Technical modifications in the placement of inferior vena caval filter devices.

Placement of 151 Mobin-Uddin vena caval umbrella filters and 17 Kimray-Greenfield vena caval filters since 1972 led us to make a number of technical modifications. The operative procedure is performed with local anesthesia in the vascular radiology suite. If the right internal jugular vein is narrowed and cannot be dilated, an approach through the left internal jugular vein is possible. The filters are advanced under fluoroscopic control after direct visualization of both renal veins. Since the patient is awake, he can be asked to roll on the left side if there is a tendency for the filter to advance into the hepatic veins or the right renal vein. Release of the filter is most accurately accomplished by withdrawing the carrier rather than advancing the filter. The carrier is then removed under fluoroscopic control and the internal jugular vein ligated. These modifications have resulted in a success rate of nearly 100 percent in recent filter placements, an operative morbidity of 8.3 percent and a 30 day hospital mortality of 8.9 percent.