Microstent

Microstent is a term used for ultrafine intravascular stents designed for the microvasculature and small-diameter lumens in various organs. They aim to scaffold narrow vessels while minimizing flow disturbance and healing disruption. Applications span peripheral, coronary microvasculature, and certain neurovascular contexts, depending on device design and regulatory status.

Most microstents use materials such as nitinol, stainless steel, or cobalt-chromium and may feature thin struts, high flexibility, and either self-expanding or balloon-expandable mechanisms. Coatings can be bare, drug-eluting, or anti-thrombotic; some designs emphasize radiopacity for placement accuracy.

Common indications include disease in distal small-caliber arteries or microchannels where conventional stents are unsuitable. They are used with microcatheter systems and imaging, with selection based on vessel size, lesion length, and risk of vessel injury.

Delivery involves catheter-based navigation to the target lumen and controlled deployment, followed by antiplatelet therapy and imaging verification. Some devices require post-dilation or coating-specific considerations.

Safety considerations include thrombosis, restenosis, fracture, or embolization. Evidence varies by device and indication; many microstents are approved for specific uses in certain regions, while others remain investigational. Long-term data are limited for some applications.

The development of microstents reflects ongoing miniaturization in endovascular therapy, aided by advances in materials, coatings, and delivery systems. Ongoing trials continue to evaluate indications and outcomes.