View source for Ductus venosus

{{Short description|Vein in the human fetus}}
{{Infobox vein
| Name        = ''Ductus venosus''
| Latin       = ductus venosus
| Image       = Gray502.png
| Caption     = [[Fetal circulation]]. The ''ductus venosus'' (red) connects the [[umbilical vein]] to the ''[[inferior vena cava]]''.
| Image2      = Gray475.png
| Caption2    = The [[liver]] and the veins in connection with it, of a human embryo, twenty-four or twenty-five days old, as seen from the ventral surface.
| DrainsFrom  =
| Source      = [[Umbilical vein]]
| DrainsTo    = [[Inferior vena cava]]
| Artery      = [[Ductus arteriosus]]
}}
In the [[fetus]], the '''''ductus venosus''''' (''"DV"''; '''Arantius' duct''' after [[Julius Caesar Aranzi]]<ref>{{cite web |url=http://www.whonamedit.com/synd.cfm/243.html |title=Whonamedit - dictionary of medical eponyms |website=www.whonamedit.com}}</ref>) shunts a portion of [[umbilical vein]] blood flow directly to the [[inferior vena cava]].<ref>{{Cite journal |doi = 10.1016/S0002-9378(00)70504-7 |last1 = Kiserud |first1 = T. |last2 = Rasmussen |first2 = S. |last3 = Skulstad |first3 = S. |title = Blood flow and the degree of shunting through the ductus venosus in the human fetus |journal = American Journal of Obstetrics and Gynecology |volume = 182 |issue = 1 Pt 1 |pages = 147–153 |year = 2000 |pmid = 10649170}}</ref> Thus, it allows oxygenated blood from the [[placenta]] to bypass the [[liver]].  Compared to the 50% shunting of umbilical blood through the ''ductus venosus'' found in animal experiments, the degree of shunting in the human fetus under physiological conditions is considerably less, 30% at 20 weeks, which decreases to 18% at 32 weeks, suggesting a higher priority of the fetal liver than previously realized.<ref>{{cite journal |last1=Kiserud |first1=T |title=Fetal venous circulation -- an update on hemodynamics |journal=J Perinat Med |date=2000 |volume=28 |issue=2 |pages=90–6 |pmid=10875092 |doi=10.1515/JPM.2000.011 |s2cid=11799576}}</ref> In conjunction with the other fetal shunts, the [[Foramen ovale (heart)|''foramen ovale'']] and ''[[ductus arteriosus]]'', it plays a critical role in preferentially shunting oxygenated blood to the fetal brain. It is a part of [[fetal circulation]].

==Anatomic course==
The pathway of fetal umbilical venous flow is

umbilical vein <math>\rightarrow</math> left portal vein  <math>\rightarrow</math> ''ductus venosus''  <math>\rightarrow</math> ''inferior vena cava''  <math>\rightarrow</math> eventually right atrium.

This anatomic course is important to recall when assessing the success of neonatal umbilical venous catheterization, as failure to cannulate through the ''ductus venosus'' results in malpositioned hepatic catheterization via the left or right portal veins. Complications of such positioning can include hepatic hematoma or abscess.

==Postnatal closure==
The ''ductus venosus'' is open at the time of birth, and that is the reason why a catheter inserted into the umbilical vein (umbilical vein [[catheterization]] / "UVC") can reach the inferior vena cava; absent a patent ''DV'', such a catheter would continue into the portal vein. The ''ductus venosus'' naturally closes during the first week of life in most full-term neonates; however, it may take much longer to close in pre-term neonates. Functional closure occurs within minutes of birth. Structural closure in term babies occurs within 3 to 7 days.

After the ''ductus venosus'' closes, its remnant is known as ''[[ligamentum venosum]]''.

{{Anchor|Patent ductus venosus}} If the ''ductus venosus'' fails to occlude after birth, it remains patent (open), and the individual is said to have a patent ''ductus venosus'' and thus an intrahepatic [[portosystemic shunt]] (PSS).<ref name="omim_601466">{{Citation |author=Online Mendelian Inheritance in Man |author-link=Online Mendelian Inheritance in Man |title=Patent ductus venosus; PDV |url=http://www.omim.org/entry/601466 |postscript=.}}</ref> This condition is hereditary in some dog breeds (e.g. [[Irish Wolfhound]]). The ''ductus venosus'' shows a delayed closure in [[preterm infant]]s, with no significant correlation to the closure of the ''[[ductus arteriosus]]'' or the condition of the infant.<ref name=Fugelseth>{{cite journal |vauthors=Fugelseth D, Lindemann R, Liestøl K, Kiserud T, Langslet A |title=Postnatal closure of ductus venosus in preterm infants ≤32 weeks. An ultrasonographic study |journal=Early Hum. Dev. |volume=53 |issue=2 |pages=163–9 |date=December 1998 |pmid=10195709 |doi= 10.1016/s0378-3782(98)00051-6}}</ref> Possibly, increased levels of dilating prostaglandins leads to a delayed occlusion of the vessel.<ref name=Fugelseth/>
[[File:Agenesis of ductus venosus human.jpg|thumb|left|600px|Agenesis of ductus venosus (ADV) in a first trimester case with umbilical vein drainage into inferior vena cava (IVC) and increased nuchal translucency. (A): Transverse plane of the FT fetal abdomen, with high-definition directional power Doppler applied. An ”H”-shaped variant of the intrahepatic portal veins connection is identified; (B): high-definition directional power Doppler in the sagittal plane of the fetal abdomen (same case) showing ADV with umbilical vein drainage into the inferior vena cava; (C): mid-sagittal view of the fetal face with the measurement of the thickened NT. MPV main portal vein, St stomach, LPV left portal vein, UV umbilical vein, RPVa anterior branch of right portal vein, RPVp posterior branch of right portal vein, Ao aorta, IVC inferior vena cava, ADV ductus venosus agenesis, P palate, NB nasal bone, NT nuchal translucency.]]

==References==
{{reflist}}

{{Development of circulatory system}}
{{Veins}}

[[Category:Embryology of cardiovascular system]]
[[Category:Veins]]