Recommendations on angiographic revascularization grading standards for acute ischemic stroke: a consensus statement

Value of Thrombus CT Characteristics in Patients with Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Thrombus CT characteristics might be useful for patient selection for intra-arterial treatment. Our objective was to study the association of thrombus CT characteristics with outcome and treatment effect in patients with acute ischemic stroke.

MATERIALS AND METHODS

We included 199 patients for whom thin-section NCCT and CTA within 30 minutes from each other were available in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute ischemic stroke in the Netherlands (MR CLEAN) study. We assessed the following thrombus characteristics: location, distance from ICA terminus to thrombus, length, volume, absolute and relative density on NCCT, and perviousness. Associations of thrombus characteristics with outcome were estimated with univariable and multivariable ordinal logistic regression as an OR for a shift toward better outcome on the mRS. Interaction terms were used to investigate treatment-effect modification by thrombus characteristics.

RESULTS

In univariate analysis, only the distance from the ICA terminus to the thrombus, length of >8 mm, and perviousness were associated with functional outcome. Relative thrombus density on CTA was independently associated with functional outcome with an adjusted common OR of 1.21 per 10% (95% CI, 1.02-1.43; P = .029). There was no treatment-effect modification by any of the thrombus CT characteristics.

CONCLUSIONS

In our study on patients with large-vessel occlusion of the anterior circulation, CT thrombus characteristics appear useful for predicting functional outcome. However, in our study cohort, the effect of intra-arterial treatment was independent of the thrombus CT characteristics. Therefore, no arguments were provided to select patients for intra-arterial treatment using thrombus CT characteristics.

Comparison of multimodal intra-arterial treatment versus intravenous thrombolysis for hypertensive patients with severe large vessel cerebral infarction

Since intravenous thrombolysis (IVT) is often associated with poor outcomes in hypertensive patients with severe acute cerebral infarction (ACI) due to occlusions of the internal carotid, basilar, or proximal middle cerebral artery, we evaluated whether multimodal intra-arterial treatment (IAT) might improve functional outcomes in this patient population. We retrospectively reviewed the charts of eligible patients who underwent multimodal IAT including intra-arterial thrombolysis, mechanical thrombectomy, balloon and/or stent angioplasty (IAT group) or IVT alone (IVT group). Outcomes included the revascularization rate 24 hours postprocedure, the frequency of survival at 7, 90, and 180 days postonset, and a measure of functional outcomes using the modified Rankin Scale (mRS). The IAT group included 62 patients and the IVT group included 31 patients. Multimodal IAT increased the revascularization rate at 24 hours (p<0.001) and the frequency of survival and functional independence (mRS ≤2) at 7 days (p<0.001 and p=0.018, respectively), 90 days (both p<0.001), and 180 days (both p<0.001). Independent predictors of longer survival were treatment with multimodal IAT (HR 0.1; 95% CI 0.0 to 0.4; p<0.001) and revascularization (HR 0.1; 95% CI 0.0 to 0.4; p<0.001), whereas a longer duration from onset to treatment was a risk factor for death (HR 1.4; 95% CI 1.2 to 1.8; p<0.001). There was no significant between-group difference for symptomatic hemorrhagic transformation. This study found that for patients with severe hypertensive ACI with large vessel occlusions, multimodal IAT improved the outcomes, including early revascularization, survival, and functional outcome.

Comparisons of ASPECTS 5 and 6 for endovascular treatment in anterior circulation occlusive stroke

Background Whether ASPECTS 5 and ASPECTS 6 were significantly different on clinical outcomes in acute anterior circulation ischemic stroke undergoing endovascular treatment remains unclear. We aimed to retrospectively compare the effectiveness and safety of ASPECTS 5 and ASPECTS 6 in acute anterior circulation large-artery occlusive stroke patients. Methods A total of 41 patients, 14 in the ASPECTS 5 group and 27 in the ASPECTS 6 group, were enrolled between January 2014 and June 2016. Modified Rankin Scale 0-2 was considered as good functional outcome. Symptomatic intracerebral hemorrhage at 72 hours and mortality at 90 days were recorded. Results Good functional outcome at 90 days in the ASPECTS 5 group (0% (0/14)) was significantly lower than that in the ASPECTS 6 group (25.9% (7/27)) ( p = 0.04). Rates of symptomatic intracranial hemorrhage (21.4 (3/14) vs 18.5% (5/27), p = 0.83) and mortality (64.3% (9/14) vs 44.4% (12/27), p = 0.23) within 90 days were not significantly different. There is a trend for a lower rate of successful reperfusion in the ASPECTS 5 group (71.4% (10/14) for ASPECTS 5 vs 92.6% (25/27) for ASPECTS 6, p = 0.07). Conclusions ASPECTS 5 has very little chance to reach good functional outcome in Chinese patients with anterior circulation large-artery occlusive stroke. Future studies with large sample sizes are needed.

Monitored Anesthesia Care vs Intubation for Vertebrobasilar Stroke Endovascular Therapy

Importance

No consensus regarding the ideal sedation treatment for stroke endovascular therapy has been reached, and practices remain largely based on local protocols and clinician preferences. Most studies have focused on anterior circulation strokes; therefore, little is known regarding the optimal anesthesia type for vertebrobasilar occlusion strokes.

Objective

To compare clinical and angiographic outcomes between monitored anesthesia care (MAC) and general anesthesia (GA) in patients presenting with vertebrobasilar occlusion strokes.

Design, Setting, and Participants

Retrospective, matched, case-control study of consecutive vertebrobasilar occlusion strokes treated with endovascular therapy at 2 academic institutions. The study took place between September 2005 and September 2015 at University of Pittsburgh Medical Center Stroke Institute, Pittsburgh, Pennsylvania, and between September 2010 and September 2015 at the Marcus Stroke and Neuroscience Center at Grady Memorial Hospital, Atlanta, Georgia. Patients requiring emergent intubation prior to endovascular therapy were excluded. The remaining patients were categorized into (1) MAC and (2) elective intubation for the procedure (elective GA). Patients who converted from MAC to GA during the procedure were included in the MAC group. The 2 groups were matched for age, baseline National Institutes of Health Stroke Scale score, and glucose levels. Baseline characteristics and outcomes were compared.

Main Outcomes and Measures

The primary outcome measure was the shift in the degree of disability among the 2 groups as measured by the modified Rankin scale at 90 days.

Results

A total of 215 patients underwent endovascular therapy for vertebrobasilar occlusion strokes during the study period. Thirty-nine patients were excluded owing to emergent pre-endovascular therapy intubation. Sixty-three patients had MAC (36%) and 113 patients had GA (64%). The conversion rate from MAC to GA was 13% (n = 8). After matching, 61 pairs of patients (n = 122) underwent primary analysis. The 2 groups were well balanced in terms of baseline characteristics. Median age was 69 years (interquartile range, 60-75 years) in the MAC group vs 67 years (interquartile range, 55.5-78.5 years) in the GA group (P = .83). Fifty-four percent of the patients in the MAC group were men vs 41% in the GA group (P = .44). When compared with the elective GA group, patients who underwent the procedure with MAC had similar rates of successful reperfusion, good clinical outcomes, hemorrhagic complications, and mortality. The modality of anesthesia was not associated with any significant changes in the modified Rankin scale score distribution (MAC: OR, 1.52; 95% CI, 0.80-2.90; P = .19).

Conclusions and Relevance

In endovascular therapy for acute posterior circulation stroke, MAC is feasible and appears to be as safe and effective as GA. Future clinical trials are warranted to confirm our findings.

