Development and translation of biodegradable metal stents: from heart to brain

Biodegradable metal stents offer a promising approach for vascular intervention by providing temporary mechanical support and subsequently degrading once healing is complete. While significant progress has been made in cardiovascular applications, their adaptation for cerebrovascular use remains an active area of research. This review systematically examines three key biodegradable metal systems: Fe, Zn and Mg alloys. It traces their development and specific considerations in the transition from cardiac to cerebral indications. Fe-based stents exhibit high mechanical strength but degrade slowly, prompting strategies to accelerate corrosion. Zn-based stents provide a more moderate degradation rate and favorable biocompatibility, yet their neurovascular safety profile requires further assessment. Mg-based stents, which degrade rapidly and may confer neuroprotective benefits, have advanced into clinical use, though controlling their degradation kinetics remains essential. Translating these stents to the delicate and tortuous cerebrovascular environment introduces specific challenges, including the need for enhanced anatomical conformability, mitigation of potential neurotoxicity from degradation byproducts, and reduction of MRI artifacts. Future development will depend on material-specific strategies: accelerating degradation for Fe alloys, refining controlled-release coatings for Zn alloys, and leveraging the neuroprotective potential of Mg alloys. Ultimately, success hinges on optimizing stent degradation and neurovascular compatibility.