The better main vein (SVC) is the better of the two cava veins, the great venous trunks that return oxygen-free blood from the systemic circulation to the right atrium of the heart. It is a large diameter (24 mm) vein, but short, which receives a venous return from the upper half of the body, above the diaphragm. (Venous return from the lower half, below the diaphragm, flows through the lower main vein). The SVC is located in the front right upper portion of the mediastinum. This is a typical central venous access (CVA) via a central venous catheter or central catheter placed peripherally. References to “cava” without further specification usually refer to SVC.
superior vena cava functions & structure
Superior vena cava formes with left and right brachiocephalic veins (also called veins). It also takes blood from the upper limbs, eyes, and neck, behind the lower limit of the first right bone cartilage. It flows vertically downstream of the first intercostal space and receives the azygos vein just before the puncture of fibrous pericardium opposite to the right cartilage of the hip, and its lower part is intramuscular. And then it ends in the upper and the rear part of the sine venarum right atrium, in the upper right front of the heart. It is also known as a cranial vein in other animals.
In superior vena cava functions, the lack of a valve divides the main vein from the right atrium. As a result, (right) vestibular spasms and (right) ventricles are carried to the internal jugular vein, and through the muscle can be perceived as cervical venous pressure. A better obstruction of the vena cava means a partial or complete obstruction of the superior vena cava, usually in the context of cancer, such as lung cancer, metastatic carcinoma or lymphoma.
Clogging can lead to enlarged veins in the head and neck, and can also cause shortness of breath, cough, chest pain and difficulty in swallowing. Pemberton’s sign may be positive. The obstruction-inducing tumors can be treated with chemotherapy and/or radiotherapy to reduce their effects, and corticosteroids may also be administered.