Page 71 - Virtual Vascular Vol 11
P. 71
Embryological development of the Inferior vena cava is complex.
A series of successive venous networks take part in the formation of the
inferior vena cava. Each predominates temporarily, then regresses, and
remains only partly in the final definitive system.
At 4 weeks of life, 3 distinct venous systems have already been developed:
• the vitelline system drains the gut,
• the umbilical system drains the placenta,
• The cardinal system drains the rest of the embryo.
The infrahepatic IVC develops from a set of 3 paired parallel veins appearing
consecutively between 4 and 8 weeks of life, namely the posterior cardinal,
subcardinal and supra cardinal veins.
The suprahepatic IVC is derived from the cranial segment of the right
vitelline vein. The retro-hepatic segment is derived from an anastomosis
between the cranial segment of the right subcardinal vein and the right
vitelline vein.
The infra-hepatic/supra-renal IVC is derived from the right subcardinal vein.
The renal collar is formed from anastomoses between the supra cardinal
veins posteriorly and the subcardinal veins anteriorly, with the posterior
limb regressing during development. On the right, the anterior limb is
incorporated into the lateral wall of the renal segment of the IVC; and on
the left, the anterior limb forms the normal adult left renal vein.
The suprarenal portions of the right and left supra cardinal veins connect
with the posterior cardinal veins, forming the azygos and hemiazygos
systems, respectively. The infrarenal portions disappear on the left but form
the infrarenal portion of the IVC on the right. The posterior cardinal veins
mostly regress except for the distal portion, which later become the iliac
confluence and future iliac veins, and the proximal portion, which joins the
azygos and the hemiazygos veins.
In this patient, the infrarenal portion persisted on the left but disappeared
on the right. This is a very rare anomaly.
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Ghandour A. et al. Cardiovascular Diagnosis & Therapy 2016; 6: 482–492.
