title: Human embryonic cardiovascular function.
abstract: This review presents an overview of descriptive knowledge on human embryonic cardiovascular physiology mostly based on noninvasive assessment by Doppler ultrasonography. Our objective was to identify and analyze published studies on embryonic cardiovascular function, and summarize available knowledge in this field.
  
  
  
  Citations related to human embryonic cardiovascular function were searched in PubMed, EMBASE, CINAHL and Web of Science using keywords and MeSH terms without any time limitation. The search was restricted to English language articles. Abstracts were screened and full texts of relevant articles were obtained. All articles that reported on physiological aspects of human embryonic cardiovascular function were included. Studies reporting on cardiovascular function after 10 weeks of gestation were excluded. Data were synthesized and presented narratively.
  
  
  
  We identified 10 studies that had evaluated cardiovascular function and/or hemodynamics in human embryos at ≤10 weeks of gestation. All of these reported only certain aspects of embryonic cardiovascular function. Embryonic heart rate is associated significantly with gestational age and increases from 6 to 10 weeks of gestation. Cardiac inflow is monophasic during the embryonic period and atria appear to generate higher force during contraction compared with ventricles. Both ventricular inflow and outflow velocities increase with advancing gestation, whereas the Tei index decreases significantly. During the embryonic period, placental blood flow increases with gestation, but absent umbilical artery diastolic flow and umbilical venous pulsations are normal phenomena.
  
  
  
  There are important differences in normal cardiovascular function between the embryonic and fetal stages of human in utero development.
authors.affiliation: Women's Health and Perinatology Research Group, Department of Clinical Medicine, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway.|Department of Obstetrics and Gynecology, University Hospital of Northern Norway, Tromsø, Norway.|Department of Clinical Sciences, Intervention and Technology, Karolinska Institute, Stockholm, Sweden.
authors.forename: Ganesh
authors.identifier: 0000-0002-1997-3107
authors.initials: G
authors.lastname: Acharya
authors.affiliation: Cardiovascular Center, Fudan University Children's Hospital, Shanghai, China.
authors.forename: Yonghao
authors.identifier: 0000-0002-5043-5534
authors.initials: Y
authors.lastname: Gui
authors.affiliation: Clinical Department of Obstetrics and Gynecology, Chair of Women's Health, School of Health Sciences, Medical University of Silesia, Katowice, Poland.
authors.forename: Wojciech
authors.identifier: 0000-0002-6437-8411
authors.initials: W
authors.lastname: Cnota
authors.affiliation: Perinatal Cardiology, All Children's Hospital, Pediatrix Medical Group, St Petersburg, Florida, USA.
authors.forename: James
authors.identifier: 0000-0002-3291-534X
authors.initials: J
authors.lastname: Huhta
authors.affiliation: Clinical Department of Obstetrics and Gynecology, Chair of Women's Health, School of Health Sciences, Medical University of Silesia, Katowice, Poland.
authors.forename: Agata
authors.identifier: 0000-0001-9811-9912
authors.initials: A
authors.lastname: Wloch
mesh_terms: D001783:Blood Flow Velocity; D005865:Gestational Age; D006439:Hemodynamics; D006801:Humans; D010920:Placenta; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries; D014680:Veins
keywords: Doppler; Human embryo; cardiac function; embryonic circulation; embryonic heart