Table of ContentsView AllTable of ContentsAnatomyFunctionAssociated ConditionsSummary
Table of ContentsView All
View All
Table of Contents
Anatomy
Function
Associated Conditions
Summary
The inferiorvena cava(also known as IVC or the posterior vena cava) is a large vein that carries oxygen-depleted blood from the torso and lower body to the right side of the heart. From there the blood ispumped to the lungsto get oxygen before going to the left side of the heart to be pumped back out to the body.
The IVC gets its name from its structure and location. It is the lower, or inferior, part of the vena cava—a large vein also made up of thesuperior vena cavathat carries blood from the head, neck, arms, and chest in the upper body to the heart.
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How big is the inferior vena cava?The IVC is one of the largest veins in the body, carrying a large volume of blood. It is about four inches long and almost 1 inch in diameter.
How big is the inferior vena cava?
The IVC is one of the largest veins in the body, carrying a large volume of blood. It is about four inches long and almost 1 inch in diameter.
Structure
The IVC goes from the diaphragm into the right side of the heart, beneath the entrance of the superior vena cava.
A few veins merge and drain into the IVC before it makes its way up to the heart:
This makes the IVC almost symmetrical. Other veins that enter the IVC include the hepatic veins, inferior phrenic veins, and lumbar vertebral veins.
Absence of Valves
What makes the IVC different from other veins is that there are no valves within this vein to keep blood moving forward instead of backward. To prevent blood from moving back into the body, other veins have valves that close as the blood flows past them.
Blood is pulled forward from the IVC all the way up to the heart due to the contraction of the diaphragm as the lungs fill with air.
The IVC’s job is to return blood to the heart from the lower half of the body, including the feet, legs, thighs, pelvis, and abdomen.
Location
The IVC starts in the lower back where the right and left common iliac veins (two major leg veins) have joined together. It runs under the abdominal cavity along the right side of the spinal column and enters the right atrium of the heart from the back of the heart.
From here, blood will pump out to the lungs for oxygen supply before traveling to the left side of the heart to be carried out to the body once again.
Anatomical Variations
There are some congenital (at birth) variations in IVC structure, and these are difficult to detect.Often a person won’t have any symptoms to signal a defect in the IVC. Symptoms, when they do occur, can include vague low back or abdominal pain.
Some variations of the IVC include the following:
The primary function of the IVC is to carry deoxygenated blood that has circulated through the lower half of the body back to the right atrium of the heart. The IVC is responsible for returning all of the blood below thediaphragm, while the superior vena cava returns the blood above the diaphragm to the heart.
Some conditions can also cause a dilated inferior vena cava, which can be serious. A dilated IVC may be a marker of poor heart function, blood flow abnormalities, and lower survival rates.
The inferior vena cava is one of two parts that make up the vena cava. The IVC carries blood from the legs, feet, and organs in the abdomen and pelvis to the right side of the heart. The IVC starts in the lower back and runs under the abdominal cavity along the right side of the spinal column and enters the right atrium of the heart.
7 Sources
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Kim SS, Shin HC, Hwang JA, et al.Various congenital anomalies of the inferior vena cava: review of cross-sectional imaging findings and report of a new variant. Abdom Radiol (NY). 2018;43(8):2130-2149. doi:10.1007/s00261-017-1430-y
Petik B.Inferior vena cava anomalies and variations: imaging and rare clinical findings. Insights Imaging. 2015;6(6):631-9. doi:10.1007/s13244-015-0431-z
Rajabnejad Y, Aliakbarian M, Rajabnejad A, Motie MR.Left-Sided Inferior Vena Cava Encountered During Organ Retrieval Surgery: Report of Two Cases. Int J Organ Transplant Med. 2016;7(4):229-232.
Shammas NW, Rachwan RJ, Daher G, Bou dargham B.Double Inferior Vena Cava and its Implications During Endovascular and Surgical Interventions: A Word of Caution. J Invasive Cardiol. 2017;29(2):51-53.
Lawrensia S, Khan YS.Inferior Vena Cava Syndrome. [Updated 2023 May 20]. In: StatPearls [Internet].
Garcia‐Montilla R, Mukundan S, Heitner SB, et al.Inferior vena cava dilation predicts global cardiac dysfunction in acute respiratory distress syndrome: A strain echocardiographic study. Echocardiography. 2021;38(2):238-248. doi: 10.1111/echo.14970
Inferior Vena Cava. Innerbody website. Updated December 2016.Inferior Vena Cava. Kenhub GmbH website.Inferior Vena Cava Filter Placement and Removal. Radiologyinfo.org website. Updated April 2018.Tucker, William D. Burns, Bracken.Anatomy, Abdomen and Pelvis, Inferior Vena Cava.: Treasure Island, FL: StatPearls Publishing; 2019.
Inferior Vena Cava. Innerbody website. Updated December 2016.
Inferior Vena Cava. Kenhub GmbH website.
Inferior Vena Cava Filter Placement and Removal. Radiologyinfo.org website. Updated April 2018.
Tucker, William D. Burns, Bracken.Anatomy, Abdomen and Pelvis, Inferior Vena Cava.: Treasure Island, FL: StatPearls Publishing; 2019.
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