Objective: Retrievable inferior vena cava filters (IVCF) have been developed because permanent filters have been associated with an increased risk of recurrent deep venous thrombosis. There is no data on the interactions of IVCF with the inferior vena cava (intrafilter thrombi, insertion through the venous wall) even though this may alter the course after retrieval of the IVCF.
Methods: A review of 85 consecutive patients undergoing retrieval of IVCF placed at a single center was performed from January 1, 2010 and December 31, 2014. Inferior vena cava filter were examined for presence of intrafilter thrombus at time of retrieval. Filter position and presence of intraluminal thrombus were examined. Patient outcomes, including recurrence of deep vein thrombosis (DVT) and death, were captured at 3 month followup.
Results: Eighty five patients were identified, with intrafilter thrombi found in 69 (81%) patients and venous wall fragments found in 75 (88%) patients. However, their presence was not associated with an increased risk of recurrent venous thromboembolism (VTE) or death during follow up.
Conclusions: Intrafilter thrombi and venous wall fragments are frequently found in removed IVCF but are not associated with a worse prognosis. They may not modify the therapeutic management of patients.
Keywords: deep venous thrombosis; inferior vena cava filters; mechanism; pathological evolution; pulmonary embolism; retrievable.