Extended interval for retrieval of vena cava filters is safe and may maximize protection against pulmonary embolism.

Background: Retrieval of optional vena cava filters (VCF) has been demonstrated to be safe and feasible in injured patients in 4 recent studies. However, 2 pulmonary emboli PE were reported in these studies with mean implant durations less than 19 days. In light of these occurrences, we changed our practice for VCF retrieval when patients had recovered from their injuries and at least 30 days after their discharge, or had been stable on therapeutic anticoagulation for deep venous thrombosis (DVT) or PE for at least 2 weeks. The aim of the current study was to assess the safety of this approach.
Methods: A review of prospectively collected data on optional VCF over a 16-month period. The filters were inserted prophylactically per an institutional practice guideline or for the presence of DVT or PE with a contraindication and/or complication to anticoagulation. All patients underwent duplex imaging of the lower extremities and had pre- and post- retrieval cavagrams. Demographics, duration of implantation, and complications were recorded.
Results: Eighty-three patients had optional VCF inserted since the change in our clinical practice. Indications included prophylaxis for high-risk trauma patients (n = 58), DVT or PE with acute contraindication to therapeutic anticoagulation (n = 22), or complications of anticoagulation (n = 3). Two patients developed lower extremity DVT after filter insertion and 1 patient developed a vena cava thrombosis. Retrieval was successful in 47 of 54 cases (87%) attempted. Median implantation duration was 142 days (range 17-475). A filter strut fracture occurred during retrieval without further consequences. No post-insertion or post-retrieval PE occurred in this study.
Conclusion: Extended intervals for retrieval of VCF are safe and may maximize protection against pulmonary embolism.