IMPORTANCE Direct transfer to angiography suite (DTAS) for patients with suspected large vessel occlusion (LVO) stroke has been described as an effective and safe measure to reduce workflow time in endovascular treatment (EVT). However, it is unknown whether DTAS improves long-term functional outcomes.OBJECTIVE To explore the effect of DTAS on clinical outcomes among patients with LVO stroke in a randomized clinical trial. DESIGN, SETTING, AND PARTICIPANTSThe study was an investigator-initiated, single-center, evaluator-blinded randomized clinical trial. Of 466 consecutive patients with acute stroke screened, 174 with suspected LVO acute stroke within 6 hours of symptom onset were included. Enrollment took place from September 2018 to November 2020 and was stopped after a preplanned interim analysis. Final follow-up was in February 2021.INTERVENTIONS Patients were randomly assigned (1:1) to follow either DTAS (89 patients) or conventional workflow (85 patients received direct transfer to computed tomographic imaging, with usual imaging performed and EVT indication decided) to assess the indication of EVT. Patients were stratified according to their having been transferred from a primary center vs having a direct admission. MAIN OUTCOMES AND MEASURESThe primary outcome was a shift analysis assessing the distribution of the 90-day 7-category (from 0 [no symptoms] to 6 [death]) modified Rankin Scale (mRS) score among patients with LVO whether or not they received EVT (modified intention-to-treat population) assessed by blinded external evaluators. Secondary outcomes included rate of EVT and door-to-arterial puncture time. Safety outcomes included 90-day mortality and rates of symptomatic intracranial hemorrhage. RESULTSIn total, 174 patients were included, with a mean (SD) age of 73.4 (12.6) years (range, 19-95 years), and 78 patients (44.8%) were women. Their mean (SD) onset-to-door time was 228.0 (117.9) minutes, and their median admission National Institutes of Health Stroke Scale score was 18 (interquartile range [IQR], 14-21). In the modified intention-to-treat population, EVT was performed for all 74 patients in the DTAS group and for 64 patients (87.7%) in the conventional workflow group (P = .002). The DTAS protocol decreased the median door-to-arterial puncture time (18 minutes [IQR, 15-24 minutes] vs 42 minutes [IQR, 35-51 minutes]; P < .001) and door-to-reperfusion time (57 minutes [IQR, vs 84 minutes [IQR, 63-117 minutes]; P < .001). The DTAS protocol decreased the severity of disability across the range of the mRS (adjusted common odds ratio, 2.2; 95% CI, 1.2-4.1; P = .009). Safety variables were comparable between groups. CONCLUSIONS AND RELEVANCEFor patients with LVO admitted within 6 hours after symptom onset, this randomized clinical trial found that, compared with conventional workflow, the use of DTAS increased the odds of patients undergoing EVT, decreased hospital workflow time, and improved clinical outcome.

Background An increased rate of thrombotic events has been associated to Coronavirus Disease 19 (COVID-19) with a variable rate of acute stroke. Our aim is to uncover the rate of acute stroke in COVID-19 patients and identify those cases in which a possible causative relationship could exist. Methods We performed a single-center analysis of a prospective mandatory database. We studied all patients with confirmed COVID-19 and stroke diagnoses from March 2 nd to April 30 th . Demographic, clinical, and imaging data were prospectively collected. Final diagnosis was determined after full diagnostic work-up unless impossible due to death. Results Of 2050 patients with confirmed SARS-CoV-2 infection, 21 (1.02%) presented an acute ischemic stroke 21 and 4 (0.2%) suffered an intracranial hemorrhage. After the diagnostic work-up, in 60.0% ischemic and all hemorrhagic strokes patients an etiology non-related with COVID-19 was identified. Only in 6 patients the stroke cause was considered possibly related to COVID-19, all of them required mechanical ventilation before stroke onset. Ten patients underwent endovascular treatment; compared with patients who underwent EVT in the same period, COVID-19 was an independent predictor of in-hospital mortality (50% versus 15%; Odds Ratio, 6.67; 95% CI, 1.1-40.4; p 0.04). Conclusions The presence of acute stroke in patients with COVID-19 was below 2% and most of them previously presented established stroke risk factors. Without other potential cause, stroke was an uncommon complication and exclusive of patients with a severe pulmonary injury. The presence of COVID-19 in patients who underwent EVT was an independent predictor of in-hospital mortality.

