Retrieving “Nonretrievable” Inferior Vena Caval Greenfield Filters: A Therapeutic Option for Filter Malpositioning

Abstract

Filter malpositioning is a possible complication of inferior vena caval (IVC) filter insertion that may result in inadequate protection from pulmonary embolism. For nonretrievable filters, this is traditionally managed with either observation or additional filter placement. The purpose of this study is determine the incidence of filter malpositioning after bedside insertion under duplex ultrasound (DUS) or intravascular ultrasound (IVUS) guidance, and to report techniques for retrieving and repositioning IVC filters previously considered nonretrievable. All IVC filter insertions performed under DUS or IVUS guidance over an 8-year period were identified. Data regarding insertion technique, device used, and technical success were retrospectively collected. Cases of IVC filter malpositioning were determined and form the basis of this study. Technical details for IVC filter retrieval and repositioning are described. Of 486 patients undergoing DUS (n = 435) or IVUS (n = 51) guided IVC filter insertion, 12 patients (2.4%) had inadequate positioning as determined by postoperative radiography. Two of these patients had no further filter manipulation, three had a second filter placed under fluoroscopic guidance, and the most recent five had filters retrieved and repositioned under fluoroscopic guidance. Of those patients undergoing retrieval and repositioning, all five had Greenfield filters, which are not traditionally regarded as retrievable. All attempted retrievals or replacements were technically successful without additional filter-related complications. Bedside IVC filter insertion under DUS or IVUS guidance has a low incidence of filter misplacement. Although not traditionally regarded as retrievable, Greenfield filters can be safely retrieved and repositioned using advanced endovascular techniques in the event of malpositioning.