Abstract TMP3: Age-Adjusted Infarct Volume Cut-off For Favorable Outcome After Large Vessel Occlusion Stroke Endovascular Therapy

Abstract

Background: Optimal selection paradigms for large vessel occlusion acute stroke endovascular therapy are yet to be established. Previous studies have shown the benefit of adjusting infarct size to age. We sought to study the impact of age-adjusted final infarct volumes (FIV), a surrogate for pre-reperfusion infarct core, on functional outcomes and determine the ideal thresholds for good outcome discrimination (90-day mRS 0-2). Methods: We reviewed our prospectively collected endovascular database at a tertiary care academic institution between 9/2010- 8/2016. All patients that underwent endovascular therapy for large vessel occlusion anterior circulation acute ischemic stroke were stratified into five age groups: (G1) <50 years, (G2) 50-69, (G3) 70-79 (G4) 80-89 and (G5) ≥90. Baseline, procedural, and radiological characteristics, as well as outcome parameters were compared. FIV was measure on follow-up MRI or CT within 5 days of treatment. : 966 patients were studied (G1:136, G2:408, G3:233, G4:160, G5:29). Overall, the mean FIV was 59.9±79.9mL and 46% had good outcome. Patients with poor outcome had larger FIV in each group (Mean/Median[IQR]) (G1:46.8/29.2[8.7-64.6] vs 145.3/91.5[51.9-223.5], G2:26.9/15.8[7.7-37.2] vs 93.6/68.1[22.2-146.8], G3:26.2/17.6[7.6-34.1] vs 96.1/61.9[25.5-130.9], G4:14.7/8.7[3.9-16.4] vs 60.2/29[13.6-85.2], G5:2.9/1.3[0.6-4.3] vs 58.3/36.6[18.2-91.1], p<0.01 for all). The target FIV cut-off (mL) decreased with increased age: G1:52.4(SE 75%, SP 65%); G2:23.2(SE 75%,SP 64%); G3:24.6(SE 76%,SP 64%); G4:13.4(SE 75%,SP 70%); G5:12.8(SE 79%,SP 100%). In multivariate analysis, after adjusting for age, baseline NIHSS, glucose level, reperfusion status, parenchymal hematoma and FIV, achieving a final infarct volume less than the age-adjusted target was an independent predictor of good outcome (OR:1.94 95%CI [1.06-3.53], p=0.03). Conclusions: Age-adjusted infarct volume represents a strong outcome discriminator substitute and might help refine patient selection for stroke endovascular therapy