Modified microcatheter first-pass effect: Enhancing diagnostic accuracy and treatment strategies for ICAS in acute...

To evaluate the effectiveness of the modified microcatheter first-pass effect in guiding treatment decisions for ICAS-related occlusions during endovascular therapy (EVT) for AIS.

This study analyzed data from 31 AIS patients with a positive modified microcatheter first-pass effect from the OCEAN-AIS-EVT REGISTRY collected between July 2023 and January 2024. We evaluated diagnostic accuracy, procedural efficiency, recanalization rates, and safety.

ICAS was confirmed in all cases. The median age was 69 years, with 61.29 % males. The median NIHSS score was 9, and ASPECTS was 9. Stenosis primarily occurred in the M1 segment of the middle cerebral artery (74.19 %). The median puncture-to-recanalization time was 18.92 min. Successful recanalization (eTICI grade 3) was achieved in 87.10 % of cases. Post-procedural hemorrhage occurred in 12.90 % of patients, with symptomatic hemorrhage in 3.23 %. At 90-day follow-up, 80.64 % had an mRS score of 0-2.

The modified microcatheter first-pass effect may serve as a promising preliminary tool for guiding EVT strategy in ICAS-related AIS. By confirming distal vessel patency, it enables direct angioplasty without prior thrombectomy, simplifying the procedure and reducing mechanical manipulation. While this exploratory approach has shown potential to enhance treatment efficiency and improve clinical outcomes, larger-scale prospective studies are needed to further validate these preliminary findings.