Inferior Vena Cava

Venous blood is derived back to the right side of the heart from the lower part of the body through the inferior vena cava (IVC). The IVC opens into the lowest part of the right atrium (RA) directed upward and backward by a rudimentary valve (Eustachian valve) at the level of the lower third of the ninth thoracic vertebra. The IVC is usually visualized and assessed by echocardiography using the subcostal approach. Respiratory changes and collapsibility of the IVC can be effectively used for the assessment of the right sided pressures and intravascular volume status [1–3]. IVC measurements can be done on the 2D- or M-mode recording of the IVC during at least one whole respiratory cycle. The recording should start from end expiration and involves inspiratory effort “sniff” followed by return to expiration again [1, 3]. IVC measurements should be done 2 cm away from the RA inlet [4]. IVC visualization can also help in assessment of several anatomical obstruction conditions such as IVC stenosis, thrombosis, and masses, in addition to several congenital abnormalities.