Ze-Rui Zhao1, Calvin S H Ng2. 1. Division of Cardiothoracic Surgery, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China. 2. Division of Cardiothoracic Surgery, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China. Electronic address: calvinng@surgery.cuhk.edu.hk.