The Superior Vena Cava - Podcast Version TeachMeAnatomy 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The superior vena cava (SVC) is a large, valveless vein that conveys venous blood from the upper half of the body and returns it to the right atrium. In this article, we will look at the anatomy of the superior vena cava – its position, tributaries, and clinical correlations. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Anatomical Position The superior vena cava is classified as a large vein, with a wide diameter of up to 2cm and a length of approximately 7cm. It arises from the union of the left and right brachiocephalic veins, posterior to the first right costal cartilage. It descends vertically through the superior mediastinum, behind the intercostal spaces and to the right of the aorta and trachea. At the level of the second costal cartilage, the SVC enters the middle mediastinum and becomes surrounded by the fibrous pericardium. It terminates by emptying into the superior aspect of the right atrium at the level of the third costal cartilage. By TeachMeSeries Ltd (2026) Fig 1Anterior view of the superior vena cava. Clinical Relevance Jugular Venous Pressure The superior vena cava is a valveless structure. This allows the pressure in the right atrium to be conducted upwards into the right internal jugular vein. Visualisation of the right internal jugular vein is an indicator of the jugular venous pressure – which in turn represents the pressure in the right atrium. To examine, the patient should be at a 45° angle with their head turned slightly to the left. The JVP can be identified as a pulsation between the two heads of the sternocleidomastoid muscle. Causes of a raised JVP include right-sided heart failure, pulmonary hypertension, and SVC obstruction. Pro Feature - Dissection Atlas Contents of the superior mediastinum. Contents of the superior mediastinum. You've Discovered a Pro Feature Access our Dissection Image Library Enhance your understanding with high-resolution dissection images showcasing real-life anatomy. Learn More Tributaries The superior vena cava contains venous blood from the head, neck, both upper limbs and from structures within the thorax It is formed by the union of the right and left brachiocephalic veins – which provide venous drainage of the head, neck, and upper limbs. At the level of T4, the superior vena cava receives the azygos vein, which drains the upper lumbar region and thoracic wall. The SVC receives tributaries from several minor vein groups: Mediastinal veins Oesophageal veins Pericardial veins Clinical Relevance Superior Vena Cava Obstruction The superior vena cava is a thin-walled, low pressure vessel which makes it vulnerable to compression. Superior vena cava obstruction can occur either due to external compression or from an occlusion within the vessel lumen itself. The most common cause of SVC obstruction is malignancy, typically from lung cancer, lymphoma, or metastatic disease. Vessel obstruction interrupts venous return and can lead to swelling in the neck, face, and upper limbs. Clinical features include shortness of breath and distension of the veins of the face and upper limb. SVC obstruction can be assessed clinically by performing Pemberton’s test. The patient is asked to raise both arms above their head – a positive test is indicated if facial oedema or cyanosis occurs after approximately 1 minute. Do you think you’re ready? Take the quiz below Pro Feature - Quiz The Superior Vena Cava Question 1 of 3 Submitting... Skip Next Rate question: You scored 0% Skipped: 0/3 1800 More Questions Available Upgrade to TeachMeAnatomy Pro Challenge yourself with over 1800 multiple-choice questions to reinforce learning Learn More Frequent questions What is the superior vena cava and its primary function? The superior vena cava (SVC) is a large, valveless vein that transports deoxygenated blood from the upper half of the body to the right atrium of the heart. It plays a crucial role in venous return, collecting blood from the head, neck, upper limbs, and thoracic structures. Where is the superior vena cava located anatomically? The superior vena cava is positioned in the superior mediastinum, arising from the junction of the left and right brachiocephalic veins. It descends vertically, passing behind the intercostal spaces and to the right of the aorta and trachea before emptying into the right atrium. How can jugular venous pressure (JVP) be assessed using the superior vena cava? Jugular venous pressure can be evaluated by observing the right internal jugular vein, which reflects the pressure in the right atrium due to the SVC's valveless nature. The patient should be at a 45° angle, and the pulsations can be seen between the sternocleidomastoid muscle heads. What are the common causes of superior vena cava obstruction? Superior vena cava obstruction is often caused by external compression or occlusion within the vessel, with malignancies such as lung cancer and lymphoma being the most frequent culprits. This condition can disrupt venous return, leading to symptoms like swelling in the face, neck, and upper limbs. What clinical test can indicate superior vena cava obstruction? Pemberton’s test is used to assess for superior vena cava obstruction by having the patient raise both arms above their head. A positive result, indicated by facial swelling or cyanosis after about one minute, suggests venous return issues due to SVC obstruction. Rate This Article