 An inferior vena cava filter is sometimes also called a green-filled filter and this is a filter that's inserted in the inferior vena cava in the patient's abdomen for patients who are at high risk or who have an identified blood clot in the lower extremities. And the risk here is that if that blood clot were to break off from the lower extremities, it would travel through the inferior vena cava and then could settle either in the right atrium or go all the way to the lungs causing a pulmonary embolism. So if the patient is at high risk and there are no other treatment options available or the patient might not be able to tolerate anticoagulants for whatever reason, this green-filled filter might be inserted. So check out my full video on venous thrombosis as well as atrial fibrillation about this filter on YouTube.