Non-retrieved inferior vena cava filters: causes and long-term follow-up

BACKGROUND: Temporary inferior vena cava (IVC) filters are not always retrieved. Information about longterm outcomes of patients with indwelling filters is scarce. Aims of our study were to assess reasons that preclude retrieval of temporary IVC filters and long-term outcomes and causes of death in patients with indwelling filters. MATERIALS AND METHODS: Retrospective observational study including all consecutive patients undergoing IVC filter insertion from January 2009 through December 2018. Patients with permanent filters and those with temporary filters not retrieved were followed from insertion until June 2020. RESULTS: We included 271 patients with a mean age of 63.8 years. The main indication for filter insertion was acute venous thromboembolism and contraindication for anticoagulation (83%). The filter was deemed as permanent in 24.4% of patients and temporary in 75.6%. Sixty six percent of temporary filters were retrieved; the main cause of non-retrieval was lack of planning / follow-up (57.9%). One hundred twelve patients (41.3%) remained with indwelling filters. After follow-up, 54.5% were alive and 45.5% had died, with a median survival time of 6.19 (95% CI, 2.63-9.75) years. The most frequent cause of death during follow-up was cancer (49%). The frequency of anticoagulant therapy was similar in both groups (57.4%% versus 54.9%). CONCLUSIONS: The main preventable cause of non-retrieval of temporary IVC filters was lack of planning / follow-up. Structured follow-up programs should be implemented to increase retrieval rates. In patients with indwelling filters, the main cause of death was cancer and extended anticoagulation was not associated with survival.