LIGATION of the inferior vena cava (IVC) has long been the procedure of choice for the treatment of large recurrent pulmonary emboli. Caval ligation has also been advocated for patients with cor pulmonale due to repeated showers of small emboli, for patients with septic emboli from pelvic suppurative disease, and prophylactically in certain selected patients. Studies have shown that approximately 75% to 90% of all pulmonary emboli can be expected to originate below the usual site of inferior vena caval ligation and thus are amenable to treatment by this procedure.1-5
At first thought, venous ligation above the source of the emboli seems to be a reasonable approach. However, blood from the legs and pelvis must return to the heart by some route and, following ligation, this is accomplished through collateral venous channels. Conceivably, vessels large enough to accomodate this amount of blood flow are also capable of carrying emboli