1. Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, Shandong 250014, P.R. China
2. Department of Cardiology, Jimo District Qingdao Hospital of Traditional Chinese Medicine, Qingdao, Shandong 266200, P.R. China
3. Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, Shandong 250014, P.R. China
4. Department of Cardiology, The First Affiliated Hospital of Shandong First Medical University, Jinan, Shandong 250014, P.R. China
5. Department of Geriatric Medicine, Tai'an City Central Hospital, Tai'an, Shandong 271000, P.R. China