Characterizing Fast and Slow Progressors in Anterior Circulation Large Vessel Occlusion Strokes.

BACKGROUND AND PURPOSE: Infarct growth rate (IGR) in acute ischemic stroke is highly variable. We sought to evaluate impact of symptom-reperfusion time on outcomes in patients undergoing mechanical thrombectomy (MT). METHODS: A prospectively maintained database from January,2012-August,2020 was reviewed. All patients with isolated MCA-M1 occlusion who achieved complete reperfusion(mTICI2C-3), had a witnessed symptom onset and follow-up MRI were included. IGR was calculated as final infarct volume (FIV)(ml)/symptom onset to reperfusion time(hours) and was dichotomized according to the median value into slow-(SP) versus fast-progressors (FP). The primary analysis aimed to evaluate the impact of symptom-reperfusion time on 90-day mRS in SP and FP. Secondary analysis was performed to identify predictors of IGR. RESULTS: A total of 137 patients were eligible for analysis. Mean age was 63 ± 15.4 years and median IGR was 5.13ml/hour. SP(n = 69) had higher median ASPECTS, lower median rCBF<30% lesion volume, higher proportion of favorable collaterals and hypoperfusion intensity ratio (HIR)<0.4, higher minimal mean arterial blood pressure before reperfusion, and lower rates of general anesthesia compared to FP(n = 68). Symptom-reperfusion time was comparable between both groups. SP had higher rates of 90-day mRS0-2(71.9%vs.38.9%,aOR;7.226,95%CI[2.431-21.482],p < 0.001) and lower median FIV. Symptom-reperfusion time was associated with 90-day mRS0-2 in FP (aOR;0.541,95%CI[0.309-0.946],p = 0.03) but not in SP (aOR;0.874,95%CI[0.742-1.056],p = 0.16). On multivariable analysis, high ASPECTS and favorable collaterals in the NCCT/CTA model, and low rCBF<30% and HIR<0.4 in the CTP model were independent predictors of SP. CONCLUSIONS: The impact of symptom-reperfusion time on outcomes significantly varies across slow-versus fast-progressors. ASPECTS, collateral score, rCBF<30%, and HIR define stroke progression profile.

No Racial Disparity in Outcome Measures After Endovascular Treatment for Stroke in the Elderly.

BACKGROUND AND PURPOSE: Despite the lower rates of good outcomes and higher mortality in elderly patients, age does not modify the treatment effect of mechanical thrombectomy for large vessel occlusion strokes. We aimed to study whether racial background influences the outcome after mechanical thrombectomy in the elderly population. METHODS: We reviewed a prospectively maintained database of patients with acute ischemic stroke treated with mechanical thrombectomy from October 2010 through June 2020 to identify all consecutive patients with age ≥80 years and anterior circulation large vessel occlusion strokes. The patients were categorized according to their race as Black and White. Univariable and multivariable analyses were performed to define the predictors of 90-day modified Rankin Scale and mortality in the overall population and in each race separately. RESULTS: Among 2241 mechanical thrombectomy, a total of 344 patients (median [interquartile range]; age 85 [82-88] years, baseline National Institutes of Health Stroke Scale score of 19 [15-23], Alberta Stroke Program Early CT Score 9 [7-9], 69.5% females) were eligible for the analysis. White patients (n=251; 73%) had significantly lower median body mass index (25.37 versus 26.89, P=0.04) and less frequent hypertension (78.9% versus 90.3%, P=0.01) but more atrial fibrillation (64.5% versus 44.1%, P=0.001) compared with African Americans (n=93; 27%). Other clinical, imaging, and procedural characteristics were comparable between groups. The rates of symptomatic intracerebral hemorrhage, 90-day modified Rankin Scale score of 0 to 2, and mortality were comparable among both groups. On multivariable analysis, race was neither a predictor of 90-day modified Rankin Scale score of 0 to 2 (White race: odds ratio, 0.899 [95% CI, 0.409-1.974], P=0.79) nor 90-day mortality (White race: odds ratio, 1.368; [95% CI, 0.715-2.618], P=0.34). CONCLUSIONS: In elderly patients undergoing mechanical thrombectomy for acute ischemic stroke, there was no racial difference in terms of outcome.

Lack of Reperfusion Rather Than Number of Passes Defines Futility in Stroke Thrombectomy: A Matched Case-Control Study.

