University of Cape Town, Cape Town, South Africa.