This large vein receives blood from the upper extremities of the body.
The superior vena cava is a large vein that transports deoxygenated blood from the parts of the body that lie superior to the diaphragm (e.g., the head, neck, upper arms) to the right atrium. The superior vena cava is formed by the brachiocephalic or innominate veins, which receive blood from the upper limbs. It then passes downward and posterior to the second and third intercostal spaces where it receives the azygos vein before it enters the pericardium .
White, Hunter J., and Michael P. Soos. Anatomy, Thorax, Superior Vena Cava. NCBI StatPearls [Internet], 2019, https://www.ncbi.nlm.nih.gov/books/NBK545255/.
Superior vena cava