Background and Purpose: There is a robust relationship between the duration of ischemia and functional outcomes after mechanical thrombectomy. Higher number of mechanical thrombectomy passes strongly correlate with lower chances of favorable outcomes. Indeed, previous studies have suggested that after multiple passes the procedure may be futile. However, using uncontrolled thresholds to define thrombectomy futility might be misleading. We aim to compare the outcome of successful reperfusion after 4 to 5 passes and ≥6 passes with those of failed reperfusion. Methods: A prospectively acquired mechanical thrombectomy database from January 2012 to October 2019 was reviewed. Patients were included if they had intracranial internal carotid artery or middle cerebral artery-M1/M2 occlusions and either achieved successful reperfusion after ≥4 passes or failed reperfusion. Reperfused patients (mTICI2b-3) were divided into 2 subgroups; (1) 4 to 5 passes and (2) ≥6 passes. Each subgroup was compared with a matched group of mechanical thrombectomy failure (mTICI0-2a). The primary outcome was the shift in the degree of disability at 90-day as measured by the modified Rankin Scale. Results: A total of 273 patients were included. As compared with matched failed reperfusion patients (n=62), those reperfused after 4 to 5 passes (n=62) had a favorable shift in the overall modified Rankin Scale score distribution (adjusted odds ratio, 3.992 [95% CI, 1.807­8.512], P=0.001] and higher rates of functional independence (31% versus 8.9%, P=0.004, adjusted odds ratio; 9.860 [95% CI, 2.323­41.845], P=0.002) at 90 days. Similarly, when compared with a matched group of failed reperfusion (n=42), patients reperfused after ≥6 passes (n=42) demonstrated a favorable shift in the overall modified Rankin Scale score distribution (adjusted odds ratio, 2.640 [95% CI, 1.073­6.686], P=0.037) and had higher rates of functional independence (36.8% vs 11.1%, P=0.004, adjusted odds ratio, 5.392 [95% CI, 1.185­24.530], P=0.029) at 90 day. Rates of parenchymal hematoma type-2 and 90-day mortality were comparable in the reperfused and nonreperfused groups. Conclusions: Achieving reperfusion despite multiple passes leads to improved outcomes compared with failed procedures. Arbitrary uncontrolled thresholds for a maximum number of passes to predict futile recanalization may lead to inappropriate early termination of procedures.

Baseline Characteristics of Patients with Symptomatic Carotid Webs: A Matched Case Control Study.

BACKGROUND AND PURPOSE: The baseline characteristics of patients with symptomatic carotid web (CaW) are unclear. We investigate demographic and cerebrovascular risk factors in patients with this overlooked stroke etiology. METHODS: We identified consecutive patients diagnosed with symptomatic CaW at a comprehensive stroke center from July 2014-December 2018. These patients were matched at a 1:4 ratio (based on age and NIHSS scores) to create a control group of acute ischemic stroke (AIS) patients with non-CaW etiologies from the local GetWithTheGuidelines stroke database. RESULTS: Thirty patients with symptomatic CaW were compared to 120 AIS patients with non-CaW etiologies. Symptomatic CaW patients were more likely to be female (73.3 vs. 44.2%; p = 0.004) and black (86.7 vs. 64.2%; p = 0.02). Symptomatic CaWs patients had a fewer absolute number of modifiable cerebrovascular risk factors (1.7±1.1 vs. 2.5±1.2; p = 0.002), lower rates of hypertension (43.4 vs. 63.3%; p = 0.04), and a more favorable lipid profile with lower average LDL (89.5±30.3 vs. 111.2±43.7 mg/dL; p = 0.01) and higher average HDL (47.9±11.3 vs. 42.2±13.8 mg/dL; p = 0.01) as compared to strokes with non-CaW etiology. Symptomatic CaW patients were more likely to have a large vessel occlusion (80.0 vs. 51.7%; p = 0.005), despite similar e-ASPECTS between the groups (8.1±2.1 vs. 8.3±2.2; p = 0.30). On multivariable analysis, symptomatic CaW was an independent predictor of independence at discharge (OR 3.72; 95%CI 1.27-10.94). CONCLUSION: A gender and racial predilection of symptomatic CaWs may exist as females and blacks were were found to be more likely affected. Symptomatic CaW patients have a more benign cerebrovascular risk factor profile corroborating the proposed mechanism of local stasis and thromboembolism. Despite presenting more commonly with LVO, symptomatic CaW was associated with good functional outcome, warranting further studies.

Reliability of Field Assessment Stroke Triage for Emergency Destination Scale Use by Paramedics: Mobile Stroke Unit First-Year Experience.

Background and Purpose: Field Assessment Stroke Triage for Emergency Destination (FAST-ED) scale is a helpful tool to triage patients with stroke in the field. However, data on its reliability in the prehospital setting are lacking. We aim to test the reliability of FAST-ED scale when used by paramedics in a mobile stroke unit covering a metropolitan area. Methods: As part of standard operating mobile stroke unit procedures, paramedics initially evaluated patients. If the event characterized a stroke alert, the FAST-ED score was determined by the paramedic upon patient contact (in-person) and then independently by a vascular neurologist (VN) immediately after paramedic evaluation (remotely/telemedicine). This allowed testing of the interrater agreement of the FAST-ED scoring performance between on-site prehospital providers and remotely located VN. Results: Of a total of 238 patients transported in the first 15 months of the mobile stroke unit's activity, 173 were included in this study. Median age was 63 (interquartile range, 55.5­75) years and 52.6% were females. A final diagnosis of ischemic stroke was made in 71 (41%), transient ischemic attack in 26 (15%), intracranial hemorrhage in 15 (9%), whereas 61 (35%) patients were stroke mimics. The FAST-ED scores matched perfectly among paramedics and VN in 97 (56%) instances, while there was 0 to 1-point difference in 158 (91.3%), 0 to 2-point difference in 171 (98.8%), and 3 or more point difference in 2 (1.1%) patients. The intraclass correlation between VN and paramedic FAST-ED scores showed excellent reliability, intraclass correlation coefficient 0.94 (95% CI, 0.92­0.96; P<0.001). When VN recorded FAST-ED score ≥3, paramedics also scored FAST-ED≥3 in majority of instances (63/71 patients; 87.5%). A large vessel occlusion was identified in 16 (9.2%) patients; 13 occlusions were identified with a FAST-ED≥3 while 3 were missed. All of the latter patients had National Institutes of Health Stroke Scale score ≤5. Conclusions: We demonstrate excellent reliability of FAST-ED scale performed by paramedics when compared with VN, indicating that it can be accurately performed by paramedics in the prehospital setting.

