1 Institute of Cardiovascular disease, China Three Gorges University, Yichang 443003, Hubei province, China; Department of Cardiology, Yichang Central People's Hospital, Yichang 443003, Hubei province, China.
2 Institute of Cardiovascular disease, China Three Gorges University, Yichang 443003, Hubei province, China; Department of Cardiology, Yichang Central People's Hospital, Yichang 443003, Hubei province, China. Electronic address: wuhui@ctgu.edu.cn.