Factors Influencing the Indwelling Time of Retrievable Inferior Vena Cava Filters in Fracture Patients With Deep Vein Thrombosis: A Retrospective Cohort Study.

Abstract

Aim: To investigate factors influencing the indwelling time of retrievable inferior vena cava filters (IVCFs) in fracture patients with deep vein thrombosis (DVT), particularly comparing Denali and Cordis filters and analyzing the impact of thrombus location and patient characteristics.

Methods: A retrospective cohort study was conducted from June 2017 to December 2021 at Shenyang Orthopedic Hospital, China. We analyzed 802 patients with fractures and acute DVT who underwent successful IVCF retrieval. Patients were stratified into Denali (n = 360) and Cordis (n = 442) groups, with DVT categorized into four subgroups: above-knee DVT (AKDVT), popliteal vein thrombosis (PVT), below-knee DVT (BKDVT), and mixed DVT (MDVT). The normality of continuous variables was assessed using the Kolmogorov-Smirnov test (p ≥ 0.05). Statistical analyses included Cox regression for hazard ratios (HRs), independent t-tests for normally distributed variables, chi-square tests for categorical variables (e.g., gender, diabetes prevalence), and Mann-Whitney U tests for non-normally distributed variables.

Results: A total of 802 patients underwent IVCF insertion and had their filters successfully removed. Significant differences in the indwelling time for AKDVT, PVT, BKDVT, and MDVT were observed between the Denali and Cordis groups (p < 0.001). In the Denali group, the indwelling times for AKDVT, PVT, BKDVT, and MDVT were 58, 67, 42, and 51 days, respectively, while in the Cordis group, the corresponding times were 21, 15.5, 16, and 19 days (p < 0.001). Cox regression analysis revealed that age influenced the indwelling time in the Denali group. In both the Denali and Cordis groups, metabolic factors such as diabetes, hypertension, and blood lipids were not significantly correlated with indwelling time (p > 0.05). Multivariate Cox regression identified that age ≥60 years (adjusted HR = 1.3, 95% confidence interval (CI) = 1.051-1.609, p = 0.016) and BKDVT (BKDVT vs. AKDVT: HR = 1.802, 95% CI = 1.029-3.157, p = 0.039) were predictors of prolonged indwelling time in the Denali group, while PVT (p = 0.943) and MDVT (p = 0.831) showed no significant association.

Conclusions: Denali filters require longer indwelling durations than Cordis filters, with age and DVT location (BKDVT) being critical determinants for Denali, whereas only DVT location affects Cordis. Clinicians should tailor follow-up schedules and prioritize early retrieval for Cordis filters to reduce complications. These findings underscore the importance of individualized IVCF management based on filter type and thrombus location.