Background and Purpose: Different studies have pointed that CT perfusion (CTP) could overestimate ischemic core in early time window. We aim to evaluate the influence of time and collateral status on ischemic core overestimation. Methods: Retrospective single-center study including patients with anterior circulation large-vessel stroke that achieved reperfusion after endovascular treatment. Ischemic core and collateral status were automatically estimated on baseline CTP using commercially available software. CTP-derived core was considered as tissue with a relative reduction of cerebral blood flow <30%, as compared with contralateral hemisphere. Collateral status was assessed using the hypoperfusion intensity ratio (defined by the proportion of the time to maximum of tissue residue function >6 seconds with time to maximum of tissue residue function >10 seconds). Final infarct volume was measured on 24 to 48 hours noncontrast CT. Ischemic core overestimation was considered when CTP-derived core was larger than final infarct. Results: Four hundred and seven patients were included in the analysis. Median CTP-derived core and final infarct volume were 7 mL (interquartile range, 0–27) and 20 mL (interquartile range, 5–55), respectively. Median hypoperfusion intensity ratio was 0.46 (interquartile range, 0.23–0.59). Eighty-three patients (20%) presented ischemic core overestimation (median overestimation, 12 mL [interquartile range, 41–5]). Multivariable logistic regression analysis adjusted by CTP-derived core and confounding variables showed that poor collateral status (per 0.1 hypoperfusion intensity ratio increase; adjusted odds ratio, 1.41 [95% CI, 1.20–1.65]) and earlier onset to imaging time (per 60 minutes earlier; adjusted odds ratio, 1.14 [CI, 1.04–1.25]) were independently associated with core overestimation. No significant association was found with imaging to reperfusion time (per 30 minutes earlier; adjusted odds ratio, 1.17 [CI, 0.96–1.44]). Poor collateral status influence on core overestimation differed according to onset to imaging time, with a stronger size of effect on early imaging patients( P interaction <0.01). Conclusions: In patients with large-vessel stroke that achieve reperfusion after endovascular therapy, poor collateral status might induce higher rates of ischemic core overestimation on CTP, especially in patients in earlier window time. CTP reflects a hemodynamic state rather than tissue fate; collateral status and onset to imaging time are important factors to consider when estimating core on CTP.

Background and Purpose— Despite recanalization, almost 50% of patients undergoing endovascular treatment (EVT) experience poor outcome. We aim to evaluate the value of computed tomography perfusion as immediate outcome predictor postendovascular treatment. Methods— Consecutive patients receiving endovascular treatment who achieved recanalization (modified Thrombolysis in Cerebral Ischemia [mTICI] 2a-3) underwent computed tomography perfusion within 30 minutes from recanalization (CTPpost). Hypoperfusion was defined as the Tmax>6 second volume; hyperperfusion as visually increased cerebral blood flow/cerebral blood volume with reduced Tmax compared with unaffected hemisphere. Dramatic clinical recovery (DCR) was defined as 24-hour National Institutes of Health Stroke Scale score ≤2 or ≥8 points drop. Delayed recovery was defined as no-DCR with favorable outcome (modified Rankin Scale score 0–2) at 3 months. Results— We included 151 patients: median National Institutes of Health Stroke Scale score 16 (interquartile range, 10–21), median admission ASPECTS 9 (interquartile range, 8–10). Final recanalization was the following: mTICI2a 11 (7.3%), mTICI2b 46 (30.5%), and mTICI3 94 (62.3%). On CTPpost, 80 (52.9%) patients showed hypoperfusion (median Tmax>6 seconds: 4 cc [0–25]) and 32 (21.2%) hyperperfusion. There was an association between final TICI and CTPpost hypoperfusion(median Tmax>6: 91 [56–117], 15 [0–37.5], and 0 [0–7] cc, for mTICI 2a, 2b, and 3, respectively, P <0.01). Smaller hypoperfusion volumes on CTPpost were observed in patients with DCR (0 cc [0–13] versus non-DCR 8 cc [0–56]; P <0.01) or favorable outcome (modified Rankin Scale score 0–2: 0 cc [0–13] versus 7 [0–56] cc; P <0.01). No associations were detected with hyperperfusion pattern. An hypoperfusion volume <3.5 cc emerged as independent predictor of DCR (OR, 4.1 [95% CI, 2.0–8.3]; P <0.01) and 3 months favorable outcome (OR, 3.5 [95% CI, 1.6–7.8]; P <0.01). Conclusions— Hypoperfusion on CTPpost constitutes an immediate accurate surrogate marker of success after endovascular treatment and identifies those patients with delayed recovery and favorable outcome.

BackgroundIn patients with stroke, current guidelines recommend non-invasive vascular imaging to identify intracranial vessel occlusions (VO) that may benefit from endovascular treatment (EVT). However, VO can be missed in CT angiography (CTA) readings. We aim to evaluate the impact of consistently including CT perfusion (CTP) in admission stroke imaging protocols.MethodsFrom April to October 2020 all patients admitted with a suspected acute ischemic stroke underwent urgent non-contrast CT, CTA and CTP and were treated accordingly. Hypoperfusion areas defined by time-to-maximum of the tissue residue function (Tmax) >6 s, congruent with the clinical symptoms and a vascular territory, were considered VO (CTP-VO). In addition, two experienced neuroradiologists blinded to CTP but not to clinical symptoms retrospectively evaluated non-contrast CT and CTA to identify intracranial VO (CTA-VO).ResultsOf the 338 patients included in the analysis, 157 (46.5%) presented with CTP-VO (median Tmax >6s: 73 (29–127) mL). CTA-VO was identified in 83 (24.5%) of the cases. Overall CTA-VO sensitivity for the detection of CTP-VO was 50.3% and specificity was 97.8%. Higher hypoperfusion volume was associated with increased CTA-VO detection (OR 1.03; 95% CI 1.02 to 1.04). EVT was performed in 103 patients (30.5%; Tmax >6s: 102 (63–160) mL), representing 65.6% of all CTP-VO. Overall CTA-VO sensitivity for the detection of EVT-VO was 69.9% and specificity was 95.3%. Among patients who received EVT, the rate of false negative CTA-VO was 30.1% (Tmax >6s: 69 (46–99.5) mL).ConclusionSystematically including CTP in acute stroke admission imaging protocols may increase the diagnosis of VO and rate of EVT.