Outcomes in venous thromboembolism with retained vs removed inferior vena cava filters: an analysis from the Registro Informatizado de Enfermedad TromboEmbólica

Background: Retrievable inferior vena cava (IVC) filters are used in patients with acute venous thromboembolism (VTE) who have temporary contraindications to anticoagulation. Although guidelines recommend removing filters once anticoagulation is feasible, many filters remain in place. Long-term consequences of retention remain unclear. Objectives: This study compared clinical outcomes in patients with VTE and retrievable IVC filters, according to filter status and anticoagulation use. Methods: We analyzed patients from the international RIETE (Registro Informatizado de Enfermedad TromboEmbólica) registry who received retrievable IVC filters. Outcomes from day 90 onward were stratified by filter status (removed vs retained) and anticoagulation (on vs off). Primary endpoints included VTE recurrence, major bleeding, and all-cause mortality. Filter-related complications were assessed. Results: Among 1186 patients (mean age, 62 years; 51% male), 51.9% had filters removed by day 90. Patients with retained filters more often had active cancer and received longer anticoagulation, primarily low-molecular-weight heparin. VTE recurrence was higher with retained filters (4.5-6.5 vs 1.2-1.3 events per 100 patient-years), mainly as deep vein thrombosis; removal was associated with lower risk (adjusted incidence rate ratio, 0.29; 95% CI, 0.15-0.54). All-cause mortality was higher in patients with retained filters (7.3-17.7 vs 3.8-4.5; removal: adjusted odds ratio, 0.53; 95% CI, 0.34-0.81). Major bleeding was infrequent, with higher rates in patients with retained filters off anticoagulation. Filter-related complications were rare and did not differ significantly between groups after adjustment. Conclusion: In this large registry, retained IVC filters were associated with higher risk of VTE recurrence, even with extended anticoagulation. Findings support structured follow-up and timely filter retrieval.