Inferior vena cava (IVC) filters are placed in a large vein in the abdomen where blood returns to the heart from the lower body and legs. The filters trap large clot fragments moving toward the heart or lungs, reports RadiologyInfo.org.
IVC filters are typically inserted through the groin femoral vein or internal jugular vein of the neck and work to capture material from clots originating in veins of the legs or pelvis. The filter allows blood to continue to flow around the trapped clot, according to the University of Michigan Department of Surgery. Without the device, clot matter may cause pulmonary embolism -where the artery carrying blood from the heart to the lungs is blocked- potentially resulting in death.