Bio-Inspired Micro-Fin-Assisted Multi-Modal Vascular Intervention.

Interventional procedures are essential in vascular medicine, but precise navigation through tortuous vasculature remains difficult due to the limited steerability of guidewires in complex anatomical regions. Magnetic guidewires have been developed to address this limitation, yet they typically depend on accurate field control using robotic-arm-mounted magnets or electromagnets, which constrains their use in space-limited intervention room. Here, a magnetic guidewire with a micro-fin-integrated tip for multimodal vascular intervention is introduced. The micro-fins respond to external magnetic fields and generate additional torques through fluid drag and vessel wall contact forces, supplementing the magnetic torque and gradient forces of conventional designs. This combination enables the guidewire to pass bifurcations under lower magnetic field strength, reduced from 34 to 15 mT in the trials, and to tolerate external field misalignments up to 45 degrees. The micro-fin structure also permits bidirectional crawling and self-correction from buckling. In vivo testing in rabbit vascular models shows the device reduced time by ≈50% compared to a commercial guidewire, even when the magnetic field is manually applied, and allows full access to major arteries within 1 min. These findings demonstrate that micro-fins integration provides advantages that improve the control and efficiency of magnetic guidewires in complex vascular environments.