Abstract W P21: Extent of Reperfusion and Clinical Outcomes After Endovascular Therapy: More is Better

Abstract

Background: Revascularization is critical to the treatment of acute stroke, yet the association between degree of reperfusion and clinical outcome of endovascular therapy has been incompletely characterized. Methods: In a prospectively maintained registry, we analyzed acute ischemic stroke patients treated with endovascular therapy from 2004-2013. Final TICI scores were compared to non-disabled (mRS 0-2), independent (mRS 0-3), and poor (mRS 5-6) outcomes at discharge in a univariate analysis. Multiple regression analysis was performed to separate effects of baseline patient characteristics, stroke severity, complications, and technical aspects of endovascular treatment. To determine the maximal predictive value of the TICI score, the ROC curve for binned combinations of TICI were compared. Results: Of 183 patients, age was mean 68.4 ± 16.9 years, 58% were female, baseline NIHSS was 16.5 ± 6.9, and mean time from stroke onset to groin puncture was 395 ± 378 minutes. At discharge, the rate of freedom from disability (mRS 0-2) was 15%, freedom from dependency (mRS 0-3) 26%, and poor outcome (mRS 5-6) 54%. Any reperfusion (TICI 2a or higher) was achieved in 79% of patients. Substantial reperfusion (TICI 2b or higher) was associated with higher rates of non-disabled (26% vs 4%, p < 0.001) and independent outcome (37% vs 15%, p = 0.001), and reduced poor outcome (42% vs 66%, p = 0.001). In the multivariate analysis, independent predictors of non-disabled outcome included higher TICI (unmodified 5-level score, β = -0.260, p < 0.001), younger age (β = 0.289, p < 0.001), and lower initial NIHSS (β = 0.355, p < 0.001). Trichotomized TICI scores (0-1, 2a, 2b-3) showed substantial power in predicting discharge outcome: mRS 0-2, c-statistic = 0.72; mRS 0-3, c = 0.64; and mRS 5-6, c = 0.64. Conclusions: Clinical outcome is closely related to the degree of reperfusion achieved during endovascular stroke intervention. Age and initial stroke severity additionally help differentiate patients who are more likely to do well from those who will not. Trichotomized TICI scores are highly predictive of functional clinical outcome.