1. Department of Cardiology, Life Fourways Hospital, Johannesburg, South Africa
2. School of Health Sciences, University of Witwatersrand, Johannesburg, South Africa
3. Department of Cardiothoracic Surgery, Ethekweni Heart Centre and Busamed Gateway Private Hospital, Durban, South Africa
4. Department of Cardiothoracic Surgery, Olivedale Clinic, Johannesburg, South Africa
5. Department of Anesthesiology, Morningside Medi-Clinic, Johannesburg, South Africa