Taking the inferior out of inferior vena cava filter follow-up

To the Editor: Follow-up of inferior vena cava (IVC) filters after insertion is a task that is variably successful. This was highlighted by a recent article describing poor removal rates of IVC filters at our institution between 2007 and 2009.1 Since that time, the interventional radiology (IR) department has established a filter database and clinic with the aim of improving IVC filter monitoring and removal. This radiology-driven initiative has been integrated into the standard interventional procedures and has proven extremely effective. Based on the success of this program, we advocate strongly that IVC filter follow-up should be the responsibility of those who provide the insertion service.

Between 2011 and 2013, all 87 IVC filters inserted by IR at St Vincent’s Hospital Melbourne have been accounted for; 44 have been removed, 33 were planned not for removal (eg, patients with a poor prognosis or contraindications), and 10 are awaiting removal or review in our IR clinic. The average indwelling time for IVC filters inserted between 2011 and 2013 was 23 weeks (range, 1–130 weeks), with 71/87 filters remaining in situ for less than 6 months. The average time in situ fell from 35 weeks in 2011 to 14 weeks in 2013. These results contrast with 2008–2010 data from our institution, where only 16/68 IVC filters were removed or planned for removal, 19/68 were planned not for removal or the patient was deceased, and 33/68 were lost to follow-up (Box).

Concerns about inadequate IVC filter removal and follow-up have been reported in the literature, particularly as the use of filters has increased.2,3 Potential complications associated with “forgotten” IVC filters include thrombogenesis, caval perforation, and filter fracture and migration. However, the important role of IR in tracking and removing lost filters is becoming widely recognised, with a number of studies outlining improvements in IVC filter follow-up that have resulted from radiology-led initiatives.4,5 Our data support the conclusion that IR departments, through easily implemented strategies, can and should take responsibility for tracking and removing all IVC filters they insert.

Inferior vena cava filter outcomes at St Vincent’s Hospital Melbourne