1. Department of Medicine, Soochow University, Suzhou, Jiangsu 215123, P.R. China
2. Department of Cardiology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
3. Department of General Practice, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
4. Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, Liaoning 110016, P.R. China