1. Department of Internal Medicine, Hebei Medical University, Shijiazhuang, China (H.Z., Q.Z.).
2. Department of Cardiology, Tangshan Gongren Hospital Affiliated to Hebei Medical University, China (H.Z., X.L., G.Q., C.Y., Q.Z.).
3. Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, Hebei, China (S.W., S.C., Y.W., J.L.).