CT perfusion may overestimate final infarct core, especially in the early time window. Selecting patients for reperfusion therapies based on the CTP mismatch concept may deny treatment to patients who might still benefit from reperfusion.

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: Determining the size of infarct extent is crucial to elect patients for reperfusion therapies. Computed tomography perfusion (CTP) based on cerebral blood volume may overestimate infarct core on admission and consequently include ghost infarct core (GIC) in a definitive lesional area. Purpose: Our goal was to confirm and better characterize the GIC phenomenon using CTP cerebral blood flow (CBF) as the reference parameter to determine infarct core. Methods: We performed a retrospective, single-center analysis of consecutive thrombectomies of middle cerebral or intracranial internal carotid artery occlusions considering noncontrast CT Alberta Stroke Program Early CT Score ≥6 in patients with pretreatment CTP. We used the RAPID® software to measure admission infarct core based on initial CBF. The final infarct was extracted from follow-up CT. GIC was defined as initial core minus final infarct > 10 mL. Results: A total of 123 patients were included. The median National Institutes of Health Stroke Scale score was 18 (13–20), the median time from symptoms to CTP was 188 (67–288) min, and the recanalization rate (Thrombolysis in Cerebral Infarction score 2b, 2c, or 3) was 83%. Twenty patients (16%) presented with GIC. GIC was associated with shorter time to recanalization (150 [105–291] vs. 255 [163–367] min, p = 0.05) and larger initial CBF core volume (38 [26–59] vs. 6 [0–27] mL, p < 0.001). An adjusted logistic regression model identified time to recanalization < 302 min (OR 4.598, 95% CI 1.143–18.495, p = 0.032) and initial infarct volume (OR 1.01, 95% CI 1.001–1.019, p = 0.032) as independent predictors of GIC. At 24 h, clinical improvement was more frequent in patients with GIC (80 vs. 49%, p = 0.01). Conclusions: CTP CBF < 30% may overestimate infarct core volume, especially in patients imaged in the very early time window and with fast complete reperfusion. Therefore, the CTP CBF technique may exclude patients who would benefit from endovascular treatment.

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— Time to reperfusion is fundamental in reducing morbidity and mortality in acute stroke. We aimed to demonstrate that direct transfer to angio-suite (DTAS) of patients with suspected large vessel occlusion stroke improves workflow times and outcomes. Methods— A case-control matched study of the first 79 DTAS patients with confirmed large vessel occlusion (cases) and 145 no-DTAS patients (controls). DTAS protocol included a cone beam computed tomography in the angio-suite to rule out intracerebral hemorrhage for those patients with no prior neuroimaging in a referring center. Cases and controls were matched by location of vessel occlusion, age, baseline National Institutes of Health Stroke Scale (NIHSS) score and time from symptoms onset to Comprehensive Stroke Center arrival. Dramatic clinical improvement was defined as a decrease in NIHSS score of >10 points or final NIHSS score of ≤2. Favorable outcome was defined as modified Rankin Scale score of ≤2 at 90 days. Results— During an 18 months period a total of 97 patients were directly transferred to the angio-suite after admission: 11 (11.6%) showed an intracerebral hemorrhage on cone beam computed tomography, 7 (7.2%) did not have a large vessel occlusion on initial angiogram, and 79 (76.3%) had a large vessel occlusion and received endovascular treatment (cases). There were no differences in age, baseline NIHSS score, level of occlusion and time from onset-to-door between cases and controls. The median door-to-groin time (16 [12–20] versus 70 [45–105] minutes; P <0.01) and onset-to-groin times (222 [152–282] versus 259 [190–345] minutes; P <0.01) were shorter in the DTAS group. At 24 hours, DTAS patients presented lower NIHSS score (7 [4–16] versus 14 [4–20]; P =0.01), higher rate of dramatic improvement (50.6% Vs. 31.7%; P =0.04), and higher rate of favorable clinical outcome at 90 days (41% versus 28%; P =0.05). A logistic regression model adjusting for all matching variables showed that DTAS protocol was independently associated with 3 months favorable outcome (odds ratio, 2.5; 95% CI, 1.2–5.3; P =0.01). Conclusions— DTAS is an effective strategy to reduce workflow time which may significantly increase the odds of achieving a favorable outcome.

