Magnetoelastic Vascular Grafts

PROJECT SUMMARY Vascular grafts, which are used to replace, bypass, or repair diseased blood vessels in approximately 3 million surgeries each year, play a crucial role in various medical procedures. However, stenosis remains a significant issue of post-implantation, with nearly 40% of grafts experiencing reduced patency within 2 years. This high incidence of stenosis and its life-threatening complications highlight the urgent need for continuous monitoring of vascular graft patency. However, existing imaging methods for assessing vascular graft stenosis, including X- ray angiography, magnetic resonance imaging, and Doppler ultrasound, are unsuitable for continuous monitoring due to their dependence on operator-controlled equipment, invasive contrast agents, and/or exposure to ionizing radiation. Vascular graft stenosis often goes undetected until it progresses to complete occlusion, necessitating repeat surgeries. To address this grand challenge, we propose a magnetoelastic vascular graft (MVG) as a transformative platform technology that not only restores blood flow but also enables wireless, real-time, and continuous stenosis diagnosis. Our proposed MVG directly translates hemodynamics into high-fidelity electrical signals, which can be wirelessly transmitted outside the human body. As stenosis changes the hemodynamics by restricting blood flow, further analyzing these received signals by using artificial intelligence (AI) can enable continuous and accurate patency monitoring and timely postoperative complication management. Moreover, the MVG’s hemodynamics-driven working mechanism eliminates the need for external power or frequent interventions, enabling continuous, real-time stenosis monitoring anywhere, anytime. This innovative platform technology stems from PI’s recent discovery of the giant magnetoelastic effect in soft matter (Nat. Mater. 2021; Highlighted by Nature). In our preliminary studies, we successfully fabricated MVGs with scalability and customizability and validated their biocompatibility and stenosis diagnosis capability in both rat and swine models in vivo. To further test our hypothesis, three specific aims are proposed for this R01 Research Project: Aim 1) To optimize the MVG and determine how the degree of stenosis affects sensing signals. Aim 2) To investigate the long-term biosafety and sensing durability of the MVG in rat models. Aim 3) To investigate the long-term stenosis monitoring in swine models. To achieve these proposed aims, we have assembled a multidisciplinary team with complementary expertise, including PI Prof. Jun Chen (Ph.D., leading expert in soft magnetoelastic bioelectronics), Co-Is Prof. Song Li (Ph.D., expert in vascular tissue engineering), and Prof. Geoffrey Colby (M.D., Ph.D.,16 years of expertise in open microsurgical and endovascular treatments), and Prof. Wei Wang (Ph.D., Fellow of ACM, IEEE, clinical big data analysis), and Consultant Prof. Murray H. Kwon (M.D., MBA, expert cardiothoracic surgeon). Successful deliverables are expected to drive a transformative shift in vascular disease management, enhancing both quality of life and human longevity.