Inferior Vena Cava Filter Use at a Large Community Hospital: A Cross-Sectional Analysis

Introduction: Inferior vena cava (IVC) filters are considered among patients who have sustained a recent lower extremity deep vein thrombosis (DVT) and/or pulmonary embolism (PE) with a contraindication to anticoagulation. IVC filter use has risen in recent decades despite a lack of data on the effectiveness of IVC filters in reducing venous thromboembolism (VTE)-related mortality. Moreover, IVC filters may be associated with significant morbidity, including filter migration, IVC thrombosis, and fatal bleeding. Prolonged insertion of an IVC filter risks endothelialization which renders later attempts at removal ineffective, and raises the risk of complications.

In this study, we aimed to characterize the pattern of IVC filter use at a large community-based hospital. Specifically, we characterized the indications for IVC filter insertion, rates of IVC filter removal, and filter-associated complications.

Methods: A retrospective cohort study of adult patients (>18 years) who received an IVC filter between January 1, 2005 - February 28, 2022 at Windsor Regional Hospital (WRH), which is a large community-based hospital with academic affiliations in Southwestern Ontario, Canada. Data were collected using RedCAP software and analyzed using descriptive methods.

Results: To date, we have reviewed 89 patient charts from 2019-2022. Patients with IVC filters inserted through WRH were most often male (58.4%) with a median age of 68 years. The most common indications for IVC filters included recent VTE (DVT and/or PE within 3 months) and active bleeding (43.8%), and recent VTE with a need for anticoagulation interruption for surgery (32.6%). Approximately 21% (19 patients) of IVC filters were inserted for indications outside recommended guidelines, including: need for interruption of anticoagulation in patients with a remote history of VTE (31.6%) or prior to surgery (15.8%), recent VTE & active bleed but anticoagulant therapy not discontinued (21.1%), surgical prophylaxis (10.5%), recent VTE & risk of bleeding with no active bleed (10.5%), failure of anticoagulation (5.3%), and massive PE with residual DVT (5.3%). Only 34.8% of patients had successful removal of their IVC filter with an average of 1.2 attempts at filter removal per patient. At least 4 patients (4.5%) have experienced complications relating to their IVC filter, including IVC thrombotic occlusion (50%) and IVC filter migration (50%).

Conclusions: Approximately 21% of IVC filters were inserted for indications that fall outside of current guidelines at a large community-based hospital in Ontario, Canada. Moreover, 65% of IVC filters were not removed which is consistent with rates reported in other studies, and significantly raises the risk of IVC filter complications. Given that the majority of patient care occurs in the community setting, further efforts are needed to understand patterns of IVC filter use at other community hospitals. As well, our findings further support the need for development of concrete guidelines on indications for IVC filter use and monitoring practices.

No relevant conflicts of interest to declare.