Endovascular treatment for patients with acute stroke who have a large ischemic core and large mismatch imaging profile

Abstract

IMPORTANCE Endovascular therapy (ET) is typically not considered for patients with large baseline ischemic cores (irreversibly injured tissue). Computed tomographic perfusion (CTP) imagingmay identify a subset of patients with large ischemic cores who remain at risk for significant infarct expansion and thus could still benefit from reperfusion to reduce their degree of disability. OBJECTIVE To compare the outcomes of patients with large baseline ischemic cores on CTP undergoing ET with the outcomes of matched controls who had medical care alone. DESIGN, SETTING, AND PARTICIPANTS A matched case-control study of patients with proximal occlusion after stroke (intracranial internal carotid artery and/or middle cerebral arteryM1 and/or M2) on computed tomographic angiography and baseline ischemic core greater than 50 mL on CTP at a tertiary care center from May 1, 2011, through October 31, 2015. Patients receiving ET and controls receiving medical treatment alone were matched for age, baseline ischemic core volume on CTP, and glucose levels. Baseline characteristics and outcomes were compared. MAIN OUTCOMES AND MEASURES The primary outcome measurewas the shift in the degree of disability among the treatment and control groups as measured by the modified Rankin Scale (mRS) (with scores ranging from 0 [fully independent] to 6 [dead]) at 90 days. RESULTS Fifty-six patients were matched across 2 equally distributed groups (mean [SD] age, 62.25 [13.92] years for cases and 58.32 [14.79] years for controls; male, 13 cases [46%] and 14 controls [50%]). Endovascular therapy was significantly associated with a favorable shift in the overall distribution of 90-day mRS scores (odds ratio, 2.56; 95%CI, 2.50-8.47; P = .04), higher rates of independent outcomes (90-day mRS scores of 0-2, 25%vs 0%; P = .04), and smaller final infarct volumes (mean [SD], 87 [77] vs 242 [120] mL; P < .001). One control (4%) and 2 treatment patients (7%) developed a parenchymal hematoma type 2 (P > .99). The rates of hemicraniectomy (2 [7%] vs 6 [21%]; P = .10) and 90-day mortality (7 [29%] vs 11 [48%]; P = .75) were numerically lower in the intervention arm. Sensitivity analysis for patients with a baseline ischemic core greater than 70 mL (12 pairs) revealed a significant reduction in final infarct volumes (mean [SD], 110 [65] vs 319 [147] mL; P 3) at 90 days. CONCLUSIONS AND RELEVANCE In properly selected patients, ET appears to benefit patients with large core and large mismatch profiles. Future prospective studies are warranted.