Prevention of pulmonary embolism by caval interruption with a Greenfield vena cava filter: a report of four cases.

Interruption of the vena cava is the treatment of choice for patients with thrombosis of the femoral or iliac vein in whom anticoagulants have to be discontinued or cannot prevent recurrent pulmonary embolism. The technique of interruption of the vena cava is outlined and illustrated by the case history of four patients, treated with a Greenfield vena cava filter.