The inferior vena cava is a large vein that carries the deoxygenated

blood Blood is a body fluid Body fluids, bodily fluids, or biofluids are liquid A liquid is a nearly incompressible In fluid mechanics or more generally continuum mechanics, incompressible flow (isochoric process, isochoric flow) refers t ...

blood

from the lower and middle body into the

right atrium The atrium (Latin ātrium, “entry hall”) is the upper chamber through which blood enters the ventricles of the heart The heart is a cardiac muscle, muscular Organ (biology), organ in most animals, which pumps blood through the blood ...

of the

heart The heart is a muscular MUSCULAR (DS-200B), located in the United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain,Usage is mixed. The Guardian' and Telegraph' use ...

heart

. It is formed by the joining of the right and the left

common iliac vein In human anatomy, the common iliac veins are formed by the external iliac veins and internal iliac veins. The left and right common iliac veins come together in the abdomen at the level of the lumbar vertebrae, fifth lumbar vertebra, forming the ...

s, usually at the level of the fifth

lumbar vertebra The lumbar vertebrae are, in human anatomy, the five vertebrae between the Human rib cage, rib cage and the Human pelvis, pelvis. They are the largest segments of the Human vertebral column, vertebral column and are characterized by the absence o ...

. The inferior vena cava is the lower (" inferior") of the two

venae cavae The venae cavae (; from the Latin Latin (, or , ) is a classical language A classical language is a language A language is a structured system of communication Communication (from Latin ''communicare'', meaning "to share" or ...

, the two large

vein Veins are blood vessels The blood vessels are the components of the circulatory system The circulatory system, also called the cardiovascular system or the vascular system, is an organ system An organ system is a biological system A b ...

vein

s that carry deoxygenated

from the body to the right atrium of the heart: the inferior vena cava carries blood from the lower half of the body whilst the

superior vena cava The superior vena cava (SVC) is the anatomical terms of location#Superior and inferior, superior of the two venae cavae, the great vein, venous trunks that return deoxygenated blood from the circulatory system, systemic circulation to the atrium ...

carries blood from the upper half of the body. Together, the venae cavae (in addition to the

coronary sinus The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle (myocardium). It delivers less-oxygenated blood to the right atrium, as do the superior vena cava, superior and inferior v ...

, which carries blood from the muscle of the heart itself) form the venous counterparts of the

aorta The aorta ( ) is the main and largest artery An artery (plural arteries) () is a blood vessel The blood vessels are the components of the circulatory system The circulatory system, also called the cardiovascular system or the vas ...

aorta

. It is a large

retroperitoneal The retroperitoneal space (retroperitoneum) is the spatium, anatomical space (sometimes a potential space) behind (''retro'') the peritoneum. It has no specific delineating anatomical structures. Organs are retroperitoneal if they have peritoneum o ...

vein that lies posterior to the

abdominal cavity The abdominal cavity is a large body cavity A body cavity is any space or compartment, or potential space Potential generally refers to a currently unrealized ability. The term is used in a wide variety of fields, from physics to the social sci ...

and runs along the right side of the

vertebral column The vertebral column, also known as the backbone or spine, is part of the axial skeleton Axial may refer to: * one of the describing relationships in an animal body * and submarine volcano off Oregon, USA * , a ghost town * In geometry: :* ...

. It enters the right auricle at the lower right, back side of the heart. The name derives from la, vena, "vein", cavus, "hollow".

Structure

The IVC is formed by the joining of the left and right

s and brings collected blood into the

of the heart. It also

joins Join may refer to: * Join (law) In law, a joinder is the joining of two or more legal issues together. Procedurally, a joinder allows multiple issues to be heard in one hearing or trial and is done when the issues or parties involved overlap su ...

with the

azygos vein The azygos vein is a vein running up the right side of the thoracic vertebral column The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate ...

(which runs on the right side of the vertebral column) and venous

plexus A plexus (from the Latin for "braid") is a branching network of vessels or Nerve, nerves. The vessels may be Blood vessel, blood vessels (veins, capillaries) or Lymphatic vessel, lymphatic vessels. The nerves are typically Axon, axons outside the ...

es next to the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column. It encloses the central canal of the spinal cord, which contain ...