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.

201 patients were included: 87 DTER (43.3%), 74 DTCT (36.8%), 40 DTAS (19.9%).Ten DTAS patients (25%) did not receive EVT: 3 (7.5%) showed intracranial hemorrhage on cone-beam CT and 7 (17.5%) did not show an occlusion on angiography. Mean door-to-puncture (D2P) time was shorter in DTAS (17±8 min) than DTCT (60±29 min; p<0.01). D2P was longer in DTER (90±53 min) than in the other protocols (p<0.01). For outcome analyses only patients who received EVT were compared; no significant differences in baseline characteristics, including time from symptom-onset to admission, puncture-to-recanalization, or recanalization rate, were seen. However, time from symptom-to-puncture (DTAS: 197±72 min, DTER: 279±156, DTCT: 224±142 min; p=0.01) and symptom-to-recanalization (DTAS: 257±74, DTER: 355±158, DTCT: 279±146 min; p<0.01) were longer in the DTER group. At 24 hours, there were no differences in NIHSS score (p=0.81); however, the rate of dramatic clinical improvement was significantly higher in DTAS: 48.6% (DTER 24.1%, DTCT 27.4%); p=0.01). An adjusted model pointed to shorter onset-to-puncture time as an independent predictor of dramatic improvement (OR=1.23, 95% CI 1.13 to 133; p<0.01) CONCLUSION: In a subgroup of patients direct transfer and triage in the angiosuite seems feasible, safe, and achieves significant reduction in hospital workflow times.

Background and Purpose— Substantial proportion of patients who achieve successful recanalization of acute ischemic stroke due to large vessel occlusion do not achieve good functional outcome. We aim to analyze the effect of number of thrombectomy device passes and degree of the recanalization (by modified Thrombolysis in Cerebral Infarction) on the clinical and functional outcome. Methods— Five hundred forty-two consecutive patients underwent mechanical thrombectomy for large vessel occlusion in the anterior circulation at a single tertiary stroke center. Baseline characteristics, number of passes, recanalization degree, clinical outcome at 24 hours (measured by National Institutes of Health Scale score), and functional outcome (measured by modified Rankin Scale at 90 days) were registered. Multivariate analysis was performed to determine the association of number of passes and degree of recanalization with dramatical clinical recovery (final National Institutes of Health Scale score ≤2 or decrease in 8 or more National Institutes of Health Scale score points in 24 hours) and good functional outcome (modified Rankin Scale score ≤2 at 90 days). Results— Four hundred fifty-nine patients (84%) achieved successful recanalization (modified Thrombolysis in Cerebral Infarction 2B–3), 213 (39%) of them after first device pass. In the multivariate analysis, first-pass recanalization and modified Thrombolysis in Cerebral Infarction 3 were independent predictors of good functional outcome (odds ratio, 2.5; 95% CI, 1.4–4.5; P =0.002 and odds ratio, 2.6 CI; 1.5–4.7; P =0.001, respectively) and dramatical clinical recovery (odds ratio, 1.8; 95% CI, 1.1–3; P =0.032 and odds ratio, 2.9; 95% CI, 1.7–5.1; P <0.001, respectively). Rate of recanalization declined after each pass 39% (213/542), 35% (113/310), 33% (63/190), and 24% (26/154) for passes 1 to 4, respectively and 28% (45/158) for every attempt above 4 passes ( P <0.001). In patients who achieved recanalization, a linear association between number of passes and good functional outcome was observed: 1 pass (58.6%), 2 passes (50.5%), 3 passes (48.4%), 4 passes (38.5%), or 5 or more passes (25.6%; P <0.001) as compared with patients who did not achieve recanalization (16.9%). Conclusions— High number of device passes and less degree of recanalization are associated with worse outcome in patients with acute ischemic stroke secondary to large vessel occlusion. Future studies should investigate the optimal number of passes that should be attempted in patients without substantial recanalization.