Utility of digital subtraction angiography-based collateral evaluation in medically treated acute symptomatic basilar artery stenosis

BACKGROUND AND PURPOSE

Although a stroke from atherosclerosis in the basilar artery (BA) often presents with mild initial stroke severity, it has heterogeneous clinical courses. We investigated the efficacy of digital subtraction angiography (DSA)-based collateral perfusion evaluation in association with long-term outcomes of medically treated symptomatic basilar artery stenosis.

METHODS

From a registry database of all consecutive patients with stroke, we included 98 medically treated patients (due to mild initial stroke severity) [National Institute of Health Stroke Scale (NIHSS) scores ≤ 4; symptomatic basilar artery stenosis, 70-99%] with available initial diagnostic DSA. Basilar collateral scoring was performed via the DSA, using a modified version of the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology grading system in both the superior cerebellar artery and anterior/posterior-inferior cerebellar artery territories (score 0-8). The outcomes were designated as the 90-day modified Rankin Scale (mRS90) score (poor, 3-6). Student's t-test, chi-square test and logistic regression analyses were used to identify factors associated with a poor outcome.

RESULTS

The median initial NIHSS score was 2 [interquartile range (IQR), 0-3], median posterior circulation Alberta Stroke Program Early CT Score was 8 (IQR, 7-10), median collateral score was 7 (IQR, 7-8) and 20 (20.4%) had poor mRS90 scores. In multivariate analysis, poorer collateral scores (P = 0.003), higher NIHSS scores (P = 0.005) and lower posterior circulation Alberta Stroke Program Early CT Score (P = 0.017) were independently associated with a poor mRS90 score.

CONCLUSIONS

The DSA-based collateral scoring of the BA large branches might predict long-term outcome in medically treated symptomatic basilar artery stenosis with mild initial severity. Evaluation of BA collateral perfusion status might be useful to determine appropriate treatment strategies.

Baseline Blood Pressure Effect on the Benefit and Safety of Intra-Arterial Treatment in MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands)

Background and Purpose—

High blood pressure (BP) is associated with poor outcome and the occurrence of symptomatic intracranial hemorrhage in acute ischemic stroke. Whether BP influences the benefit or safety of intra-arterial treatment (IAT) is not known. We aimed to assess the relation of BP with functional outcome, occurrence of symptomatic intracranial hemorrhage and effect of IAT.

Methods—

This is a post hoc analysis of the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands). BP was measured at baseline, before IAT or stroke unit admission. We estimated the association of baseline BP with the score on the modified Rankin Scale at 90 days and safety parameters with ordinal and logistic regression analysis. Effect of BP on the effect of IAT was tested with multiplicative interaction terms.

Results—

Systolic BP (SBP) had the best correlation with functional outcome. This correlation was U-shaped; both low and high baseline SBP were associated with poor functional outcome. Higher SBP was associated with symptomatic intracranial hemorrhage (adjusted odds ratio, 1.25 for every 10 mm Hg higher SBP [95% confidence interval, 1.09–1.44]). Between SBP and IAT, there was no interaction for functional outcome, symptomatic intracranial hemorrhage, or other safety parameters; the absolute benefit of IAT was evident for the whole SBP range. The same was found for diastolic BP.

Conclusions—

BP does not affect the benefit or safety of IAT in patients with acute ischemic stroke caused by proximal intracranial vessel occlusion. Our data provide no arguments to withhold or delay IAT based on BP.

Clinical Trial Registration—

URL: http://www.isrctn.com . Unique identifier: ISRCTN10888758.

Two Paradigms for Endovascular Thrombectomy After Intravenous Thrombolysis for Acute Ischemic Stroke

Importance

Intravenous thrombolysis (IVT) followed by mechanical thrombectomy (MT) is recommended to treat acute ischemic stroke (AIS) with a large vessel occlusion (LVO). Most hospitals do not have on-site MT facilities, and most patients need to be transferred secondarily after IVT (drip and ship), which may have an effect on the neurologic outcome.

Objective

To compare the functional independence at 3 months between patients treated under the drip-and-ship paradigm and those treated on site (mothership).

Design, Setting, and Participants

This study used a prospectively gathered registry of patients with AIS to select patients admitted through the Saint-Antoine and Tenon (drip and ship) or the Fondation Rothschild (mothership) hospitals from January 1, 2013, through April 30, 2016. The study included patients older than 18 years treated with bridging therapy for AIS with LVO of the anterior circulation. Among the 159 patients who received MT at the mothership, 100 had been transferred after IVT from the drip-and-ship hospitals and 59 had received IVT on site.

Main Outcomes and Measures

The main outcome was 3-month functional independence (modified Rankin scale score ≤2). Both groups were compared using a multivariate linear model, including variables that were significantly different in the 2 groups.

Results

During the study period, 497 patients were hospitalized at the drip-and-ship and mothership hospitals for an AIS eligible to reperfusion therapy; 11 patients had a basilar artery occlusion and were excluded, leaving 100 patients in the drip-and-ship group (mean age, 73 years; age range, 60-81 years; 57 men [57.0%]) and 59 in the mothership group (mean age, 70 years; age range, 58-82 years; 29 men [49.2%]). The proportion of patients with a favorable neurologic outcome at 3 months was similar in both groups (drip and ship, 61 [61.0%]; mothership, 30 [50.8%]; P = .26), even after adjusting the analysis for the baseline National Institutes of Health Stroke Scale score, diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score, and general anesthesia (P = .82). Patients had less severe conditions in the drip-and-ship group (median baseline National Institutes of Health Stroke Scale score, 15 vs 17 [P = .03]; median diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score, 7.5 vs 7 [P = .05]). Process times were longer in the drip-and-ship group (onset-to-needle time, 150 vs 135 minutes; onset-to-puncture time, 248 vs 189 minutes; and onset-to-recanalization time, 297 vs 240 minutes; P < .001). Both groups were similar in terms of substantial recanalization (Thrombolysis in Cerebral Ischemia scores 2B to 3; drip and ship, 84 [84.0%]; mothership, 47 [79.7%]; P = .49) and symptomatic hemorrhagic transformation (drip and ship, 2 [2.0%]; mothership, 2 [3.4%]; P = .63).

Conclusions and Relevance

This study found that patients treated under the drip-and-ship paradigm also benefit from bridging therapy, with no statistically significant difference compared with those treated directly in a comprehensive stroke center.

Incomplete Large Vessel Occlusions in Mechanical Thrombectomy: An Independent Predictor of Favorable Outcome in Ischemic Stroke

BACKGROUND AND PURPOSE

Cerebral large vessel occlusion (LVO) in acute ischemic stroke (AIS) may be complete (CLVO) or incomplete (ILVO). The influence of ILVO on clinical outcome after mechanical thrombectomy (MT) remains unclear. We investigated primarily the clinical outcome in patients with AIS due to ILVO or CLVO.

METHODS

Five hundred three consecutive AIS patients with LVO treated with stent-retriever or direct aspiration-based MT between 2010 and 2016 were analyzed. The primary endpoint was favorable clinical outcome (modified Rankin Scale ≤2) at 90 days; secondary endpoints were periprocedural parameters.

RESULTS

Forty-nine patients (11.3%) with a median National Institutes of Health Stroke Scale (NIHSS) of 11 presented with ILVO and the remainder presented with CLVO and median NIHSS of 15 (p < 0.001). The median groin puncture-to-reperfusion time was 30 vs. 67 min, respectively (p < 0.001). Successful reperfusion was reached in 47 out of 49 ILVO (95.9%) vs. 298 out of 381 CLVO (78.2%; p < 0.005) with less retrieval maneuvers (1.7 ± 2.2 vs. 3.0 ± 2.5; p < 0.001). The favorable outcome at 90 days was 81% in patients with ILVO vs. 29.1% in CLVO (p < 0.001); respective all-cause mortality rates were 6.4 vs. 28.5% (p < 0.001). Periprocedural complications (6.9%) occurred exclusively in CLVO patients (p < 0.05). ILVO was associated with favorable clinical outcome independent of age and NIHSS in multivariate logistic regression both in the anterior (OR 3.6; 95% CI 1.8-6.9; p < 0.001) and posterior circulation (OR 3.5; 95% CI 1.8-6.9; p < 0.001).

