IVc

The inferior vena cava (IVC) is the large vein that returns blood from the lower body to the heart. It forms behind the right common iliac vein at the level of L5 and ascends along the right side of the vertebral column. It passes through the central tendon of the diaphragm at the caval opening (T8) to join the right atrium. The IVC can be divided into infrarenal, renal, and suprarenal segments (the latter includes hepatic). It receives blood from many tributaries, including the lumbar veins, gonadal veins, renal veins, hepatic veins, and, near the diaphragm, the phrenic and suprarenal veins.

Function and clinical significance: The IVC collects deoxygenated blood from the lower body and delivers it to the heart, playing a central role in venous return. Obstruction or narrowing can result from tumors, thrombosis, or external compression and may cause leg swelling, abdominal pain, or collateral venous circulation. IVC filters are devices placed partially within the IVC to prevent pulmonary embolism in patients who cannot receive anticoagulation; many filters are retrievable.

Anomalies: Congenital variations such as duplicated IVC or agenesis occur but are relatively rare; they may affect venous drainage and surgical planning.

Diagnosis and treatment: Imaging such as Doppler ultrasound, CT venography, or MR venography is used to evaluate IVC size and patency. Management depends on cause and may include anticoagulation, thrombolysis, or surgical/interventional procedures.

Other uses: In medical contexts, IVC is most commonly the inferior vena cava; other, less common meanings exist in different fields.