Preclinical evaluation of a novel endovascular thrombectomy device in a modified swine model for iliac vein thrombosis

Abstract

Objective: To evaluate the safety and efficacy of a novel endovascular thrombectomy device in a modified swine model of iliac vein thrombosis. Methods: A modified swine model for iliac vein thrombosis was created using proximal‒distal balloon occlusion combined with autologous venous thrombus and thrombin injections. The safety and efficacy of the newly developed Zylox endovascular thrombectomy system were evaluated in this animal model and its performance was compared with that of the AcoStream aspiration thrombectomy device. Results: Bilateral iliac vein thrombosis models were successfully created in 12 swine, with 23 iliac veins used for device testing and one for anatomical observation. The thrombus length in the Zylox group was greater than in the AcoStream group (98.42 ± 17.56 mm vs. 84.12 ± 13.30 mm), while thrombus scores were not significantly different between the two groups. Although Grade I thrombus clearance was achieved in all iliac veins in both groups, blood loss in the Zylox group was significantly less than in the AcoStream group (81.09 ± 27.26 ml vs. 162.50 ± 61.96 ml, P < 0.001). Three swine (6 iliac veins) in each group underwent repeat venography evaluations 28 days postthrombectomy, showing that all the veins were patent without any rethrombosis. Histopathologic evaluation immediately and 28 days postthrombectomy revealed no differences between the two groups. No complications or deaths occurred in the swine during the entire process. Conclusion: The current modified swine model is stable, reproducible, and appropriate for testing endovascular devices. This study preliminarily verified the safety and efficacy of the Zylox thrombectomy system for thrombus removal in this animal model and demonstrated its advantage in controlling blood loss. Future randomized controlled trials in humans are needed to further verify the safety and efficacy of the device.

Keywords

• Swine model
• Deep venous thrombosis
• Thrombectomy
• Endovascular therapy
• Pharmacomechanical thrombolysis