. The inferior vena cava begins as the left and right common iliac veins behind the

abdomen The abdomen (colloquially called the belly, tummy, midriff or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the Trunk (anatomy) ...

abdomen

unite, at about the level of L5. It passes through the

thoracic diaphragm The thoracic diaphragm, or simply the diaphragm ( grc, διάφραγμα, diáphragma, partition), is a sheet of internal skeletal muscle Skeletal muscles (commonly referred to as muscles) are Organ (biology), organs of the vertebrate muscu ...

at the caval opening at the level of

. It passes to the right of the

descending aorta The descending aorta is part of the aorta, the largest artery in the Human body, body. The descending aorta begins at the aortic arch and runs down through the chest and abdomen. The descending aorta anatomically consists of two portions or segments ...

Tributaries

The specific levels of the tributaries are as follows: Because the inferior vena cava is located to the right of the midline, drainage of the tributaries is not always symmetrical. On the right, the

gonadal vein In medicine, gonadal vein refers to the blood vessel that carries blood away from the gonad (Testicle, testis, ovary) toward the heart. These are different arteries in Woman, women and Man, men, with the same embryological origin. * Female: ovarian ...

s and

suprarenal vein The Suprarenal veins are two in number: * the ''right'' ends in the inferior vena cava. * the ''left'' ends in the renal vein, left renal or left inferior phrenic vein. They receive blood from the adrenal glands and will sometimes form anastomoses w ...

s drain into the inferior vena cava directly. On the left, they drain into the

renal vein The renal veins are vein Veins are blood vessels The blood vessels are the components of the circulatory system The circulatory system, also called the cardiovascular system or the vascular system, is an organ system An organ system ...

which in turn drains into the inferior vena cava. By contrast, all the lumbar veins and

hepatic veins The hepatic veins are the vein Veins are blood vessels The blood vessels are the components of the circulatory system The circulatory system, also called the cardiovascular system or the vascular system, is an organ system An organ ...

usually drain directly into the inferior vena cava.

Development

In the

embryo An embryo is the early stage of development of a multicellular organism A multicellular organism is an organism In biology, an organism () is any organic, life, living system that functions as an individual entity. All organisms ar ...

embryo

, the inferior vena cava and right auricle are separated by the valve of the inferior vena cava, also known as the ''Eustachian valve''. In the adult, this valve typically has totally regressed or remains as a small fold of

endocardium The endocardium is the innermost layer of tissue that lines the chambers of the heart The heart is a muscle, muscular Organ (anatomy), organ in most animals, which pumps blood through the blood vessels of the circulatory system. The pumped ...

Variation

Rarely, the inferior vena cava may vary in its size and position. In

transposition of the great arteries Transposition of the great vessels (TGV) is a group of congenital congenital heart defect, heart defects involving an abnormal spatial arrangement of any of the great vessels: superior vena cava, superior and/or inferior vena cava, inferior venae ...

the inferior vena cava may lie on the left. In between 0.2% to 0.3% of people, the inferior vena cava may be duplicated beneath the level of the renal veins.

Function

The inferior vena cava is a

. It carries deoxygenated blood from the lower half of the body to the

of the

. The corresponding vein that carries deoxygenated blood from the upper half of the body is the

Clinical significance

Health problems attributed to the IVC are most often associated with it being compressed (ruptures are rare because it has a low intraluminal

pressure Pressure (symbol: ''p'' or ''P'') is the force In physics, a force is an influence that can change the motion (physics), motion of an Physical object, object. A force can cause an object with mass to change its velocity (e.g. moving fr ...

). Typical sources of external pressure are an enlarged

(

abdominal aortic aneurysm Abdominal aortic aneurysm (AAA or triple A) is a localized enlargement of the abdominal aorta such that the diameter is greater than 3 cm or more than 50% larger than normal. They usually cause no symptoms, except during rupture. Occasionall ...

