1. Department of Cardiology, Central Adelaide Local Health Network , Port Road, Adelaide, South Australia 5000 , Australia
2. Whyalla Hospital and Health Service , Wood Terrace, Whyalla, South Australia 5600 , Australia
3. Department of Cardiothoracic Surgery , Flinders Drive, Bedford Park, Adelaide, South Australia 5042 , Australia
4. College of Medicine and Public Health, Flinders University , Sturt Road, Bedford Park, South Australia 5042 , Australia
5. Department of Cardiology, Southern Adelaide Local Health Network , Flinders Drive, Bedford Park, Adelaide, South Australia 5042 , Australia