Baseline ASPECTS and hypoperfusion intensity ratio influence the impact of first pass reperfusion on functional outcomes.

BACKGROUND: First pass reperfusion (FPR) has been established as a key performance metric in mechanical thrombectomy (MT). The impact of FPR may be more relevant in fast progressors. We aim to study the impact of baseline Alberta Stroke Program Early CT Score (ASPECTS) on non-contrast CT and hypoperfusion intensity ratio (HIR) on CT perfusion on clinical outcomes after FPR. METHODS: A prospective MT database was reviewed for patients with isolated occlusion of the intracranial internal carotid artery and/or middle cerebral artery M1 segment who underwent MT with complete reperfusion (modified Thrombolyis in Cerebral Infarction score 2c-3) from January 2012 to May 2019. The overall population was divided into ASPECTS >7 versus ≤7 and the subgroup of patients with baseline CT perfusion was divided into HIR <0.3 versus ≥0.3. Univariable and multivariable analyses were performed to establish the predictors of 90-day functional independence (modified Rankin Scale (mRS) ≤2) in each subgroup. RESULTS: A total of 436 patients were included in the analyses. FPR was achieved in 254 (58.3%) patients. ASPECTS modified the effect of FPR on clinical outcomes, with FPR predicting good outcomes in patients with ASPECTS ≤7 (46% vs 29%, adjusted OR 3.748; 95% CI 1.590 to 8.838, p=0.003) while no significant effect was detected in those with ASPECTS >7 (62.3% vs 53.1%, adjusted OR 1.372; 95% CI 0.798 to 2.358, p=0.25). Similarly, FPR predicted good outcomes in patients with HIR ≥0.3 (54.8% vs 41.9%, adjusted OR 2.204; 95% CI 1.148 to 4.233, p=0.01) but not in those with HIR <0.3 (62.9% vs 52.8%, adjusted OR 1.524; 95% CI 0.592 to 3.920, p=0.38). CONCLUSIONS: The impact of FPR on functional outcomes is highly dependent on baseline imaging characteristics, with a more prominent influence in patients presenting with lower ASPECTS and/or higher HIR.

Body Mass Index and Clinical Outcomes in Large Vessel Occlusion Acute Ischemic Stroke after Endovascular Therapy.

BACKGROUND AND PURPOSE: Several reports have described lower mortality rates in overweight or obese patients as compared to normal weight ones. In the past decade, several studies have investigated the phenomenon, commonly known as the obesity paradox, with mixed results thus far. We sought to determine whether outcomes differ between patients with large vessel occlusion strokes (LVOS) after endovascular therapy (ET) according to their body mass index (BMI). METHODS: We reviewed our prospectively collected endovascular database at a tertiary care academic institution. All patients that underwent ET for acute LVOS were categorized according to their BMI into 4 groups: (1) underweight (BMI < 18.5), (2) normal weight (BMI = 18.5-25), (3) overweight (BMI = 25-30), and (4) obese (BMI > 30). Baseline characteristics, procedural radiological as well as outcome parameters where compared. RESULTS: A total of 926 patients qualified for the study, of which 20 (2.2%) were underweight, 253 (27.3%) had a normal weight, 315 (34%) were overweight, and 338 (36.5%) were obese. When compared with normal weight (reference), overweight patients were younger, had higher rates of dyslipidemia and diabetes and higher glucose levels, while obese patients were younger, less often smokers, and had higher rates of hypertension and diabetes and higher glucose levels. Other baseline and procedural characteristics were comparable. The rates of successful reperfusion (modified treatment in cerebral ischemia, 2b-3), parenchymal hematomas, 90-day good clinical outcomes (modified Rankin scale, 0-2), and 90-day mortality were comparable between groups. On multivariate analysis, BMI was not associated with good outcomes nor mortality. CONCLUSION: In patients treated with mechanical thrombectomy, BMI is not associated with outcomes. However, patients who are overweight or obese have more comorbidities and a higher stroke risk and, thus, should strive for a normal weight.

Acute Neurological Deterioration in Large Vessel Occlusions and Mild Symptoms Managed Medically.