CONCLUSIONS

AIS due to ILVO is frequent and is associated with a nearly threefold higher chance of favorable clinical outcome at 90 days, independent of age and initial NIHSS compared to CLVO.

The Impact of Conscious Sedation versus General Anesthesia for Stroke Thrombectomy on the Predictive Value of Collateral Status: A Post Hoc Analysis of the SIESTA Trial

BACKGROUND AND PURPOSE

Radiologic selection criteria to identify patients likely to benefit from endovascular stroke treatment are still controversial. In this post hoc analysis of the recent randomized Sedation versus Intubation for Endovascular Stroke TreAtment (SIESTA) trial, we aimed to investigate the impact of sedation mode (conscious sedation versus general anesthesia) on the predictive value of collateral status.

MATERIALS AND METHODS

Using imaging data from SIESTA, we assessed collateral status with the collateral score of Tan et al and graded it from absent to good collaterals (0-3). We examined the association of collateral status with 24-hour improvement of the NIHSS score, infarct volume, and mRS at 3 months according to the sedation regimen.

RESULTS

In a cohort of 104 patients, the NIHSS score improved significantly in patients with moderate or good collaterals (2-3) compared with patients with no or poor collaterals (0-1) (P = .011; mean, -5.8 ± 7.6 versus -1.1 ± 10.7). Tan 2-3 was also associated with significantly higher ASPECTS before endovascular stroke treatment (median, 9 versus 7; P < .001) and smaller mean infarct size after endovascular stroke treatment (median, 35.0 versus 107.4; P < .001). When we differentiated the population according to collateral status (0.1 versus 2.3), the sedation modes conscious sedation and general anesthesia were not associated with significant differences in the predictive value of collateral status regarding infarction size or functional outcome.

CONCLUSIONS

The sedation mode, conscious sedation or general anesthesia, did not influence the predictive value of collaterals in patients with large-vessel occlusion anterior circulation stroke undergoing thrombectomy in the SIESTA trial.

Ischemic Stroke Treatment Trials: Neuroimaging Advancements and Implications

There have been significant advancements in the treatment of acute ischemic stroke in the last 2 decades. Recent trials have placed a significant emphasis on minimizing the time from symptom onset to stroke treatment by reperfusion therapies, which decreases the cerebral infarct volume and improves clinical outcomes. These clinical advances have paralleled and been aided by advances in neuroimaging. However, controversy remains regarding how much time should be spent on neuroimaging evaluation versus expediting patient treatment. In this review article, we examine the key endovascular stroke trials published in the past 25 years, and we briefly highlight the failures and successes of endovascular stroke trials performed in the past 4 years. We also discuss the advantages and disadvantages of using time from symptom onset versus neuroimaging in determining endovascular stroke therapy candidacy.

Acute Basilar Artery Occlusion: Differences in Characteristics and Outcomes after Endovascular Therapy between Patients with and without Underlying Severe Atherosclerotic Stenosis

BACKGROUND AND PURPOSE

Prediction of underlying intracranial atherosclerotic stenosis before endovascular therapy might be helpful for appropriate therapeutic planning in patients with acute ischemic stroke. This study aimed to compare the characteristics and treatment outcomes in patients with acute basilar artery occlusion relative to the existence or nonexistence of underlying intracranial atherosclerotic stenosis.

MATERIALS AND METHODS

Sixty-two patients with acute basilar artery occlusion underwent multimodal endovascular therapy. All patients underwent stent-retriever thrombectomy as a first-line endovascular therapy. Patients with underlying intracranial atherosclerotic stenosis underwent additional intracranial angioplasty and stent placement. The clinical and imaging characteristics and treatment outcomes were retrospectively analyzed and compared between patients with and without intracranial atherosclerotic stenosis.

RESULTS

Underlying intracranial atherosclerotic stenosis was identified at the occlusion site in 15 patients (24.1%). Occlusion in the proximal segment of the basilar artery was more common in patients with intracranial atherosclerotic stenosis (60% versus 6.4%, P < .001), whereas occlusion in the distal segment was more common in those without it (91.5% versus 26.7%, P < .001). Bilateral thalamic infarction on a pretreatment DWI was less common in patients with intracranial atherosclerotic stenosis (0% versus 27.7%, P = .027) compared with those without it. There were no significant differences in the rates of successful revascularization, favorable outcome, symptomatic hemorrhage, and mortality between the 2 groups.

CONCLUSIONS

Underlying intracranial atherosclerotic stenosis was not uncommon in patients with acute basilar artery occlusion. The occlusion segment of the basilar artery and the presence or absence of bilateral thalamic infarction on a pretreatment DWI might be helpful for predicting underlying intracranial atherosclerotic stenosis in patients with acute basilar artery occlusion. Patients with and without underlying intracranial atherosclerotic stenosis who underwent endovascular therapy had similar outcomes.

Internal Carotid Artery and the Proximal M1 Segment Are Optimal Targets for Mechanical Thrombectomy

Background and Purpose

Mechanical thrombectomy (MT) is an established treatment of acute anterior circulation stroke caused by large vessel occlusion (LVO). We compared the clinical outcome (3-month modified Rankin Scale, mRS) in hyperacute (<3h from the onset of symptoms) ischemic stroke between an MT and an intravenous thrombolysis (IVT) cohort in proximal (ICA and the proximal M1 segment of the middle cerebral artery) and distal (the distal M1 and the M2 segment) LVOs.

Methods

We prospectively reviewed 67 patients who underwent MT with newer-generation stent retrievers. The IVT cohort consisted of 98 patients who received IVT without MT. We recorded baseline clinical, procedural and imaging variables, technical outcome, 24-h imaging outcome, and the clinical outcome. Differences between the groups were studied with theoretically appropriate statistical tests and binary logistic regression analysis.

Results

The proportion of patients who had a proximal LVO and experienced good (mRS ≤2) or excellent (mRS ≤1) clinical outcome was significantly larger in the MT group (62 vs. 7%, p < 0.001; 47 vs. 3%, p < 0.001, respectively). In a regression model including relevant confounding variables, good clinical outcome was seen significantly more often among patients with proximal occlusions (OR = 6.0, CI 95% 1.9-18.3, p = 0.002). In a similar model, no statistically significant differences were observed in patients with more distal occlusions.

Conclusions

MT is superior to IVT in achieving good clinical outcome in hyperacute anterior circulation stroke in the most proximal occlusions (ICA and proximal M1 segment). In the distal M1 and M2 segments neither of these therapies clearly outperforms the other.

Systolic Blood Pressure Within 24 Hours After Thrombectomy for Acute Ischemic Stroke Correlates With Outcome

Background

Current guidelines suggest treating blood pressure above 180/105 mm Hg during the first 24 hours in patients with acute ischemic stroke undergoing any form of recanalization therapy. Currently, no studies exist to guide blood pressure management in patients with stroke treated specifically with mechanical thrombectomy. We aimed to determine the association between blood pressure parameters within the first 24 hours after mechanical thrombectomy and patient outcomes.

Methods and Results

We retrospectively studied a consecutive sample of adult patients who underwent mechanical thrombectomy for acute ischemic stroke of the anterior cerebral circulation at 3 institutions from March 2015 to October 2016. We collected the values of maximum, minimum, and average values of systolic blood pressure, diastolic blood pressure, and mean arterial pressures in the first 24 hours after mechanical thrombectomy. Primary and secondary outcomes were patients’ functional status at 90 days measured on the modified Rankin scale and the incidence and severity of intracranial hemorrhages within 48 hours. Associations were explored using an ordered multivariable logistic regression analyses. A total of 228 patients were included (mean age 65.8±14.3; 104 males, 45.6%). Maximum systolic blood pressure independently correlated with a worse 90‐day modified Rankin scale and hemorrhagic complications within 48 hours (adjusted odds ratio=1.02 [1.01–1.03], P=0.004; 1.02 [1.01–1.04], P=0.002; respectively) in multivariable analyses, after adjusting for several possible confounders.

Conclusions

Higher peak values of systolic blood pressure independently correlated with worse 90‐day modified Rankin scale and a higher rate of hemorrhagic complications. Further prospective studies are warranted to identify whether systolic blood pressure is a therapeutic target to improve outcomes.

MRI quantitative T2* mapping on thrombus to predict recanalization after endovascular treatment for acute anterior ischemic stroke

BACKGROUND

In anterior acute ischemic stroke (AAIS) treated with endovascular treatment (EVT), the susceptibility vessel sign (SVS+ or SVS-) is related to recanalization results (TICI 2b/3) and clinical outcome. However, a binary qualitative assessment of thrombus using SVS does not reflect its complex composition. Our aim was to assess whether a quantitative MRI marker, Thrombus-T2* relaxation time, may be assessable in clinical routine and may to predict early successful recanalization after EVT, defined as a TICI 2b/3 recanalization obtained in 2 attempts or less.

MATERIAL AND METHODS

Thrombus-T2* relaxation time was prospectively obtained from consecutive AAIS patients treated by EVT (concomitant aspiration and stent retriever). Quantitative values were compared between early recanalization and late or unsuccessful recanalization.

RESULTS

Thirty patients with AAIS were included and Thrombus-T2* relaxation time was obtained in all patients. Earlier TICI 2b/3 recanalization were obtained in 22 patients (73%) and was significantly associated with SVS+ (1/8 vs. 16/22, P=0.01) and a shorter Thombus-T2* relaxation time (mean SD, range: 257, 18-50ms vs. 45 9, 35-60ms, P<0.001).

CONCLUSION

A new quantitative MRI biomarker, the Thrombus-T2* relaxation time is assessable in clinical routine. In a preliminary study of 30 patients, a shorter Thombus-T2* relaxation time is related to earlier recanalization after EVT using combination of stent retriever and aspiration.

Thrombectomy in Acute Ischemic Stroke: Challenges to Procedural Success

The overwhelming clinical benefit of intra-arterial stroke therapy owes to the major advance in revascularization brought on by the current generation of thrombectomy devices. Nevertheless, there remains a sizeable proportion of patients for whom substantial reperfusion cannot be achieved or is achieved too late. This article addresses the persistent challenges that face neurointerventionists and reviews technical refinements that may help to mitigate these obstacles to procedural success. Insights from in vitro modeling and clinical research are organized around a conceptual framework that examines the interaction between the device, the thrombus and the vessel wall.

Associations of Ischemic Lesion Volume With Functional Outcome in Patients With Acute Ischemic Stroke

Background and Purpose—

Ischemic lesion volume (ILV) on noncontrast computed tomography at 1 week can be used as a secondary outcome measure in patients with acute ischemic stroke. Twenty-four–hour ILV on noncontrast computed tomography has greater availability and potentially allows earlier estimation of functional outcome. We aimed to assess lesion growth 24 hours after stroke onset and compare the associations of 24-hour and 1-week ILV with functional outcome.

Methods—

We included 228 patients from MR CLEAN trial (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands), who received noncontrast computed tomography at 24-hour and 1-week follow-up on which ILV was measured. Relative and absolute lesion growth was determined. Logistic regression models were constructed either including the 24-hour or including the 1-week ILV. Ordinal and dichotomous (0–2 and 3–6) modified Rankin scale scores were, respectively, used as primary and secondary outcome measures.

Results—

Median ILV was 42 mL (interquartile range, 21–95 mL) and 64 mL (interquartile range: 30–120 mL) at 24 hours and 1 week, respectively. Relative lesion growth exceeding 30% occurred in 121 patients (53%) and absolute lesion growth exceeding 20 mL occurred in 83 patients (36%). Both the 24-hour and 1-week ILVs were similarly significantly associated with functional outcome (both P <0.001). In the logistic analyses, the areas under the curve of the receiver–operator characteristic curves were similar: 0.85 (95% confidence interval, 0.80–0.90) and 0.87 (95% confidence interval, 0.82–0.91) for including the 24-hour and 1-week ILV, respectively.

Conclusions—

Growth of ILV is common 24-hour poststroke onset. Nevertheless, the 24-hour ILV proved to be a valuable secondary outcome measure as it is equally strongly associated with functional outcome as the 1-week ILV.

Clinical Trial Registration—

URL: http://www.isrctn.com . Unique identifier: ISRCTN10888758.

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.

Preceding Intravenous Thrombolysis in Patients Receiving Endovascular Therapy

Background: The beneficial effects of endovascular therapy (EVT) in acute ischemic stroke have been demonstrated in recent clinical trials using new-generation thrombectomy devices. However, the comparative effectiveness and safety of preceding intravenous thrombolysis (IVT) in this population has rarely been evaluated. Methods: From a prospective multicenter stroke registry database in Korea, we identified patients with acute ischemic stroke who were treated with EVT within 8 h of onset and admitted to 14 participating centers during 2008-2013. The primary outcome was a modified Rankin Scale (mRS) score at 3 months. Major secondary outcomes were successful recanalization defined as a modified Treatment in Cerebral Ischemia score of 2b-3, functional independence (mRS score 0-2), mortality at 3 months, and symptomatic hemorrhagic transformation (SHT) during hospitalization. Multivariable logistic regression analyses using generalized linear mixed models were performed to estimate the adjusted odds ratios (ORs) of preceding IVT. Results: Of the 639 patients (male, 61%; age 69 ± 12; National Institutes of Health Stroke Scale score of 15 [11-19]) who met the eligibility criteria, 458 received preceding IVT. These patients showed lower mRS scores (adjusted common OR, 1.38 [95% CI 0.98-1.96]). Preceding IVT was associated with successful recanalization (1.96 [1.23-3.11]) and reduced 3-month mortality (0.58 [0.35-0.97]) but not with SHT (0.96 [0.48-1.93]). Conclusion: In patients treated with EVT within 8 of acute ischemic stroke onset, preceding IVT may enhance survival and successful recanalization without additional risk of SHT, and mitigate disability at 3 months.

Predictors of the Aspiration Component Success of a Direct Aspiration First Pass Technique (ADAPT) for the Endovascular Treatment of Stroke Reperfusion Strategy in Anterior Circulation Acute Stroke

BACKGROUND AND PURPOSE

A direct aspiration first pass technique (ADAPT) has been reported to be fast, safe, and effective for the treatment of acute ischemic stroke. The aim of this study is to determine the preoperative factors that affect success of the aspiration component of the technique in ischemic stroke patients with large vessel occlusion in the anterior circulation.

METHODS

We enrolled all 347 consecutive patients with anterior circulation acute ischemic stroke admitted for mechanical thrombectomy at our institution from August 2013 to October 2015 and treated by ADAPT for the endovascular treatment of stroke. Baseline and procedural characteristics, modified thrombolysis in cerebral infarction scores, and 3-month modified Rankin Scale were captured and analyzed.

RESULTS

Among the 347 patients (occlusion sites: middle cerebral artery=200, 58%; internal carotid artery Siphon=89, 25%; Tandem=58, 17%), aspiration component led to successful reperfusion (modified thrombolysis in cerebral infarction 2b/3 scores) in 55.6% (193/347 patients), stent retrievers were required in 40%, and a total successful final reperfusion rate of 83% (288/347) was achieved. Overall, procedural complications occurred in 13.3% of patients (48/347). Modified Rankin Scale score of 0 to 2 at 90 days was reported in 45% (144/323). Only 2 factors positively influenced the success of the aspiration component: an isolated middle cerebral artery occlusion (P<0.001) and a shorter time from stroke onset to clot contact (P=0.018).

CONCLUSIONS

In this large retrospective study, ADAPT was shown to be safe and effective for anterior circulation acute ischemic stroke with a final successful reperfusion achieved in 83%. The site of arterial occlusion and delay of the procedure were predictors for reperfusion.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02523261, NCT02678169, and NCT02466893.

Efficacy and Safety of Mechanical Thrombectomy in Older Adults with Acute Ischemic Stoke

OBJECTIVES

To evaluate the safety and efficacy of endovascular therapy in elderly adults treated for acute ischemic stroke.

DESIGN

Retrospective cohort study.

SETTING

Comprehensive Stroke Center, University of Tor Vergata, Rome, Italy.

PARTICIPANTS

Elderly adults treated for acute ischemic stroke (N = 219).

MEASUREMENTS

Participants were divided into two groups based on their age (n = 62, ≥80; n = 157, <80). Baseline and procedural characteristics, safety outcomes such as intracranial hemorrhage (ICH) and mortality and efficacy outcomes such as successful reperfusion and 3-month good clinical outcome of the two groups were compared. Mutivariable analysis was performed to identify predictors of clinical outcome.

RESULTS

Intravenous thrombolysis was more frequent (67.7% vs 52.8%, P = .04), and onset to reperfusion time was shorter (318.7 ± 128.7 vs 282 ± 53.5, P = .02) in participants aged 80 and older, but no between-group differences were found in terms of successful reperfusion (69% vs 63%, P = .4), good clinical outcome (30.6% vs 34.3%, P = .6), any (37% vs 37.5%, P > .99) or symptomatic (11% vs 14%, P = .6) ICH, or mortality (40.3% vs 29.2%, P = .14). Multivariable analysis revealed that, in the older group, onset National Institute of Health Stroke Scale (NIHSS) score (odds ratio (OR) = 0.65, 95% confidence interval (CI) = 0.44-0.96, P = .03) and 24-hour clinical improvement (OR = 141.13, 95% CI = 2.96-6,720.7, P = .01) were independent predictors of 3-month functional independence.

CONCLUSION

These findings suggest that endovascular treatment for stroke in selected elderly adults could be safe and effective. Major determinants of outcome in this subgroup of elderly patients are presentation NIHSS score and 24-hour clinical improvement.

Special Endovascular Treatment for Acute Large Artery Occlusion Resulting From Atherosclerotic Disease

BACKGROUND

Acute intracranial atherosclerotic disease (IAD)-related large artery occlusion (LAO) is typically refractory to mechanical thrombectomy. We evaluated the feasibility and safety of emergency balloon-assisted or stent-assisted angioplasty performed with tirofiban administration for acute IAD-related LAO.

METHODS

We identified, from among 55 consecutive patients who underwent endovascular treatment for LAO, 12 patients with acute IAD-related LAO who underwent balloon-assisted or stent-assisted angioplasty with (n = 3) or without passage of a stent retriever. The treatment included tirofiban administration. We obtained, from patients' clinical records, thrombolysis in cerebral infarction scores (to assess the extent of reperfusion), follow-up magnetic resonance angiography images (to assess patency of the responsive arteries), and 90-day modified Rankin (mRS) scores (to assess outcomes).

RESULTS

Temporary blood flow and severe stenosis were observed angiographically in all 12 patients, either when the stent retriever was deployed or when a microcatheter was advanced through the site of occlusion. Persistent recanalization was achieved in all patients, and there was no operative complication or arterial reocclusion. All 8 patients with an occluded major artery in the anterior circulation had a good outcome, with an mRS score of ≤2. Two of the 4 patients with basilar artery occlusion had a good outcome, with an mRS score of ≤2. One patient (25%) died within 72 hours after procedure.

CONCLUSIONS

Our data point to the safety and feasibility of emergency balloon-assisted or stent-assisted angioplasty performed with tirofiban administration and a single or no passage of the stent retriever for acute IAD-related LAO.

Transradial approach for mechanical thrombectomy in anterior circulation large-vessel occlusion

OBJECTIVE

The goals of this study were to describe the authors' recent institutional experience with the transradial approach to anterior circulation large-vessel occlusions (LVOs) in acute ischemic stroke patients and to report its technical feasibility.

METHODS

The authors reviewed their institutional database to identify patients who underwent mechanical thrombectomy via a transradial approach over the 2 previous years, encompassing their experience using modern techniques including stent retrievers.

RESULTS

Eleven patients were identified. In 8 (72%) of these patients the right radial artery was chosen as the primary access site. In the remaining patients, transfemoral access was initially attempted. Revascularization (modified Treatment in Cerebral Ischemia [mTICI] score ≥ 2b) was achieved in 10 (91%) of 11 cases. The average time to first pass with the stent retriever was 64 minutes. No access-related complications occurred.

CONCLUSIONS

Transradial access for mechanical thrombectomy in anterior circulation LVOs is safe and feasible. Further comparative studies are needed to determine criteria for selecting the transradial approach in this setting.

Endovascular stroke treatment in a small-volume stroke center

INTRODUCTION

Our purpose was to evaluate the safety and efficacy of endovascular treatment (EVT) of stroke caused by large vessel occlusions (LVO) performed by general interventional radiologists in cooperation with stroke neurologists and neuroradiologists at a center with a limited annual number of procedures. We aimed to compare our results with those previously reported from larger stroke centers.

PATIENTS AND METHODS

A total of 108 patients with acute stroke due to LVO treated with EVT were included. Outcome was measured using the modified Rankin scale (mRS) at 90 days. Efficacy was classified according to the modified thrombolysis in cerebral infarction (mTICI) scoring system. Safety was evaluated according to the incidence of procedural complications and symptomatic intracranial hemorrhage (sICH).

RESULTS

Mean age of the patients was 67.5 years. The median National Institutes of Health Stroke Scale (NIHSS) on hospital admission was 17. Successful revascularization was achieved in 76%. 39.4% experienced a good clinical outcome (mRS<3). Intraprocedural complications were seen in 7.4%. 7.4% suffered a sICH. 21.3% died within 3 months after EVT.

DISCUSSION

The use of general interventional radiologists in EVT of LVO may be a possible approach for improving EVT coverage where availability of specialized neurointerventionalists is challenging. EVT for LVO stroke performed by general interventional radiologists in close cooperation with diagnostic neuroradiologists and stroke neurologists can be safe and efficacious despite the low number of annual procedures.

ERic Acute StrokE Recanalization: A study using predictive analytics to assess a new device for mechanical thrombectomy

Aim and hypothesis Using a new study design, we investigate whether next-generation mechanical thrombectomy devices improve clinical outcomes in ischemic stroke patients. We hypothesize that this new methodology is superior to intravenous tissue plasminogen activator therapy alone. Methods and design ERic Acute StrokE Recanalization is an investigator-initiated prospective single-arm, multicenter, controlled, open label study to compare the safety and effectiveness of a new recanalization device and distal access catheter in acute ischemic stroke patients with symptoms attributable to acute ischemic stroke and vessel occlusion of the internal cerebral artery or middle cerebral artery. Study outcome The primary effectiveness endpoint is the volume of saved tissue. Volume of saved tissue is defined as difference of the actual infarct volume and the brain volume that is predicted to develop infarction by using an optimized high-level machine learning model that is trained on data from a historical cohort treated with IV tissue plasminogen activator. Sample size estimates Based on own preliminary data, 45 patients fulfilling all inclusion criteria need to complete the study to show an efficacy >38% with a power of 80% and a one-sided alpha error risk of 0.05 (based on a one sample t-test). Discussion ERic Acute StrokE Recanalization is the first prospective study in interventional stroke therapy to use predictive analytics as primary and secondary endpoint. Such trial design cannot replace randomized controlled trials with clinical endpoints. However, ERic Acute StrokE Recanalization could serve as an exemplary trial design for evaluating nonpivotal neurovascular interventions.

Vessel Patency at 24 Hours and Its Relationship With Clinical Outcomes and Infarct Volume in REVASCAT Trial (Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting Within Eight Hours of Symptom Onset)

BACKGROUND AND PURPOSE

Higher rates of target vessel patency at 24 hours were noted in the thrombectomy group compared with control group in recent randomized trials. As a prespecified secondary end point, we aimed to assess 24-hour revascularization rates by treatment groups and occlusion site as they related to clinical outcome and 24-hour infarct volume in REVASCAT (Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting Within Eight Hours of Symptom Onset).

METHODS

Independent core laboratory adjudicated vessel status according to modified arterial occlusive lesion classification at 24 hours on computed tomographic/magnetic resonance (94.2%/5.8%) angiography and 24-hour infarct volume on computed tomography were studied (95/103 patients in the thrombectomy group versus 94/103 in the control group, respectively). Complete revascularization was defined as modified arterial occlusive lesion grade 3. Its effect on clinical outcome was analyzed by ordinal logistic regression.

RESULTS

Complete revascularization was achieved in 70.5% of the solitaire group and in 22.3% of the control group (P<0.001). Significant differences in complete revascularization rates were found for terminus internal carotid artery, M1, and tandem occlusions (all P<0.001) but not for M2 occlusions. In the thrombectomy group, 2 out of 63 patients (3.1%) with modified Thrombolysis in Cerebral Infarction 2b/3 after thrombectomy showed arterial reocclusion (modified arterial occlusive lesion grade 0/1) at 24 hours. Complete revascularization was associated with improved outcome in both thrombectomy (adjusted odds ratio, 4.5; 95% confidence interval, 1.9-10.9) and control groups (adjusted odds ratio, 2.7; 95% confidence interval, 1.0-6.7). Revascularization (modified arterial occlusive lesion grade 2/3) was associated with smaller infarct volumes in either treatment arm.

CONCLUSIONS

Complete revascularization at 24 hours is a powerful predictor of favorable clinical outcome, whereas revascularization of any type results in reduced infarct volume in both thrombectomy and control groups.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01692379.

Early computed tomography-based scores to predict decompressive hemicraniectomy after endovascular therapy in acute ischemic stroke

Background

Identification of patients requiring decompressive hemicraniectomy (DH) after endovascular therapy (EVT) is crucial as clinical signs are not reliable and early DH has been shown to improve clinical outcome. The aim of our study was to identify imaging-based scores to predict the risk for space occupying ischemic stroke and DH.

Methods

Prospectively derived data from patients with acute large artery occlusion within the anterior circulation and EVT was analyzed in this monocentric study. Predictive value of non-contrast cranial computed tomography (ncCT) and cerebral blood volume (CBV) Alberta Stroke Program Early CT score (ASPECTS) were investigated for DH using logistic regression models and Receiver Operating Characteristic Curve analysis.

Results

From 218 patients with EVT, DH was performed in 20 patients (9.2%). Baseline- (7 vs. 9; p = 0.009) and follow-up ncCT ASPECTS (1 vs. 7, p<0.001) as well as baseline CBV ASPECTS (5 vs. 7, p<0.001) were significantly lower in patients with DH. ncCT (baseline: OR 0.71, p = 0.018; follow-up: OR 0.32, p = <0.001) and CBV ASPECTS (OR 0.63, p = 0.008) predicted DH. Cut-off ncCT-ASPECTS on baseline was 7-, ncCT-ASPECTS on follow-up was 4- and CBV ASPECTS on baseline was 5 points.

Conclusions

ASPECTS could be useful to early identify patients requiring DH after EVT for acute large vessel occlusion.

Cervical Carotid Pseudo-Occlusions and False Dissections

Background and Purpose—

Pseudo-occlusion (PO) of the cervical internal carotid artery (ICA) refers to an isolated occlusion of the intracranial ICA that appears as an extracranial ICA occlusion on computed tomography angiography (CTA) or digital subtraction angiography because of blockage of distal contrast penetration by a stagnant column of unopacified blood. We aim to better characterize this poorly recognized entity.

Methods—

Retrospective review of an endovascular database (2010–2015; n=898). Only patients with isolated intracranial ICA occlusions as confirmed by angiographic exploration were included. CTA and digital subtraction angiography images were categorized according to their apparent site of occlusion as (1) extracranial ICA PO or (2) discernible intracranial ICA occlusion.

Results—

Cervical ICA PO occurred in 21/46 (46%) patients on CTA (17 proximal cervical; 4 midcervical). Fifteen (71%) of these patients also had PO on digital subtraction angiography. A flame-shaped PO mimicking a carotid dissection was seen in 7 (33%) patients on CTA and in 6 (29%) patients on digital subtraction angiography. Patients with and without CTA PO had similar age (64.8±17.1 versus 60.2±15.7 years; P =0.35), sex (male, 47% versus 52%; P =1.00), and intravenous tissue-type plasminogen activator use (38% versus 40%; P =1.00). The rates of modified Treatment In Cerebral Ischemia 2b-3 reperfusion were 71.4% in the PO versus 100% in the non-PO cohorts ( P <0.01). The rates of parenchymal hematoma, 90-day modified Rankin Scale score 0–2, and 90-day mortality were 4.8% versus 8% ( P =0.66), 40% versus 66.7% ( P =0.12), and 25% versus 21% ( P =0.77) in PO versus non-PO patients, respectively. Multivariate analysis indicated that PO patients had lower chances of modified Treatment In Cerebral Ischemia 3 reperfusion (odds ratio 0.14; 95% confidence interval 0.02–0.70; P =0.01).

Conclusions—

Cervical ICA PO is a relatively common entity and may be associated with decreased reperfusion rates.

Review of Post Ischemic Stroke Imaging and Its Clinical Relevance

In this day and age, multiple imaging modalities are available to the stroke physician in the post-treatment phase.The practical challenge for physicians who treat stroke is to evaluate the pros and cons of each technique and select the best choice for the situation. The choice of imaging modality remains contentious at best and varies among different institutions and centres. This is no simple task an there are many factors to consider, including the differential diagnosis which need to be evaluated, the availability and reliability of the imaging technique and time and expertise required to perform and interpret the scanning. Other ancillary competing interest also come into play such as the financial cost of the modality, the requirement for patient monitoring during the imaging procedure and patient comfort. In an effort to clear some of the ambiguity surrounding this topic we present some of the current techniques in use and others, which are still in the realm of research and have not yet transitioned into clinical practice.

The effects of pharmaceutical thrombolysis and multi-modal therapy on patients with acute posterior circulation ischemic stroke: Results of a one center retrospective study

BACKGROUND

The treatment method for acute ischemic stroke is rapidly developing, and the effects of endovascular modalities, when used alone or in combination, needs to be studied. We aimed to identify the difference between pharmaceutical thrombolysis and multi-modal therapy (MMT) used in acute posterior circulation ischemic stroke (APCIS) patients and also to detect the predictors for successful recanalization and favorable outcomes.

METHODS

A retrospective analysis of patients with APCIS who received thrombolytic pharmaceuticals and MMT from 2011 to 2016 was performed at the stroke center. Demographic information, therapeutic methods and the results were recorded. Logistic regression model was constructed in variables to determine the predictors of outcome.

RESULTS

A total of 124 patients were included in this study, the mean age was 59.6 ± 9.5 years and the mean admission National Institutes of Health Stroke Scale (NIHSS) was 15.1 ± 6.6. Recanalization was achieved in 87 (70.2%) patients and favorable outcomes were observed in 65 (52.4%) patients. Patients treated with MMT demonstrated a higher recanalization rate, especially the use of stent placement and thrombectomy device, which were also related to the favorable outcome three months post-stroke. Logistic regression showed that stent placement and thrombectomy were the predictors of recanalization, and a favorable outcome was associated with coronary artery disease, MMT methods as well as recanalization.

CONCLUSION

MMT methods, especially stent placement and thrombectomy device may be the first recommended for patients with a delayed admission time, and it may have the advantage of better perfusion and neurological outcomes.

Distinctive patterns on CT angiography characterize acute internal carotid artery occlusion subtypes

Noninvasive computed tomography angiography (CTA) is widely used in acute ischemic stroke, even for diagnosing various internal carotid artery (ICA) occlusion sites, which often need cerebral digital subtraction angiography (DSA) confirmation. We evaluated whether clinical outcomes vary depending on the DSA-based occlusion sites and explored correlating features on baseline CTA that predict DSA-based occlusion site.We analyzed consecutive patients with acute ICA occlusion who underwent DSA and CTA. Occlusion site was classified into cervical, cavernous, petrous, and carotid terminus segments by DSA confirmation. Clinical and radiological features associated with poor outcome at 3 months (3-6 of modified Rankin scale) were analyzed. Baseline CTA findings were categorized according to carotid occlusive shape (stump, spearhead, and streak), presence of cervical calcification, Willisian occlusive patterns (T-type, L-type, and I-type), and status of leptomeningeal collaterals (LMC).We identified 49 patients with occlusions in the cervical (n = 17), cavernous (n = 22), and carotid terminus (n = 10) portions: initial NIH Stroke Scale (11.4 ± 4.2 vs 16.1 ± 3.7 vs 18.2 ± 5.1; P < 0.001), stroke volume (27.9 ± 29.6 vs 127.4 ± 112.6 vs 260.3 ± 151.8 mL; P < 0.001), and poor outcome (23.5 vs 77.3 vs 90.0%; P < 0.001). Cervical portion occlusion was characterized as rounded stump (82.4%) with calcification (52.9%) and fair LMC (94.1%); cavernous as spearhead occlusion (68.2%) with fair LMC (86.3%) and no calcification (95.5%); and terminus as streak-like occlusive pattern (60.0%) with poor LMC (60.0%), and no calcification (100%) on CTA.Our study indicates that acute ICA occlusion can be subtyped into cervical, cavernous, and terminus. Distinctive findings on initial CTA can help differentiate ICA-occlusion subtypes with specific characteristics.

Predictive Factors for Good Outcome and Mortality After Stent-Retriever Thrombectomy in Patients With Acute Anterior Circulation Stroke

Background and Purpose

Predictive factors associated with stent-retriever thrombectomy for patients with acute anterior circulation stroke remain to be elucidated. This study aimed to investigate clinical and procedural factors predictive of good outcome and mortality after stent-retriever thrombectomy in a large cohort of patients with acute anterior circulation stroke.

Methods

We analyzed clinical and procedural data in 335 patients with acute anterior circulation stroke treated with stent-retriever thrombectomy. A good outcome was defined as a modified Rankin Scale score of 0 to 2 at 3 months. The associations between clinical, imaging, and procedural factors and good outcome and mortality, respectively, were evaluated using logistic regression analysis.

Results

Using multivariate analysis, age (odds ratio [OR], 0.965; 95% confidence interval [CI], 0.944-0.986; P=0.001), successful revascularization (OR, 4.658; 95% CI, 2.240-9.689; P<0.001), parenchymal hemorrhage (OR, 0.150; 95% CI, 0.049-0.460; P=0.001), and baseline NIHSS score (OR, 0.908; 95% CI, 0.855-0.965; P=0.002) were independent predictors of good outcome. Independent predictors of mortality were age (OR, 1.043; 95% CI, 1.002-1.086; P=0.041), successful revascularization (OR, 0.171; 95% CI, 0.079-0.370; P<0.001), parenchymal hemorrhage (OR, 2.961; 95% CI, 1.059-8.276; P=0.038), and a history of previous stroke/TIA (OR, 3.124; 95% CI, 1.340-7.281; P=0.008).

Conclusions

Age, revascularization status, and parenchymal hemorrhage are independent predictors of both good outcome and mortality after stent retriever thrombectomy for acute anterior circulation stroke. In addition, NIHSS score on admission is independently associated with good outcome, whereas a history of previous stroke is independently associated with mortality.

Elevated mean platelet volume is associated with poor outcome after mechanical thrombectomy

Background

Elevated mean platelet volume (MPV), indicating higher platelet activity, could be a predictor of prognosis in patients with acute ischemic stroke receiving medical therapy.

Objective

To investigate the relationship between MPV and functional outcome in patients with acute anterior circulation stroke 3 months after undergoing mechanical thrombectomy (MT).

Methods

A total of 153 consecutive patients with acute stroke following MT, in two separate stroke centers, were enrolled between May 2013 and March 2016. MPV was measured on admission. Subjects were divided into two groups according to average MPV level. Univariate and multivariate analyses were performed. MPV was also incorporated into the Houston IA Therapy (HIAT) score, which was developed as a scoring system to predict poor prognosis, and the prediction capability was compared with the HIAT score alone.

Results

The average MPV was 10.4 fL. Patients with high MPV had a significantly lower rate of functional independence (28.9% vs 57.1%, p=0.000). After multivariable analysis, elevated MPV remained an independent predictor of unfavorable outcome (OR=3.93, 95% CI 1.73 to 8.94, p=0.001). When the MPV cut-off value was set at 10.4 fL using the receiver operating characteristic (ROC) analysis, MPV ≥10.4 fL predicted unfavorable outcome with 62.1% sensitivity and 66.7% specificity, respectively. Addition of MPV to the HIAT score did not improve predictive power compared with the HIAT score system alone by a comparison of the areas under the two ROC curves (0.70 vs 0.62, p=0.174).

Conclusions

Elevated MPV is an independent predictor of poor outcome in patients with acute anterior circulation stroke undergoing MT at 3 months.

Correlation of Acute M1 Middle Cerebral Artery Thrombus Location with Endovascular Treatment Success and Clinical Outcome

PURPOSE

The location of the arterial occlusion can help with prognostication and treatment triage of acute stroke patients. We aimed to determine the effects of M1 distance-to-thrombus on angiographic recanalization success rate and clinical outcome following endovascular treatment of acute M1 occlusion.

METHODS

All acute ischemic stroke patients with M1 segment middle cerebral artery (MCA) occlusion on admission CT angiography (CTA) who underwent endovascular treatment were analyzed. The distance between thrombus origin and internal carotid artery (ICA) bifurcation was measured on admission CTA. The modified thrombolysis in cerebral infarction (mTICI) grades 2b (>50% of distal branch filling) and 3 (complete) were considered as successful recanalization. Favorable outcome was defined by 3-month follow-up modified Rankin scale (mRs) score ≤2.

