Blood clot fracture properties are dependent on red blood cell and fibrin content

Thrombus fragmentation during endovascular stroke treatment, such as mechanical thrombectomy, leads to downstream emboli, resulting in poor clinical outcomes. Clinical studies suggest that risk is dependent on clot composition. This current study presents the first experimental characterization of composition-dependent fracture properties blood clots, addition development a predictive model for fragmentation. A bespoke test-rig and compact tension specimen fabrication has been developed measure toughness thrombus material. Fracture tests are performed three physiologically relevant compositions: high-fibrin made from 5% haematocrit (H) mixture, medium-fibrin form 20% H low-fibrin 40% mixture. observed significantly increase with increasing fibrin content, i.e. red cell-rich clots more prone tear loading compared fibrin-rich clots. Results also reveal behaviour analogues different compression tension. Finite element cohesive zone modelling experiments show fibres become highly aligned direction perpendicular crack propagation, providing significant toughening mechanism. The results presented this provide key importance next-generation thrombectomy devices strategies. provides characterisation entails novel techniques testing specimens. develops models initiation propagation resistance higher than cell rich Simulations stretching realignment network should be included material order accurately replicate compression-tension asymmetry enhanced toughness. have potentially important implications terms secondary embolization procedures.