Absence of the inferior vena cava is a rare vascular anomaly, which usually remains asymptomatic in childhood. It is recognized as the risk factor for deep venous thrombosis, since the collateral circulation does not provide adequate drainage of the lower limbs.
The human heart and nearby structures, with superior and inferior vena cava labeled at left side of image. The venae cavae (/ˈviËni ˈkeɪvi/; from the Latin for "hollow veins", singular "vena cava" /ˈviËnÉ™ ˈkeɪvÉ™/) are two large veins (great vessels) that return deoxygenated blood from the body into the heart.
A blockage in the inferior vena cava (IVC) can lead to chronic leg swelling, pain, and immobility, according to the University of California Los Angeles (UCLA) IVC Filter Clinic. There may be other health complications depending on a person's age and preexisting medical conditions.
The vena cava are the two largest veins that carry blood into the right upper chamber of the heart (the right atrium). The superior vena cava carries blood from the brain and arms into the top of the right atrium.
What makes the IVC different from other veins is that there are no valves within the vein to keep blood moving forward instead of backward, which is how the typical anatomy of a vein works. To prevent the blood from moving back into the body, valves made up of tissue in the vein close as the blood through it.
Who is at risk for SVCS? SVCS is most often seen in people with cancer. It's most common with lung cancer or non-Hodgkin lymphoma. Far less often, it's linked to other causes, such as infection or a blood clot in the SVC caused by an implanted medical device.
Superior vena cava syndrome (SVCS) is a collection of symptoms that usually occur in patients who have lung cancer, non-Hodgkin lymphoma, or other cancers. It also can occur from noncancer causes. Although serious when it occurs in adults, this syndrome is life-threatening in children.
The superior vena cava derives from the proximal portion of the right anterior cardinal vein and the right common cardinal vein at a point that is caudal to the transverse anastomosis in the embryo.
Although SVC syndrome is a clinical diagnosis, plain radiography, computed tomography (CT) and venography are used for confirmation (1). Recommended treatments for cancer-related SVC syndrome include chemotherapy and radiation to reduce the tumour that is causing the obstruction.
Location. The superior vena cava is formed by the left and right brachiocephalic veins—also referred to as the innominate veins—on the right side of the upper chest, posterior (behind) to the lower border of the first costal cartilage.
The vena cava has two parts: the superior vena cava and the inferior vena cava. The superior vena cava carries blood from the head, neck, arms, and chest. The inferior vena cava carries blood from the legs, feet, and organs in the abdomen and pelvis. The vena cava is the largest vein in the body.
The superior vena cava carries oxygen-poor blood from the upper parts of your body, including your head, chest, arms, and neck. Carries deoxygenated blood from lower regions of the body to right atrium.
Jugular vein, any of several veins of the neck that drain blood from the brain, face, and neck, returning it to the heart via the superior vena cava. The internal jugular veins unite with the subclavian veins to form the brachiocephalic veins and drain blood from the brain, the face, and the neck.
The inferior vena cava is the largest vein in the human body. It collects blood from veins serving the tissues inferior to the heart and returns this blood to the right atrium of the heart. Although the vena cava is very large in diameter, its walls are incredibly thin due to the low pressure exerted by venous blood.
Structure of blood vessels
| Artery | Capillary |
|---|
| Direction | Away from the heart | From arteries to veins |
| Pressure | High | Low |
| Size of hole (lumen) | Small | Very small |
| Wall thickness | Thick | One cell thick |
The adventitia–media boundary is also more obvious in aorta than it is in vena cava. Additionally, the average aorta thickness (1.32 ± 0.09 mm) was significantly (p < 0.05) thicker than vena cava (0.66 ± 0.07 mm).
Many veins contain one-way valves to ensure the forward flow of blood back toward the heart. The IVC, however, does not contain such valves, and forward flow to the heart is driven by the differential pressure created by normal respiration.
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
Blood comes into the right atrium from the body, moves into the right ventricle and is pushed into the pulmonary arteries in the lungs. After picking up oxygen, the blood travels back to the heart through the pulmonary veins into the left atrium, to the left ventricle and out to the body's tissues through the aorta.
Blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs. Blood leaves the heart through the aortic valve, into the aorta and to the body. This pattern is repeated, causing blood to flow continuously to the heart, lungs and body.
The higher pressure generated by the left heart produces a gradient which moves blood from the left heart, through the body and into the right side of the heart. When the left ventricle (LV) contracts, it generates a systolic blood pressure of 100-140 millimeters of Hg (mm Hg).
The right side of your heart receives oxygen-poor blood from your veins and pumps it to your lungs, where the blood picks up oxygen and gets rid of carbon dioxide. The left side of your heart receives oxygen-rich blood from your lungs and pumps it through your arteries to the rest of your body.
Deoxygenated blood is received from the systemic circulation into the right atrium, it is pumped into the right ventricle and then through the pulmonary artery into the lungs.
The heart works as two pumps, one on the right and one on the left, working simultaneously. Blood flows from the right atrium to the right ventricle, and then is pumped to the lungs to receive oxygen. From the lungs, the blood flows to the left atrium, then to the left ventricle.
Deoxygenated blood refers to the blood that has a low oxygen saturation relative to blood leaving the lungs. The oxygenated blood is also called arterial blood. The deoxygenated blood is also called venous blood.
