Abstract T P25: Poor Collaterals Necessitate Early Reperfusion: Relationship Between Time to Reperfusion, Collateral Flow, and Clinical Outcome
Background: Clinical outcome following reperfusion can be affected by the adequacy of baseline collaterals during endovascular therapy. We examined the relationship between onset-to-reperfusion time (ORT), collateral grade, and clinical outcome with the hypothesis that there is a narrow therapeutic time window for good clinical outcomes in patients having poor collaterals.
Methods: Among 300 patients who underwent endovascular therapy for acute large vessel occlusion in the anterior circulation, we identified 220 patients having a final TICI score of 2 or more. Patients’ collateral grades, using the ASITN/SIR scale on baseline angiography, were dichotomized into poor (0-1) versus partial/complete (2-4). Favorable functional outcome was defined as a 3-month mRS of 0-2.
Results: Angiographic data on collaterals were available for 207/220 patients, with 76 in the poor collateral group and 131 in the partial/complete group. The TICI 2b-3 reperfusion rates were similar between the two groups [51/76 (67%) vs. 89/131 (68%), p=0.902], though functional outcomes were significantly different [35/76 (46%) vs. 81/131 (63%), p=0.027]. In the poor collateral group, the odds of favorable outcome significantly dropped for patients reperfused beyond 6-hour from onset [28/53 (54%) vs. 7/24 (29%); odds ratio 0.35 (95% CI 0.13-0.99); p=0.045], whereas the probability of favorable outcome in partial/complete group was not as influenced by reperfusion beyond the 6-hour time window [56/85 (66%) vs. 25/46 (54%); odds ratio 0.62 (95% CI 0.30-1.29); p=0.195]. In subgroup analysis of the poor collateral group, each 30-minute increase in ORT was associated with a decreased chance of favorable outcome despite reperfusion after adjustment for age, baseline NIHSS score, and baseline ASPECTS score [odds ratio 0.77 (95% CI 0.64-0.93); p=0.006].
Conclusions: Onset-to-reperfusion time in patients with poor collaterals is an another important factor affecting favorable outcome, and future trials would benefit from a non-invasive imaging technique to detect poor collaterals along with a strategy for early reperfusion.
Author Disclosures: Y. Hwang: None. D. Kang: None. Y. Kim: None. Y. Kim: None.
- © 2014 by American Heart Association, Inc.