RESUMO
PURPOSE: To identify risk factors for strut perforation following Celect inferior vena cava (IVC) filter (IVCF) placement and to use finite element modeling to predict the mechanical impact of long-dwelling filters. MATERIALS AND METHODS: Ninety-one patients with three computed tomography (CT) studies were evaluated following Celect IVCF placement (2007-2013). Three-dimensional finite element models of the Celect IVCF were developed to simulate mechanical deformation of the IVCF encountered in vivo. Simulated forces applied by the primary struts on the IVC wall were measured as a function of luminal area and tilt angle. RESULTS: Although 33 patients (36%) showed primary strut perforation on initial follow-up CT, 60 patients (66%) showed progressive perforation over time (P < .0001), with 72 patients (79%) showing primary strut perforation on the final CT (average, 554 d). Female patients (P = .004) and those with malignancy history (P = .01) had significantly higher perforation rates at a given time. Caval area also decreased after primary filter strut perforation, and we therefore proposed that this was the mechanism for progressive perforation. Consistent with this mechanism, three-dimensional finite element modeling demonstrated increasing strut force with decreasing IVC diameter. CONCLUSIONS: Celect IVCF primary strut perforation is progressive over time and is more common in female patients and those with a history of malignancy. In addition, this progressive perforation may be predicted by three-dimensional finite element modeling. These patient populations may require closer follow-up after IVCF placement to prevent or reduce the risk for filter complication or worsening perforation.
