Abstract P507: Clot Ingestion Leads to the Highest First Pass Complete Recanalization Rates in a Human Brain Model of Large Vessel Occlusion Stroke
Introduction: Suction catheters and stent retrievers are based on the classical paradigm of “en bloc” removal of emboli by generation of tensile forces by vacuum or device withdrawal. However, in this process emboli elongate and fracture leading to fragmentation. Fragments can migrate downstream or remain impacted in the arterial wall resulting in a residual occlusion. Hypothesis: Clot ingestion is biomechanically superior to “en bloc” removal and leads to higher recanalization rates with less complications. Methods: To test this hypothesis, we present a hybrid test bed consisting of pressurized human brains which was developed and validated for large vessel occlusion (LVO) and revascularization. We fabricated 3 types of representative embolus analogs (EAs) (elastic, fragment-prone and stiff) and recreated 105 LVO in twenty-four fresh human brains with the vasculature connected to an hydraulic system to mimic physiological flow and pressures. Recanalization was attempted in 61 LVO cases by Direct Aspiration (DA) using an 068 catheter and in 44 LVO cases combining Stent Retriever with Aspiration (SR+A). Rates of successful recanalization (SR, Grade 2b or higher) and complete recanalization (CR, Grade 2c or higher) were measured. Up to 4 attempts were done before declaring a failure (Grade 2a or lower). Results: DA resulted in 90% of SR, 79% of CR, 61% of first pass SR and 49% of first pass CR. SR+A resulted in 34% of SR, 34% of CR, 23% of first pass SR and 14% of first pass CR. Elastic EA were associated with 88% of SR, 85% of CR, 61% of first pass SR and 52% of first pass CR. Stiff EAs were associated with 64% of SR, 64% of CR, 36% of first pass SR and 36% of first pass CR. Fragment-prone EAs were associated with 64% of SR, 40% of CR, 38% of first pass SR and 21% of first pass CR. Conclusion: Clot ingestion is biomechanically superior to “en bloc” removal and leads to the highest rates of SR, CR and first pass recanalization. DA achieves higher recanalization rates than SR+A. Elastic clots are associated with the highest rates or recanalization, followed by stiff clots and finally by fragment-prone clots.