 the superior vena cava (also known as the cava or cva) is a large diameter, yet short, vein that carries deoxygenated blood from the upper half of the body to the heart's right atrium. it is located in the anterior right superior mediastinum.http://www.gpnotebook.co.uk/simplepage.cfm?id=463077437&linkid=32255&cook=no ==structure== it is formed by the left and right brachiocephalic veins (also referred to as the innominate veins), which also receive blood from the upper limbs, eyes and neck, behind the lower border of the first right costal cartilage. the azygos vein joins it just before it enters the right atrium, at the upper right front portion of the heart. it is also known as the cranial vena cava in animals. no valve divides the superior vena cava from the right atrium. as a result, the (right) atrial and (right) ventricular contractions are conducted up into the internal jugular vein and, through the sternocleidomastoid muscle, can be seen as the jugular venous pressure. ==clinical significance== superior vena cava obstruction refers to a partial or complete obstruction of the superior vena cava, typically in the context of cancer such as a cancer of the lung, metastatic cancer, or lymphoma. obstruction can lead to enlarged veins in the head and neck, and may also cause breathlessness, cough, chest pain, and difficulty swallowing. pemberton's sign may be positive. tumours causing obstruction may be treated with chemotherapy and/or radiotherapy to reduce their effects, and corticosteroids may also be given. in tricuspid valve regurgitation, these pulsations are very strong.  ==additional images==  image:gray480.png|diagram showing completion of development of the parietal veins. image:gray490.png|front view of heart and lungs. image:gray494.png|heart seen from above. file:slide1eeee.jpg|superior vena cava file:slide6eeee.jpg|superior vena cava file:slide13eeee.jpg|superior vena cava file:slide1xxxx.jpg|superior vena cava file:slide1wwww.jpg|superior vena cava file:slide12444.jpg| 
Veins_of_the_torso