Optimal Time of Extraction Retrievable Inferior Vena Cava Filters in Venous Thromboembolic Treatment: Evidence Based Case Report

Abstract

Background: Inferior vena cava (IVC) filters have been proven to be significantly advantageous and clinically efficacious in the prevention of deathly venous thromboembolism, but also carry long-term risks, such as device failure, filter fracture, migration, penetration into adjacent structures, etc. Retrievable filters offer the same degree of protection, and subsequently lower those risk by removing them after they aren’t needed. Unfortunately, increasing use of retrievable filters leads to one alarming trend: there’s massive number of filters that are left for an extended time. Whether the time between deployment and retrieval affects filter’s technical success of retrieval remains questionable. Here is a case of a 45-year old woman who had undergone retrievable IVC filter due to pulmonary embolism risk. The patient only came to clinician for routine follow- up once, one month after deployment. One year later, the patient felt abdominal pain and asked to remove the filter. After one failed attempt, the clinician decided to leave the filter in situ as permanent filter. Method: Literature searching was conducted in several databases (ScienceDirect, EbscoHost, and ClinicalKey) using specified keywords. Six articles that had been passed exclusion and inclusion criteria, were eventually appraised and extracted. Results: Of all six articles that are included in this study, there are no standard time of retrieval. Each study provides data regarding their attempted retrieval, successful retrieval, and dwell time. Only two articles (Uberoi et al and Glocker et al) analyze the relationship between time of retrieval and successful retrieval. Uberoi et al claims filter retrieval statistically more successful if the dwell time is less than 9 weeks, whereas Glocker et al states the procedure is considerably more successful within 3-4 months (117 days) after deployment. The reasons of retrieval failure in these studies are varied, including device angulation, filter incorporation with IVC wall, and penetration to IVC wall and adjacent structures, or significant thrombus inside the filter. Conclusion: There are no standard time of retrieval, but clinicians could follow FDA recommendation by removing the filter when it isn’t necessarily needed. However, a time span of 3-4 months between implantation and retrieval can be respectable choice to make sure the maximum chance at retrieval success.