1. Department of Electrocardiogram, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
2. Department of Cardiology, The First Hospital of China Medical University, Shenyang, China
3. Department of Cardiology, The First Affiliated Hospital, Zhejiang University School Of Medicine , Hangzhou, Zhejiang, China
4. Department of Cardiology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, Peoples R China