Background and Purpose- It is unclear which factors predict acute neurological deterioration in patients with large vessel occlusion and mild symptoms. We aim to evaluate the frequency, timing, and potential predictors of acute neurological deterioration ≥4 National Institutes of Health Stroke Scale (NIHSS) points in medically managed patients with large vessel occlusion and mild presentation. Methods- Single-center retrospective study of patients with consecutive minor stroke (defined as NIHSS score of ≤5 on presentation) and large vessel occlusion from January 2014 to December 2017. Primary outcome was acute neurological deterioration ≥4 NIHSS points during the hospitalization. Secondary outcomes included ΔNIHSS (defined as discharge minus admission NIHSS score). Results- Among 1133 patients with acute minor strokes, 122 (10.6%) had visible occlusions on computed tomography angiography/magnetic resonance angiography. Twenty-four (19.7%) patients had ≥4 points deterioration on NIHSS at a median of 3.6 (1-16) hours from arrival. No clinical or radiological predictors of acute neurological deterioration ≥4 NIHSS points were observed on multivariable analysis. Rescue endovascular thrombectomy was performed more often in the ones with acute neurological deterioration ≥4 NIHSS points compared with patients with no deterioration (54% versus 0%; P<0.001). Acute neurological deterioration ≥4 NIHSS points was associated with ΔNIHSS ≥4 points (33% versus 4.9%; P<0.01) and a trend toward lower independence rates at discharge (50% versus 70%; P=0.06) compared with the group with no deterioration. In patients with any degree of neurological worsening, patients who underwent rescue thrombectomy were more likely to be independent at discharge (73% versus 38%; P=0.02) and to have a favorable ΔNIHSS (-2 [-3 to 0] versus 0 [-1 to 6]; P=0.05) compared with the ones not offered rescue thrombectomy. Conclusions- Acute neurological deterioration ≥4 NIHSS points was observed in a fifth of patients with large vessel occlusion and mild symptoms, occurred very early in the hospital course, impacted functional outcomes, and could not be predicted by any of the studied clinical and radiological variables. Rescue thrombectomy was associated with improved clinical outcomes at discharge in patients with neurological deterioration.

Markers of coagulation and hemostatic activation aid in identifying causes of cryptogenic stroke.

OBJECTIVE: To test the hypothesis that markers of coagulation and hemostatic activation (MOCHA) help identify causes of cryptogenic stroke, we obtained serum measurements on 132 patients and followed them up to identify causes of stroke. METHODS: Consecutive patients with cryptogenic stroke who met embolic stroke of undetermined source (ESUS) criteria from January 1, 2017, to October 31, 2018, underwent outpatient cardiac monitoring and the MOCHA profile (serum D-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, and fibrin monomer) obtained ≥2 weeks after the index stroke; abnormal MOCHA profile was defined as ≥2 elevated markers. Prespecified endpoints monitored during routine clinical visits included new atrial fibrillation (AF), malignancy, venous thromboembolism (VTE), or other defined hypercoagulable states (HS). RESULTS: Overall, 132 patients with ESUS (mean age 64 ± 15 years, 61% female, 51% nonwhite) met study criteria. During a median follow-up of 10 (interquartile range 7-14) months, AF, malignancy, VTE, or HS was identified in 31 (23%) patients; the 53 (40%) patients with ESUS with abnormal MOCHA were significantly more likely than patients with normal levels to have subsequent new diagnoses of malignancy (21% vs 0%, p < 0.001), VTE (9% vs 0%, p = 0.009), or HS (11% vs 0%, p = 0.004) but not AF (8% vs 9%, p = 0.79). The combination of 4 normal MOCHA and normal left atrial size (n = 30) had 100% sensitivity for ruling out the prespecified endpoints. CONCLUSION: The MOCHA profile identified patients with cryptogenic stroke more likely to have new malignancy, VTE, or HS during short-term follow-up and may be useful in direct evaluation for underlying causes of cryptogenic stroke.

A Pilot Study Validating Video-Based Training on Pre-Hospital Stroke Recognition.

INTRODUCTION: Delays in recognizing stroke during pre-hospital emergency medical system (EMS) care may affect triage and transport time to an appropriate stroke ready hospital and may preclude patients from receiving time dependent treatment. All EMS transports in a large urban area in the stroke belt were evaluated for transport destinations, triage and transport time and stroke recognition following distribution ofan educational training video to local EMS services. HYPOTHESIS: Following video training, local paramedics will improve stroke recognition and shorten triage and transport time to appropriate stroke centers of care. METHODS: A training module (<10 min) containing a stroke triage scenario, instruction on the Cincinnati Prehospital Stroke Score (CPSS) and the Los Angeles Prehospital Stroke Score (LAPSS) and 'where to transport' stroke patients was distributed and viewed by 96 paramedics. Data was collected from February to October 2016. Stroke recognition was determined from one primary stroke center (PSC) hospital's confirmation of EMS delivered patients (Site A). Yearly stroke recognition percentages of 44% from Site A in 2014 were used as baseline. RESULTS: A total of 34,833 emergency 911 response transports were made with a total of 502 (1.4%) suspected strokes identified by paramedics. Median [IQR] triage and transport time for stroke transports was 33 [27-41] min. The PSC hospitals received a 5% increase in stroke transports and non-specific care facilities decreased by 7%. From 8,554 transports to site A (PSC) confirmed strokes totalled 107 transports with 139 suspected strokes by paramedics. Of these transports, 60 were correctly identified by paramedics (positive predictive value of 43%, sensitivity of 56%). By the second month following training, recognition percentages increased from baseline to 64%. At five months, percentages of correct stroke identification had dropped to 36%. CONCLUSION: Video based training improved stroke recognition by an additional 19%, but continual monthly or quarterly training is recommended for maintenance of increased stroke recognition.

Longer stent retrievers enhance thrombectomy performance in acute stroke.

BACKGROUND: Longer stent retrievers have recently become available and have theoretical advantages over their shorter counterparts. We aim to evaluate whether stent retriever length impacts reperfusion rates in stroke thrombectomy. METHODS: This was a retrospective analysis of a prospectively collected thrombectomy database in which equal diameter (4 mm) stent retrievers were used as the first-line strategy for intracranial internal carotid or middle cerebral artery M1 or M2 occlusions along with a balloon guide catheter from June 2011 to March 2017. The population was dichotomized into long (Trevo 4×30 mm/Solitaire 4×40 mm) or short (Trevo 4×20 mm/Solitaire 4×20 mm) retrievers. The primary outcome was first-pass modified Thrombolysis in Cerebral Infarction (mTICI) 2b/3 reperfusion. RESULTS: Of 1126 thrombectomies performed within the study period, 420 were included. Age, gender, National Institutes of Health Stroke Scale, ASPECTS, IV tissue plasminogen activator use, stroke etiology, occlusion site, time from last-known-normal to puncture, distribution of Trevo and Solitaire, and the use of newer generation local thromboaspiration devices were comparable between the long and short retrievers. The short retriever group had more frequent hypertension, dyslipidemia, and atrial fibrillation. First-pass mTICI 2b/3 reperfusion was more common in the long retriever group (62% vs 50%; P=0.01). Parenchymal hematomas type 2, subarachnoid hemorrhage, 90-day modified Rankin Scale score 0-2, and mortality were comparable. Multivariable analysis indicated that long retriever (OR 2.2; 95% CI 1.3 to 3.6; P=0.001), radiopaque device (OR 2.1; 95% CI 1.2 to 3.4; P=0.003), and adjuvant local aspiration (OR 2.4; 95% CI 1.3 to 4.3; P=0.003) were independently associated with first-pass reperfusion. CONCLUSIONS: The use of longer stent retrievers is an independent predictor of first-pass mTICI 2b/3 reperfusion. First-pass reperfusion was also associated with the use of radiopaque devices and adjuvant local aspiration.

Coagulation markers and echocardiography predict atrial fibrillation, malignancy or recurrent stroke after cryptogenic stroke.

We evaluated the utility of left atrial volume index (LAVI) and markers of coagulation and hemostatic activation (MOCHA) in cryptogenic stroke (CS) patients to identify those more likely to have subsequent diagnosis of atrial fibrillation (AF), malignancy or recurrent stroke during follow-up.Consecutive CS patients who met embolic stroke of undetermined source (ESUS) who underwent transthoracic echocardiography and outpatient cardiac monitoring following stroke were identified from the Emory cardiac registry. In a subset of consecutive patients, d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex and fibrin monomer (MOCHA panel) were obtained ≥2 weeks post-stroke and repeated ≥4 weeks later if abnormal; abnormal MOCHA panel was defined as ≥2 elevated markers which did not normalize when repeated. We assessed the predictive abilities of LAVI and the MOCHA panel to identify patients with subsequent diagnosis of AF, malignancy, recurrent stroke or the composite outcome during follow-up.Of 94 CS patients (mean age 64 ± 15 years, 54% female, 63% non-white, mean follow-up 1.4 ± 0.8 years) who underwent prolonged cardiac monitoring, 15 (16%) had new AF. Severe LA enlargement (vs normal) was associated with AF (P < .06). In 42 CS patients with MOCHA panel testing (mean follow-up 1.1 ± 0.6 years), 14 (33%) had the composite outcome and all had abnormal MOCHA. ROC analysis showed LAVI and abnormal MOCHA together outperformed either test alone with good predictive ability for the composite outcome (AUC 0.84).We report the novel use of the MOCHA panel in CS patients to identify a subgroup of patients more likely to have occult AF, occult malignancy or recurrent stroke during follow-up. A normal MOCHA panel identified a subgroup of CS patients at low risk for recurrent stroke on antiplatelet therapy. Further study is warranted to evaluate whether the combination of an elevated LAVI and abnormal MOCHA panel identifies a subgroup of CS patients who may benefit from early anticoagulation for secondary stroke prevention.

Automated CT Perfusion Prediction of Large Vessel Acute Stroke from Intracranial Atherosclerotic Disease.

BACKGROUND AND PURPOSE: We have observed that large vessel occlusion acute strokes (LVOS) due to intracranial atherosclerotic disease (ICAD) present with more benign CT perfusion (CTP) profiles, which we presume to potentially represent enhanced collateralization compared to embolic LVOS. We aim to determine if CTP profiles can predict ICAD in LVOS. METHODS: Retrospective review of a prospectively collected interventional stroke database from September 2010 to March 2015. Patients with intracranial ICA/MCA-M1/M2 occlusions and CTP were dichotomized into ICAD versus non-ICAD etiologies. Ischemic core (relative cerebral blood flow < 30%) and hypoperfusion volumes were estimated by automated CTP. RESULTS: A total of 250 patients met the inclusion criteria, comprised of 21 (8%) ICAD and 229 non-ICAD etiologies. Baseline characteristics were similar between groups, except for higher HbA1c levels (p < 0.01), LDL cholesterol (p < 0.01), systolic blood pressure (p < 0.01), and lower rate of atrial fibrillation (p < 0.01) in ICAD patients. There were no significant differences in volumes of baseline ischemic core (p = 0.54) among groups. ICAD patients had smaller Tmax > 4 s, Tmax > 6 s, and Tmax > 10 s absolute lesions, and a higher ratio of Tmax > 4 s/Tmax > 6 s volumes (median 2 [1.6-2.3] vs. 1.6 [1.4-2.0]; p = 0.02). A Tmax > 4 s/Tmax > 6 s ratio ≥2 showed specificity = 73%/sensitivity = 52% for ICAD and was observed in 47.6% of ICAD versus 26.1% of non-ICAD patients (p = 0.07). Clinical outcomes were comparable amongst groups. Multivariate logistic regression revealed that Tmax > 4 s/Tmax > 6 s ratio ≥2 (OR 3.75, 95% CI 1.05-13.14, p = 0.04), higher LDL cholesterol (OR 1.1, 95% CI 1.01-1.03, p = 0.01), and higher systolic pressure (OR 1.03, 95% CI 1.01-1.04, p = 0.01) were independently associated with ICAD. CONCLUSION: An automated CTP Tmax > 4 s/Tmax > 6 s ratio ≥2 profile was found independently associated with underlying ICAD LVOS.

Endovascular Therapy and Ethnic Disparities in Stroke Outcomes.

BACKGROUND AND PURPOSE: Ethnic disparities in stroke are well described, with a higher incidence of disability and increased mortality in Blacks versus Whites. We sought to compare the clinical outcomes between those ethnic groups after stroke endovascular therapy (ET). METHODS: We performed a retrospective review of the prospectively acquired Grady Endovascular Stroke Outcomes Registry between September 1, 2010 and September 30, 2015. Patients were dichotomized into two groups - Caucasians and African-Americans - and matched for age, pretreatment glucose level, and baseline National Institutes of Health Stroke Scale (NIHSS) score. Baseline characteristics as well as procedural and outcome parameters were compared. RESULTS: Out of the 830 patients treated with ET, 308 pairs of patients (n = 616) underwent primary analysis. African-Americans were younger (p < 0.01), had a higher prevalence of hypertension (p < 0.01) and diabetes (p = 0.04), and had higher Alberta Stroke Program Early CT Score values (p = 0.03) and shorter times to treatment (p = 0.01). Blacks more frequently had Medicaid coverage and less private insurance (29.6 vs. 11.4% and 41.5 vs. 60.3%, respectively, p < 0.01). The remaining baseline characteristics, including baseline NIHSS score and CT perfusion-derived ischemic core volumes, were well balanced. There were no differences in the overall distribution of 90-day modified Rankin scale scores (p = 0.28), rates of successful reperfusion (84.7 vs. 85.7%, p = 0.91), good outcomes (49.1 vs. 44%, p = 0.24), or parenchymal hematomas (6.5 vs. 6.8%, p = 1.00). Blacks had lower 90-day mortality rates (18 vs. 24.6%, p = 0.04) in univariate analysis, which persisted as a nonsignificant trend after adjustment for potential confounders (OR 0.52, 95% CI 0.26-1.03, p = 0.06). CONCLUSIONS: Despite unique baseline characteristics, African-Americans treated with ET for large vessel occlusion strokes have similar outcomes as Caucasians. Greater availability of ET may diminish the ethnic/racial disparities in stroke outcomes.

Clinical and Imaging Outcomes of Endovascular Therapy in Patients with Acute Large Vessel Occlusion Stroke and Mild Clinical Symptoms.

BACKGROUND: The minimal stroke severity justifying endovascular intervention remains elusive. However, a significant proportion of patients presenting with large vessel occlusion stroke (LVOS) and mild symptoms go untreated and face poor outcomes. We aimed to evaluate the clinical outcomes of patients presenting with LVOS and low symptom scores (National Institutes of Health Stroke Scale [NIHSS] score ≤8) undergoing endovascular therapy (ET). METHODS: We performed a retrospective analysis of a prospectively collected ET database between September 2010 and March 2016. Endovascularly treated patients with LVOS and a baseline NIHSS score ≤8 were included. Baseline patient characteristics, procedural details, and outcome parameters were collected. Efficacy outcomes were the rate of good outcome (90-day modified Rankin Scale score 0-2) and of successful reperfusion (modified Treatment in Cerebral Infarction [mTICI] score 2b-3). Safety was assessed by the rate of parenchymal hematoma (parenchymal hematoma type 1 [PH-1] and parenchymal hematoma type 2 [PH-2]) and 90-day mortality. Logistic regression was used to identify predictors of good clinical outcomes. RESULTS: A total of 935 patients were considered; 72 patients with an NIHSS score ≤8 were included. Median [IQR] age was 61.5 years [56.2-73.0]; 39 patients (54%) were men. Mean (SD) baseline NIHSS score, computed tomography perfusion core volume, and ASPECTS were 6.3 (1.5), 7.5 mL (16.1), and 8.5 (1.3), respectively. Twenty-eight patients (39%) received intravenous tissue plasminogen activator. Occlusions locations were as follows: 29 (40%) proximal MCA-M1, 20 (28%) MCA-M2, 6 (8%) ICA terminus, and 9 (13%) vertebrobasilar. Tandem occlusion was documented in 7 patients (10%). Sixty-seven patients (93%) achieved successful reperfusion (mTICI score 2b-3); 52 (72%) had good 90-day outcomes. Mean final infarct volume was 32.2 ± 59.9 mL. Parenchymal hematoma occurred in 4 patients (6%). Ninety-day mortality was 10% (n = 7). Logistic regression showed that only successful reperfusion (OR 27.7, 95% CI 1.1-655.5, p = 0.04) was an independent predictor of good outcomes. CONCLUSION: Our findings demonstrate that ET is safe and feasible for LVOS patients presenting with mild clinical syndromes. Future controlled studies are warranted.

Carotid Web (Intimal Fibromuscular Dysplasia) Has High Stroke Recurrence Risk and Is Amenable to Stenting.

BACKGROUND AND PURPOSE: Carotid webs have been increasingly recognized as a cause of recurrent stroke, but evidence remains scarce. We aim to report the clinical outcomes and first series of carotid stenting in a cohort of patients with strokes from symptomatic carotid webs. METHODS: Prospective and consecutive data of patients <65 years old with cryptogenic stroke admitted within September 2014 to May 2017. Carotid web was defined by a shelf-like/linear filling defect in the posterior internal carotid artery bulb by computed tomographic angiography. RESULTS: Twenty-four patients were identified (91.6% strokes/8.4% transient ischemic attacks [TIAs]). Median age was 46 (41-59) years, 61% were female, and 75% were black. Median National Institutes of Health Stroke Scale score was 10.5 (3.0-16.0) and ASPECTS (Alberta Stroke Program Early CT Score) was 8 (7-8). There were no parenchymal hemorrhages, and 96% of patients were independent at 3 months. All webs caused <50% stenosis. In patients with bilateral webs (58%), median ipsilateral web length was larger than contralateral (3.1 [3.0-4.5] mm versus 2.6 [1.85-2.9] mm; P=0.01), respectively. Twenty-nine percent of patients had thrombus superimposed on the symptomatic carotid web. A recurrent stroke/TIA involving the territory of the previously symptomatic web occurred in 7 (32%; 6 strokes/1 TIA) patients: 3 <1 week, 2 1 year of follow-up. Two recurrences occurred on dual antiplatelet therapy, 3 on antiplatelet monotherapy, 1 within 24 hours of thrombolysis, and 1 off antithrombotics. Median follow-up was 12.2 (8.0-18.0) months. Sixteen (66%) patients were stented at a median 12.2 (7.0-18.7) days after stroke with no periprocedural complications. No recurrent strokes/TIAs occurred in stented individuals (median follow-up of 4 [2.4-12.0] months). CONCLUSIONS: Carotid web is associated with high recurrent stroke/TIA risk, despite antithrombotic use, and is amenable to carotid stenting.

Computed Tomographic Perfusion Selection and Clinical Outcomes After Endovascular Therapy in Large Vessel Occlusion Stroke.

BACKGROUND AND PURPOSE: Different imaging paradigms have been used to select patients for endovascular therapy in stroke. We sought to determine whether computed tomographic perfusion (CTP) selection improves endovascular therapy outcomes compared with noncontrast computed tomography alone. METHODS: Review of a prospectively collected registry of anterior circulation stroke patients undergoing stent-retriever thrombectomy at a tertiary care center between September 2010 and March 2016. Patients undergoing CTP were compared with those with noncontrast computed tomography alone. The primary outcome was the shift in the 90-day modified Rankin scale (mRS). RESULTS: A total of 602 patients were included. CTP-selected patients (n=365, 61%) were younger (P=0.02) and had fewer comorbidities. CTP selection (n=365, 61%) was associated with a favorable 90-day mRS shift (adjusted odds ratio [aOR]=1.49; 95% confidence interval [CI], 1.06-2.09; P=0.02), higher rates of good outcomes (90-day mRS score 0-2: 52.9% versus 40.4%; P=0.005), modified Thrombolysis in Cerebral Infarction-3 reperfusion (54.8% versus 40.1%; P<0.001), smaller final infarct volumes (24.7 mL [9.8-63.1 mL] versus 34.6 mL [13.1-88 mL]; P=0.017), and lower mortality (16.6% versus 26.8%; P=0.005). When matched on age, National Institutes of Health Stroke Scale (NIHSS) score, and glucose (n=424), CTP remained associated with a favorable 90-day mRS shift (P=0.016), lower mortality (P=0.02), and higher rates of reperfusion (P<0.001). CTP better predicted functional outcomes in patients presenting after 6 hours (as assessed by comparison of logistic regression models: Akaike information criterion: 199.35 versus 287.49 and Bayesian information criterion: 196.71 versus 283.27) and those with an Alberta Stroke Program Early Computed Tomography Score ≤7 (Akaike information criterion: 216.69 versus 334.96 and Bayesian information criterion: 213.6 versus 329.94). CONCLUSIONS: CTP selection is associated with a favorable mRS shift in patients undergoing stent-retriever thrombectomy. Future prospective studies are warranted.

Too good to intervene? Thrombectomy for large vessel occlusion strokes with minimal symptoms: an intention-to-treat analysis.

INTRODUCTION: The minimal stroke severity justifying endovascular intervention remains elusive; however, a significant proportion of patients presenting with large vessel occlusion (LVO) and mild symptoms subsequently decline and face poor outcomes. OBJECTIVE: To evaluate our experience with these patients by comparing best medical therapy with thrombectomy in an intention-to-treat analysis. METHODS: Analysis of prospectively collected data of all consecutive patients with National Institutes of Health Stroke Scale (NIHSS) score ≤5, LVO on CT angiography, and baseline modified Rankin Scale (mRS) score 0-2 from November 2014 to May 2016. After careful discussion with patients/family, a decision to pursue medical or interventional therapy was made. Deterioration (development of aphasia, neglect, and/or significant weakness) triggered reconsideration of thrombectomy. The primary outcome measure was NIHSS shift (discharge NIHSS score minus admission NIHSS score). RESULTS: Of the 32 patients qualifying for the study, 22 (69%) were primarily treated with medical therapy and 10 (31%) intervention. Baseline characteristics were comparable. Nine (41%) medically treated patients had subsequent deterioration requiring thrombectomy. Median time from arrival to deterioration was 5.2 hours (2.0-25.0). Successful reperfusion (modified Treatment in Cerebral Infarction 2b-3) was achieved in all 19 thrombectomy patients. The NIHSS shift significantly favored thrombectomy (-2.5 vs 0; p<0.01). The median NIHSS score at discharge was low with both thrombectomy (1 (0-3)) and medical therapy (2 (0.5-4.5)). 90-Day mRS 0-2 rates were 100% and 77%, respectively (p=0.15). Multivariable linear regression indicated that thrombectomy was independently associated with a beneficial NIHSS shift (unstandardized ß -4.2 (95% CI -8.2 to -0.1); p=0.04). CONCLUSIONS: Thrombectomy led to a shift towards a lower NIHSS in patients with LVO presenting with minimal stroke symptoms. Despite the overall perception that this condition is benign, nearly a quarter of patients primarily treated with medical therapy did not achieve independence at 90 days.

Emergency transport of stroke suspects in a rural state: opportunities for improvement.

INTRODUCTION: Time delay is the key obstacle for receiving successful stroke treatment. Alteplase therapy must start within 4.5 hours from stroke occurrence. Rapid transport to a primary stroke center (PSC) or acute stroke-ready hospital (ASRH) by the emergency medical system (EMS) paramedics is vital. We determined transport time and destination data for EMS-identified and -delivered stroke suspects in Arkansas during 2013. Our objective was to analyze transport time and the hospital qualification for stroke care across the state. METHODS: The state's 75 counties were placed into 8 geographical regions (R1-R8). Transport time and hospital qualification were determined for all EMS-identified strokes. Each hospital's stroke care status was categorized as PSC, ASRH, a nonspecialty or unknown care facility (NSCF), out-of-state, or nonapplicable designation facilities. RESULTS: There were 9588 EMS stroke ground transports with median within-region transport times of 29-40 minutes. Statewide, only 65% of EMS-transported stroke patients were transported to either PSC (12%) or ASRH (53%) facilities. One-third of the patients (30.6%) were delivered to NSCFs, where acute stroke therapy may rarely be performed. Regions with the highest suspected-stroke cases per capita also had the highest percentage of transports to NSCFs. CONCLUSION: With only a few PSCs in Arkansas, EMS agencies should prioritize transporting stroke patients to ASRHs when PSCs are not regionally located.

Predictors of major improvement after intravenous thrombolysis in acute ischemic stroke.

BACKGROUND: Intravenous thrombolysis improves outcomes of stroke patients. The immediate response to thrombolysis is variable and few studies attempted to identify predictors of major neurological improvement (MNI) 24 h following thrombolysis. Our objective is to determine predictors of MNI 24 h following thrombolysis. METHODS: We reviewed the prospective database of patients treated through our telestroke network and at our institution between November 2008 and June 2012. We included all patients who received IV t-PA and had a 24-h NIHSS score available. Similar to previous studies, we defined MNI as a reduction in NIHSS score by ≥8 points, or a score of 0 or 1 at 24 h. Demographics, risk factors, time to treatment, and clinical and laboratory data, were compared between MNI present or absent. Baseline predictors were compared using t- and Fisher's exact tests, and outcomes using multivariate logistic regression analysis. RESULTS: Out of 316 patients, 306 had 24-h NIHSS scores and 38% of them experienced MNI. Patients with MNI were less likely to be older than 80 years (16% vs. 29%, p = 0.008) and to have atrial fibrillation (9% vs. 24%, p = 0.001) compared to those without; we found no other predictors of MNI. After adjusting for baseline demographics and risk factors, age less than 80 years (OR = 1.9, 95% CI 1.1-3.6) and absence of atrial fibrillation (OR = 3.0, 95% CI: 1.4-6.2) predicted MNI. CONCLUSION: Major neurological improvement within 24 h after thrombolysis is more likely in younger patients and those without atrial fibrillation.