Swirl-inducing innovations for preventing vena cava filter blockage: Theoretical and experimental validation

Background: Pulmonary embolism (PE) arising from deep vein thrombosis (DVT) remains a critical clinical concern. Inferior vena cava (IVC) filters can prevent emboli from reaching the pulmonary vasculature, yet they often become occluded, compromising long-term efficacy. Methods: To address this, we developed a novel swirling flow diverter and evaluated its performance using computational fluid dynamics (CFD) in both idealized and patient-specific IVC models, alongside in vitro experiments in a glass-based perfusion system. Key hemodynamic parameters were assessed under varying geometric conditions (pitch, diameter, taper, and placement distance). Results: CFD simulations showed that the helical diverter effectively induces swirling flow, enhancing wall shear stress and accelerating thrombus clearance on the filter. Both idealized and patient-specific models exhibited reduced thrombus retention compared with standard diverters. In vitro experiments supported these findings, revealing decreased flow residence time and lower residual thrombus volume. Conclusions: Collectively, these observations underscore the importance of systematically optimizing diverter geometry to fully harness the benefits of swirling flow for IVCF applications. With further refinements, this novel diverter design could represent a significant step forward in reducing complications and improving long-term patency in venous filtration systems.