^○Silin Pan¹, Gang Luo¹, Kuiliang Wang¹, Yue Sun², Taotao Chen³ (1.Heart Center, Qingdao Women and Children’s Hospital, Qingdao University, China, 2.Fetal Medicine Unit, Qingdao Women and Children’s Hospital, Qingdao University, 3.Department of Obstetric Ultrasound, Qingdao Women and Children’s Hospital, Qingdao University)