Abstract 84: Collaterals Drive Reperfusion in Stratis

Background: Collateral circulation to the ischemic territory is a pivotal factor in outcomes after acute ischemic stroke. Extent of angiographic collaterals prior to endovascular therapy has been linked with reperfusion in previous trials, yet the mechanism remains unclear. We analyzed whether downstream collateral grade influences the pace and degree of ultimate reperfusion. Methods: The angiography dataset collated by the STRATIS Core Lab was analyzed to relate the grade of collateral circulation (ASITN) with adjudicated procedural time metrics to exact time of first TICI ≥ 2A and with the final eTICI score, delineating reperfusion into 7 distinct categories. Results: Collateral grade on routine angiography injections was available in 574/984 (58%) of STRATIS subjects (age 67.5 ± 15.1, 47% women, baseline NIHSS 16.8 ± 5.5). Collaterals included 203/574 (35.4%) with ASITN 3-4, 291/574 (50.7%) ASITN 2 and 80/574 (13.9%) ASITN 0-1. TICI ≥ 2A was achieved at 32.4 ± 23.5 minutes from angiography start and 26...