Introduction Mechanical thrombectomy (MT) has become a first-line treatment for acute ischemic stroke. Several techniques combining stent retrievers (SR) and distal aspiration catheters (DAC) have been described.

Aim of Study We aimed to characterize the efficacy of two commonly used techniques according to clot characteristics.

Methods Soft (stiffness = 95.77±5.80 kPa) or stiff (205.63±6.70 kPa) synthetic clots (3x10 mm and 2x10 mm, respectively) were embolized to the distal M1 segment of the middle cerebral artery (MCA) in an in vitro model. The retrieval technique was randomly allocated (1:1): SAVE (partial retraction of SR into DAC) vs. Solumbra (total retraction). Primary endpoint was the percentage of first-pass recanalization (%FPR). Secondary endpoints were periprocedural distal embolization measures.

Results A total of 130 MTs were performed (50 for soft clots and 15 for stiff clots per arm). Overall, the rate of FPR was 35% with Solumbra and 15% with SAVE (p<0.01). For stiff clots, the FPR was equal for both methods (27%; p=1.00). With soft clots, FPR was higher with Solumbra (38%) than with SAVE (12%; p<0.01). When using soft clots, maximum embolus size (1.19±0.9 mm vs. 2.16±1.48 mm; p<0.01) and total area of emboli (1.82±2.73 vs. 3.34±3.2; p=0.01) were also lower with Solumbra than with SAVE.

Conclusion Clot characteristics may influence the efficacy of the thrombectomy technique. In occlusions caused by soft clots, complete retrieval into the DAC achieved higher rates of FPR and lower embolization.

Disclosure of Interest Magda Jablonska has nothing to disclose.

Jiahui Li has nothing to disclose.

Riccardo Tiberi has nothing to disclose.

Pere Canals has nothing to disclose.

Alejandro Tomasello reports receiving consulting fees from Anaconda Biomed, Balt, Medtronic, MicroVention, Cerus, Merlin Medical, and Stryker.

Marc Ribo is a consultant for Medtronic, Cerenovus, Vesalio.