1. Graduate School, Tianjin Medical University, Tianjin 300051, China
2. Department of Geriatrics, The First Hospital of Qinhuangdao, Qinhuangdao 066000, China
3. Department of Cardiology, Tianjin Chest Hospital, Tianjin Medical University, Xi’an Road No. 93, Heping District, Tianjin, 300051, China
4. Cardiology Department, Dagang Oil Field General Hospital, Tianjin Medical University, Tianjin 300051, China