1. Department of Cardiology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
2. Department of Cardiology, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi 533000, P.R. China
3. Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, UK