Institution: | 1. Department of Ultrasound, South Hospital District of Affiliated Hospital of Chengde Medical College, Chengde, China;2. Department of Echocardiography, Beijing Anzhen Hospital Affiliated Capital Medical University, Beijing, China;3. Department of Radiology, Beijing Anzhen Hospital Affiliated Capital Medical University, Beijing, China;4. Deaprtment of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden |