1. Department of Medicine, HeartOtago, Dunedin School of Medicine, University of Otago , PO Box 9056, Dunedin 9054 , New Zealand
2. Department of Surgical Sciences, Dunedin School of Medicine, University of Otago , Dunedin , New Zealand
3. St Thomas’ Hospital and Cleveland Clinic London , UK
4. Department of Cardiology, Dunedin Hospital, Te Whatu Ora Southern , 201 Great King Street, Dunedin 9016 , New Zealand