A miniature endovascular soft robot for active blood flow regulation in occluded vessels.

Abstract

Blood flow abnormalities in occluded or narrowed vessels limit drug delivery and contribute to recurrent vascular disease. Existing endovascular or pharmacological approaches do not directly address impaired local flow. Here we propose a miniature endovascular soft robot for active blood flow regulation and enhanced fluid exchange and drug transport in occluded vessels. The soft robot integrates a magnetic body for navigation with cilia that generate metachronal waves to drive the flow. Navigation and flow regulation are decoupled, allowing positioning at target sites followed by local flow enhancement. We investigate the flow regulation mechanism and optimize the structural parameters of the cilia carpet. We validate flow regulation in different vessel phantoms with biologically relevant conditions and in large animal studies. The system restores flow in occluded branches and improves delivery of therapeutic agents, accelerating clot dissolution with reduced residual obstruction and shorter recanalization time both in vitro and in vivo. This technology allows the local modulation of vascular flow, supporting more effective and controlled endovascular therapies.