Introduction Clot specimens retrieved with mechanical thrombectomy have been shown to have dense meshes of neutrophil extracellular traps (NETs) on histology. Currently, there are no surface modifications for stent-retrievers.

Aim of Study We hypothesized that stent-retrievers NET-binding coatings will anchor clots and reduce distal emboli.

Methods Nickel-titanium plates with 15 different coatings, were exposed to NETs and human blood in vitro. The amount of chromatin and platelet binding was measured with immunohistochemistry. The two best candidate coatings were then applied to the Solitaire device and tested in a simulated use experiment of MCA occlusion. The two coated devices and two control devices were block randomized for mechanical thrombectomy with 10 replicate experiments. Effluent was collected for emboli analysis.

Results Two compounds with increased affinity for chromatin and reduced affinity for platelet binding were tested in the simulated use experiment. Results showed that the control devices had similar numbers of total fragmented emboli >200µm. Both NETs-binding coatings had a statistically significant reduction in total clot fragments released during MT as compared to bare metal stent (p=0.042). Final complete reperfusion was equivalent for all devices but in 70% of bare metal stent thrombectomies the clot became dislodged in the ICA which was reduced with the NET-binding coated devices.

Conclusion Coating technologies targeting NETs of clots causing large vessel occlusion lead to fewer clot fragments during stent-retriever thrombectomy and reduce the effect of clot ‘rolling’ off the stent.

Disclosure of Interest CS, GC, MA and AN are the inventors of a pending patent related to this work (WO2021EP64257). GC and AN are the scientific co-founders of a company related to this work (KAPTO Medical). VA,EP, ME,CR,GI,MM,RR: Nothing to disclose

MG: No relevant disclosures.