Bismuth Nanoparticle and Polyhydroxybutyrate Coatings Enhance the Radiopacity of Absorbable Inferior Vena Cava Filters for Fluoroscopy-Guided Placement and Longitudinal Computed Tomography Monitoring in Pigs

Abstract

Inferior vena cava filters (IVCFs) constructed with poly-p-dioxanone (PPDO) are promising alternatives to metallic filters and their associated risks and complications. Incorporating high-Z nanoparticles (NPs) improves PPDO IVCFs' radiopacity without adversely affecting their safety or performance. However, increased radiopacity from these studies are insufficient for filter visualization during fluoroscopy-guided PPDO IVCF deployment. This study focuses on the use of bismuth nanoparticles (BiNPs) as radiopacifiers to render sufficient signal intensity for the fluoroscopy-guided deployment and long-term CT monitoring of PPDO IVCFs. The use of polyhydroxybutyate (PHB) as an additional layer to increase the surface adsorption of NPs resulted in a 2-fold increase in BiNP coating (BiNP−PPDO IVCFs, 3.8%; BiNP−PPDO + PHB IVCFs, 6.2%), enabling complete filter visualization during fluoroscopy-guided IVCF deployment and, 1 week later, clot deployment. The biocompatibility, clot-trapping efficacy, and mechanical strength of the control PPDO (load-at-break, 6.23 ± 0.13 kg), BiNP−PPDO (6.10 ± 0.09 kg), and BiNP−PPDO + PHB (6.15 ± 0.13 kg) IVCFs did not differ significantly over a 12-week monitoring period in pigs. These results indicate that BiNP−PPDO + PHB can increase the radiodensity of a novel absorbable IVCF without compromising device strength. Visualizing the device under conventional radiographic imaging is key to allow safe and effective clinical translation of the device.

Nano‐embedded medical devices and delivery systems in interventional radiology

“…Current vascular medical devices with nanotechnology applications. Different nanoparticles with varying size, morphology, physical, and chemical properties have been explored in use with existing medical devices and has been particularly useful in diagnostic and vascular radiology applications such as vascular access (Dror et al, 2009; Mannarino et al, 2020; Perez, Damasco, et al, 2021), vascular stents (Hou et al, 2020; Song et al, 2021; Zhao et al, 2018), and inferior vena cava filters (Damasco et al, 2022; Huang et al, 2020; Tian et al, 2017). …”

“…AuNP‐infused PPDO has been effectively tested in a swine model and successfully demonstrated radiopacity, robust mechanical strength, and biocompatibility (Huang et al, 2020; Tian et al, 2017). Bismuth NP (BiNP)–coated PPDO filters showed higher radiopacity than AuNP and even higher radiopacity when reinforced with polyhydroxybutyrate (PHB), which allows these bi‐coated IVCFs to be imaged on fluoroscopy, which is not possible with AuNP‐PPDO (Damasco et al, 2022). Similar to AuNP, BiNP with or without PHB had no effect on the biocompatibility, mechanical strength, and toxicity of the IVCF.…”

“…Comparison radiopacity of bare, AuNP‐, and BiNP‐coated poly‐p‐dioxanone (PPDO) filters in photo, micro‐CT(mCT), and in vivo CT imaging in pigs (adapted from the studies of Huang et al (2017) for bare PPDO, Huang et al (2020) for PPDO‐Au, Damasco et al (2022) for PPDO‐Bi). PPDO filters have significantly improved radiopacity with the addition of Au and Bi nanoparticles.…”

The application of inferior vena cava filters in orthopaedics and current research advances

“…The development of organic polymer compounds with enhanced imaging capabilities may further expand the use of biodegradable scaffolds in tissue engineering. The main methods currently available are the blending of 2,3,5-triiodobenzoic acid (TIBA) ( Singhana et al, 2015 ; Zhao et al, 2020 ), gold nanoparticles (AuNPs) ( Tian et al, 2017 ; Tian et al, 2018 ; Huang et al, 2020 ) or bismuth nanoparticles (BiNPs) ( Perez et al, 2021 ; Damasco et al, 2022 ) into PPDO to increase its imaging capacity.…”

Rosuvastatin-Eluting Gold Nanoparticle-Loaded Perivascular Implantable Wrap for Enhanced Arteriovenous Fistula Maturation in a Murine Model

“…The safety and efficacy of AuNPs for intravascular graft monitoring have been demonstrated in a previous study aimed at monitoring the precise positioning and integrity of inferior vena cava filters using standard radiographic and computed tomography imaging modalities (10). The incorporation of radiopaque nanoparticles into existing, physiologically compatible polymers has proven beneficial for other commonly used vascular devices, as seen with the increased visibility of resorbable, polydioxanone polymer inferior vena cava filters when implanted with Au and bismuth NPs (11–14). For this study, the supplementation of bioabsorbable PCL wraps with AuNPs can offer the advantage of monitoring the effects of local mechanical and pharmacological therapy embedded within the vascular graft.…”