1. Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong 264000, P.R. China
2. Department of Cardiovascular Catheterization Exam, Yantai Yuhuangding Hospital, Yantai, Shandong 264000, P.R. China
3. Department of Physical Examination, Yantai Yuhuangding Hospital, Yantai, Shandong 264000, P.R. China