P134 Comparative in vitro analysis of adjunctive intra-arterial lytics on human blood clots

<h3>Introduction</h3> Complete recanalization after endovascular treatment (EVT) in stroke is linked to better clinical outcomes. Adjunctive Intraarterial lytics might enhance recanalization rates. <h3>Aim of Study</h3> We aimed to compare the in vitro effect of rt-PA and Tirofiban on clots retrieved during EVT. <h3>Methods</h3> Clots retrieved during EVT were divided into two fragments (or three in cases in which control test was performed). Blood samples were collected and plasma was separated and mixed with 5 mL of Tirofiban, rt-PA or physiological saline in controls. Each clot fragment was embolized in a 3D printed arterial model connected to a flow pump creating a closed circuit where the study solution was circulated for 5 minutes. Clots were weighted before and after experiments. Additionally, in a subset of clots initially treated with tPA, the experiment was repeated consecutively with Tirofiban to assess the combined effect of the two drugs. <h3>Results</h3> From May 2023 to March 2024, 45 clots (110 experiments) were tested. In the control cases (n=10) median weight reduction was 5.7% as compared to 20.4% with tPA (p&lt;0.01) and 21.1% with Tirofiban (p&lt;0.01). Clots treated with both drugs showed 40.3% weight reduction, significantly higher than individual treatments (p&lt;0.01) <h3>Conclusion</h3> In our experimental design, both rt-PA and Tirofiban induced a significant clot weight reduction. Sequential drug administration resulted in a significantly higher lytic effect. Further studies should validate the safety and efficacy of intraarterial lysis adjunctive to EVT. <h3>Disclosure of Interest</h3> no.