Introduction Complete recanalization after endovascular treatment (EVT) in stroke is linked to better clinical outcomes. Adjunctive Intraarterial lytics might enhance recanalization rates.

Aim of Study We aimed to compare the in vitro effect of rt-PA and Tirofiban on clots retrieved during EVT.

Methods 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.

Results 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<0.01) and 21.1% with Tirofiban (p<0.01). Clots treated with both drugs showed 40.3% weight reduction, significantly higher than individual treatments (p<0.01)

Conclusion 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.

Disclosure of Interest no.