1. Department of Cardiology IV, Cangzhou Central Hospital, Cangzhou, 061001 Hebei Province, China
2. Department of Cardiology II, Cangzhou Central Hospital, Cangzhou, 061001 Hebei Province, China
3. Department of Gynecology and Obstetrics, Cangzhou Peace Hospital, Cangzhou, 061001 Hebei Province, China