Novel synthetic clot analogs for in-vitro stroke modelling

Abstract

Purpose The increased demand for training of mechanical thrombectomy in ischemic stroke and development of new recanalization devices urges the creation of new simulation models both for training and device assessment. Clots properties have shown to play a role in procedural planning and thrombectomy device effectiveness. In this study, we analyzed the characteristics and applicability of completely synthetic, animal-free clots in the setting of an in-vitro model of mechanical thrombectomy for training and device assessment. Methods Synthetic clots based on agarose (n = 12) and silicone (n = 11) were evaluated in an in-vitro neurointervention simulation of mechanical thrombectomy with clot extraction devices. Calcified clots of mixed nature were simulated with addition of 3D printed structures. 9 clots were excluded due to insufficient vessel occlusion and failure to integrate with clot extraction device. Synthetic thrombi were characterized and compared using a categorical score-system on vessel occlusion, elasticity, fragmentation, adherence and device integration. Results Both agarose-based and silicone-based clots demonstrated relevant flow arrest and a good integration with the clot extraction device. Silicone-based clots scored higher on adherence to the vessel wall and elasticity. Conclusion Selected synthetic clots can successfully be implemented in an in-vitro training environment of mechanical thrombectomy. The clots’ different properties might serve to mimic fibrin-rich and red blood cell-rich human thrombi.

Study and simulation of thrombus properties

“…Therefore, the frequent diseases of arterial thrombosis are acute myocardial infarction, acute ischemic stroke and pulmonary embolism [9]. In terms of the formation mechanism, a large amount of evidence shows [10] that arterial thrombosis is an acute attack of chronic vascular disease, and the inflammatory changes of unstable plaques lead to plaque rupture or fissure, which further stimulates thrombosis. At the cellular level, arterial thrombosis is mainly caused by platelet activation and then the aggregation of other components, which are usually with atherosclerotic lesions [11].…”

“…Guerreiro et al [10] described the first completely synthetic blood clot replacement model consisting mainly of agarose or silica gel, and analyzed the suitability of this clot in the evaluation of mechanical thrombolysis models and devices in vitro. In order to explore the effectiveness of pulsating and constant aspiration in cerebral thrombectomy models, Simon et al [11] cut synthetic polyrethane clot to a specific clot size with a cylindrical template and placed it directly near the catheter tip for aspiration.…”