High thrombus density ratio on CT venography is associated with inferior vena cava filters trapped embolus in patients with deep vein thrombosis.

OBJECTIVE

Defining the appropriate use of retrievable inferior vena cava filters (RIVCF) in patients with deep vein thrombosis (DVT) remains significant clinical need. This study aimed to investigate the association between thrombus density on computed tomography venography (CTV) and RIVCF-trapped embolus to further identify DVT patients who may benefit from RIVCF implantation.

MATERIALS AND

METHODS

Between 2019 and 2023, 91 DVT patients with RIVCF implantation were prospectively recruited. CTV was performed for all patients. Based on the presence of RIVCF-trapped embolus at filter retrieval, patients were divided into the no-embolus group and the embolus group. The thrombus density ratio was compared between the two groups. Univariate and multivariate logistic regression models and receiver operating characteristic curve analyses were used to identify the association between thrombus density ratio and RIVCF-trapped embolus.

RESULTS

RIVCF-trapped embolus occurred in 55 patients (60 %). The thrombus density ratio was significantly higher in the embolus group than the no-embolus group (46.23 ± 0.1 % vs. 55 ± 0.08 %, p < 0.001). Logistic regression analysis showed that a high thrombus density ratio was associated with thrombus detachment (OR = 2.36, 95 % CI: 1.29-4.29; p = 0.005). The AUC value of the logistic regression model combined with thrombus density ratio and D-dimer for predicting RIVCF-trapped embolus was 0.882 (p < 0.001), and the thrombus density ratio was 0.841 (95 % CI: 0.75-0.92; p < 0.001).

CONCLUSION

CT-based high thrombus density ratio could predict RIVCF-trapped embolus in DVT patients, indicating that those patients require aggressive RIVCF placement.

CLINICAL RELEVANCE STATEMENT: CT-based high thrombus density ratio was associated with RIVCF-trapped embolus, which can be a potential imaging marker to identify patients who may benefit from RIVCF implantation and may contribute to future improvements of RIVCF application guidelines.