), the

gravid In biology and medicine, human medicine, gravidity and parity are the number of times a woman is or has been pregnant (gravidity) and carried the pregnancies to a viable gestational age (parity). These terms are usually coupled, sometimes with addi ...

gravid

uterus The uterus (from Latin "uterus", plural ''uteri'') or womb () is the main female hormone-responsive, sex organ, secondary sex organ of the reproductive system in humans and most other mammals. Things occurring in the uterus are described with t ...

uterus

( aortocaval compression syndrome) and abdominal malignancies, such as

colorectal cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer Cancer is a group of diseases A disease is a particular abnormal condition that negatively affects the structure o ...

renal cell carcinoma Renal cell carcinoma (RCC) is a kidney cancer#REDIRECT Kidney cancer Kidney cancer, also known as renal cancer, is a group of cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or Metastasis, ...

and

ovarian cancer Ovarian cancer is a cancer that forms in or on an ovary. It results in abnormal cells (biology), cells that have the ability to invade or metastasis, spread to other parts of the body. When this process begins, there may be no or only vague sympto ...

. Since the inferior vena cava is primarily a right-sided structure, unconscious pregnant women should be turned on to their left side (the

recovery position In first aid First aid is the first and immediate assistance given to any person suffering from either a minor or serious illness A disease is a particular abnormal condition that negatively affects the structure or function of al ...

), to relieve pressure on it and facilitate venous return. In rare cases, straining associated with

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can lead to restricted blood flow through the IVC and result in

syncope Syncope may refer to: * Syncope (medicine), also known as fainting * Syncope (phonology), the loss of one or more sounds, particularly an unstressed vowel, from the interior of a word * Syncopation, a musical effect caused by off-beat or otherwise ...

(fainting). Blockage of the inferior vena cava is rare and is treated urgently as a life-threatening condition. It is associated with

deep vein thrombosis Deep vein thrombosis (DVT) is a type of venous thrombosis Venous thrombosis is blockage of a vein caused by a thrombus (blood clot). A common form of venous thrombosis is deep vein thrombosis (DVT), when a blood clot forms in the deep veins. ...

, IVC filters,

liver transplantation Liver transplantation or hepatic transplantation is the replacement of a diseased liver with the healthy liver The liver is an organ Organ may refer to: Biology * Organ (anatomy) An organ is a group of Tissue (biology), tissues with si ...

and

surgical procedures Many surgical procedure Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical or dental specialty that uses operative manual and instrumental techniques on a per ...

such as the insertion of a

catheter In medicine Medicine is the science Science () is a systematic enterprise that builds and organizes knowledge Knowledge is a familiarity, awareness, or understanding of someone or something, such as facts ( descriptive knowledge) ...

in the

femoral vein In the human body The human body is the structure of a Human, human being. It is composed of many different types of Cell (biology), cells that together create Tissue (biology), tissues and subsequently organ systems. They ensure homeostasi ...

in the

groin In human anatomy The human body is the structure of a human being Humans (''Homo sapiens'') are the most abundant and widespread species In biology, a species is the basic unit of biological classification, classification and a ...

.Geehan DM, Inferior Vena Caval Thrombosis, emedicine.com, URL: http://www.emedicine.com/med/topic2718.htm, Accessed: August 3, 2005. Major Veins

Trauma to the vena cava is usually fatal as unstoppable excessive blood loss occurs.

Additional images

File:Inferiorvenacava.png, Inferior vena cava File:Slide10bek.JPG, Inferior vena cava front view File:Inferior vena cava filter.jpg, Image of an

inferior vena cava filter An inferior vena cava filter is a type of vascular filter, a medical Medicine is the art, science Science (from the Latin word ''scientia'', meaning "knowledge") is a systematic enterprise that Scientific method, builds and Taxonomy (gene ...

File:3D Medical Animation Inferior Vena Filter.jpg, Image showing an inferior vena cava filter in its position

References

External links

* - "Posterior Abdominal Wall: Tributaries to the Inferior Vena Cava" * {{Authority control Veins of the torso