Role of Anticoagulation in Patients with Inferior Vena Cava Filter but with No Risk Factor or History of DVT/PE

Inferior Vena Cava (IVC) filters have been available for almost 40 years but their clinical utility and safety have not been completely evaluated in patients with no previous history of deep vein thrombosis (DVT) or pulmonary embolism (PE). The role of anticoagulation in patients with IVC filter with no history of DVT/PE is questionable. In this study, we try to determine if there is a role or benefit from anticoagulation in patients with an IVC filter placed but without any other risk factor for deep vein thrombosis (DVT) or pulmonary embolism (PE).

we retrospectively reviewed the charts of 562 patients who had an IVC filter placed between 2003 and 2005. 442 patients were excluded because they had a history of DVT/PE, or because of a hypercoagulable state (genetic predisposition, prolonged hospitalization/immobilization, surgery, or malignancy). Of the 120 remaining patients included in this study, 6 had their IVC filter removed. And therefore we only analyzed the charts of 114 patients who had a permanent IVC filter placed for prophylactic reasons. Group 1 consisted of 17 patients who received different forms of anticoagulation (subcutaneous heparin, low molecular weight heparin or coumadin). Group 2 consisted of the remaining 97 patients who did not receive any form of anticoagulation.

2 out of 17 patients in group 1 had a DVT and 14 out of 97 patients in group 2 had a DVT. The incidence of DVT was 11.8% in group 1 versus 14.4% in group 2 (p-value 0.770). The median onset of DVT/PE after IVC filter placement was 31 days. The median time of follow up was 77.33 months.

Patients who had a permanent prophylactic IVC filter placed but with no history or risk factors for DVT/PE appear to be at an elevated risk for new DVT/PEs. In these patients, the role of anticoagulation is questionable. With a median 6 year follow up, anticoagulation seemed to non significantly lower the risk of DVT/PE. Larger randomized prospective trials are needed to examine the efficacy and duration of anticoagulation in patients with a prophylactic IVC filter placed.

No relevant conflicts of interest to declare.