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The inferior vena cava (IVC) is the largest vein in the body, formed by the confluence of the right and left common iliac veins at the level of L5 vertebra, and it drains deoxygenated blood from the lower limbs, pelvis, and abdomen into the right atrium of the heart.
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| Course | • Ascends along the right side of the vertebral column. • Pierces the central tendon of the diaphragm at T8 (caval opening) to enter the right atrium. | | --- | --- | | Tributaries | 1. Common iliac veins (formation). 2. Lumbar veins (posterior abdominal wall). 3. Right gonadal vein (testicular/ovarian). 4. Renal veins (left renal vein receives left gonadal and left adrenal veins). 5. Right adrenal vein. 6. Hepatic veins (just below diaphragm). 7. Inferior phrenic veins. | | Relations | • Anterior: Duodenum (3rd part), pancreas head, portal vein, bile duct, liver. • Posterior: Right psoas muscle, right sympathetic trunk, right renal artery, right crus of diaphragm. |
The mature IVC is composed of infrarenal (right supracardinal vein), renal (right suprasubcardinal and intersubcardinal anastomoses), suprarenal (right subcardinal vein) and hepatic (vitelline veins) segments. Renal and suprarenal segments are separated by the dashed line. Posterior cardinal veins persist as paired common iliac veins which join to form the iliac confluence, whilst supracardinal veins contribute to the azygos venous system draining into the superior vena cava. The gonadal and suprarenal veins are derived from subcardinal veins
Li, S.J., Lee, J., Hall, J. et al. The inferior vena cava: anatomical variants and acquired pathologies. Insights Imaging 12, 123 (2021). https://doi.org/10.1186/s13244-021-01066-7
Complex development from posterior cardinal, subcardinal, and supracardinal veins.
Complete sequence of the embryogenesis of the inferior vena cava. Development of the IVC at a fourth week of gestation, b fifth week of gestation, c seventh week of gestation, d eighth week of gestation, and 32nd week of gestation. The final adult IVC is formed of four different segments: (i) the hepatic segment, (ii) the suprarenal segment, (iii) the renal segment, and (iv) the infrarenal segment (b). The cranial segment of the inferior vena cava forms when the left supracardinal veins regresses. This leaves the right subcardinal segment as the only channel connecting with the hepatocardiac venous contribution, which in turn joins the heart. The junction for the renal, adrenal, and gonadal veins is provided by the intersubcardinal anastomosis. The caudal portion of the inferior vena cava is derived from the right supracardinal segment. The common iliac veins are formed from the postcardinal veins through the persistence of the interpostcardinal anastomosis. The final adult configuration of the inferior vena cava (f) with its different branches
González, J., Gaynor, J.J., Albéniz, L.F. et al. Inferior Vena Cava System Anomalies: Surgical Implications. Curr Urol Rep 18, 10 (2017). https://doi.org/10.1007/s11934-017-0658-y
Embryological development of the IVC. a The sinus venosus receives paired common cardinal, umbilical and vitelline veins draining blood from general tissue, the placenta and the yolk sac, respectively. b The right hepatocardiac channel (purple) is formed by the right vitelline vein and persists to become the hepatic IVC. Paired subcardinal (red) and supracardinal veins (green) emerge and form multiple anastomotic channels. These include the intersubcardinal anastomoses, suprasubcardinal anastomoses and fusion between the right subcardinal vein (red) and developing hepatic IVC (purple). As the embryo matures, some of these anastomoses regress. c This illustration highlights vessels that persist to form the mature IVC and its tributaries
Li, S.J., Lee, J., Hall, J. et al. The inferior vena cava: anatomical variants and acquired pathologies. Insights Imaging 12, 123 (2021). https://doi.org/10.1186/s13244-021-01066-7
Explains congenital anomalies:
| USD | • Assess patency, diameter, thrombus. • Dynamic changes with respiration (collapse in hypovolemia). | | --- | --- | | CTV | • Excellent for delineating anatomy, anomalies, thrombosis, tumor extension. • Evaluate hepatic vein confluence, retrohepatic segment. | | Venography | Used for interventional planning (stenting, filter placement). |