RESULTS

Successful recanalization was achieved in 24 (71%) of 34 consecutive patients included in this study. The M1 distance-to-thrombus was shorter among patients with successful recanalization (5.4 ± 5.4 mm) versus those without (11.3 ± 7.6 mm, p = 0.015). The successful recanalization rate was higher among patients with M1 distance-to-thrombus ≤6 mm (odds ratio: 8, 95% confidence interval: 1.37-46.81, p = 0.023) compared with those with distance-to-thrombus >6 mm. There was no significant correlation between M1 distance-to-thrombus and 3-month mRs (rho: 0.131, p = 0.461); however, the distance-to-thrombus negatively correlated with admission National Institutes of Health Stroke Scale (NIHSS) scores (rho: -0.350, p=0.043). On the other hand, successful recanalization and admission NIHSS score were the only independent predictors of favorable outcome.

CONCLUSION

Shorter distance of M1 thrombus from ICA bifurcation is associated with higher rate of successful recanalization following endovascular treatment.

Effects of Workflow Optimization in Endovascularly Treated Stroke Patients - A Pre-Post Effectiveness Study

Endovascular treatment of acute ischemic stroke has become standard of care for patients with large artery occlusion. Early restoration of blood flow is crucial for a good clinical outcome. We introduced an interdisciplinary standard operating procedure (SOP) between neuroradiologists, neurologists and anesthesiologists in order to streamline patient management. This study analyzes the effect of optimized workflow on periprocedural timings and its potential influence on clinical outcome. Data were extracted from a prospectively maintained university hospital stroke database. The standard operating procedure was established in February 2014. Of the 368 acute stroke patients undergoing endovascular treatment between 2008 and 2015, 278 patients were treated prior to and 90 after process optimization. Outcome measures were periprocedural time intervals and residual functional impairment. After implementation of the SOP, time from symptom onset to reperfusion was significantly reduced (median 264 min prior and 211 min after SOP-introduction (IQR 228–32 min and 161–278 min, respectively); P<0.001). Especially faster supply of imaging and prompt transfer of patients to the angiography suite contributed to this effect. Time between hospital admission and groin puncture was reduced by half after process optimization (median 64 min after versus 121 min prior to SOP-introduction (IQR 54–77 min and 96–161 min, respectively); P<0.001). Clinical outcome was significantly better after workflow optimization as measured with the modified Rankin Scale (common odds ratio (OR) 0.56; 95% CI 0.32–0.98; P = 0.038). Optimization of workflow and interdisciplinary teamwork significantly improved the outcome of patients with acute ischemic stroke due to a significant reduction of in-hospital examination, transportation, imaging and treatment times.

Mechanical thrombectomy for basilar artery thrombosis: a comparison of outcomes with anterior circulation occlusions

Background and purpose

The benefits of mechanical thrombectomy (MT) in basilar artery occlusions (BAO) have not been explored in recent clinical trials. We compared outcomes and procedural complications of MT in BAO with anterior circulation occlusions.

Methods

Data from the Madrid Stroke Network multicenter prospective registry were analyzed, including baseline characteristics, procedure times, procedural complications, symptomatic intracranial hemorrhage (SICH), modified Rankin Scale (mRS), and mortality at 3 months.

Results

Of 479 patients treated with MT, 52 (11%) had BAO. The onset to reperfusion time lapse was longer in patients with BAO (median (IQR) 385 min (320–540) vs 315 min (240–415), p<0.001), as was the duration of the procedures (100 min (40–130) vs 60 min (39–90), p=0.006). Moreover, the recanalization rate was lower (75% vs 84%, p=0.01). A trend toward more procedural complications was observed in patients with BAO (32% vs 21%, p=0.075). The frequency of SICH was 2% vs 5% (p=0.25). At 3 months, patients with BAO had a lower rate of independence (mRS 0–2) (40% vs 58%, p=0.016) and higher mortality (33% vs 12%, p<0.001). The rate of futile recanalization was 50% in BAO versus 35% in anterior circulation occlusions (p=0.05). Age and duration of the procedure were significant predictors of futile recanalization in BAO.

Conclusions

MT is more laborious and shows more procedural complications in BAO than in anterior circulation strokes. The likelihood of futile recanalization is higher in BAO and is associated with greater age and longer procedure duration. A refinement of endovascular procedures for BAO might help optimize the results.

Catch Plus thrombectomy device in acute stroke: initial evaluation

OBJECTIVE

To report our initial experience with the Catch Plus thrombectomy device (CPD) in patients with acute ischemic stroke (AIS).

MATERIALS AND METHODS

We retrospectively evaluated the procedural variables as well as the clinical and angiographic outcomes of patients with acute occlusion of a major intracranial artery in the anterior circulation who were treated with CPD at our center. Baseline characteristics (gender, age, comorbidities, cardiovascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score, and vessel occlusion sites) of these patients were recorded. Thrombolysis in Cerebral Infarction (TICI) score, incidence of symptomatic and asymptomatic bleeding, and 90 day modified Rankin Scale (mRS) scores were evaluated as indicators of outcome.

RESULTS

38 patients with a mean age of 67.5 years were treated with CPD. Mean time from symptom onset to procedure initiation was 226.7 min. Recanalization (TICI 2b-3) was achieved in 27 patients (71.1%). The median NIHSS score on admission was 20. Rates of symptomatic and asymptomatic intracerebral hemorrhage were 7.9% and 13.2%, respectively. The 90 day clinical follow-up data were available for 37 patients. The 90 day mortality rate was 18.9%, and the 90 day clinically acceptable functional outcome (mRS score ≤2) rate was 43.2% (mRS score 0-3, 54.1%). Very distal thrombectomy involving the cortical arteries was performed on four patients without complications.

CONCLUSIONS

Our initial experience suggests that mechanical thrombectomy with the CPD improves 90 day outcomes of patients with AIS by facilitating effective recanalization.

Endovascular Management vs Intravenous Thrombolysis for Acute Stroke Secondary to Carotid Artery Dissection: Local Experience and Systematic Review

BACKGROUND

Little is known regarding the endovascular management of acute ischemic stroke (AIS) related to carotid artery dissection (CAD).

OBJECTIVE

To report our interventional experience in AIS from CAD and to compare it with conservative treatment of CAD with intravenous thrombolysis (IVT) via systematic review.

METHODS

Retrospective analysis of consecutive high-grade steno-occlusive CAD with National Institutes of Health Stroke Scale (NIHSS) >5 and ≤12 hours of last seen normal from 2 tertiary centers. A systematic review for studies on IVT in the setting of CAD via PubMed was performed for comparison.

RESULTS

Of 1112 patients treated with endovascular interventions within the study period, 21 met the inclusion criteria. Mean age was 52.0 ± 10.9 years, 76% were male, NIHSS was 17.4 ± 5.8, 52% received IVT before intervention, and 90% had tandem occlusions. Mean time from last-known-normal to puncture was 4.8 ± 2.1 hours and procedure length 1.8 ± 1.0 hours. Stents were used in 52% of cases, and reperfusion (modified Treatment in Cerebral Ischemia 2b-3) achieved in 95%. No parenchymal hemorrhages were observed and 71% achieved good outcome (90-day modified Rankin Scale 0-2). The literature review identified 8 studies concerning thrombolysis in the CAD setting fitting inclusion criteria (n = 133). Our endovascular experience compared with the pooled IVT reports indicated that, despite presenting with higher NIHSS (17 vs 14; P = .04) and experiencing a longer time to definitive therapy (287 vs 162 minutes; P < .01), patients treated intra-arterially had similar rates of symptomatic cerebral/European Cooperative Acute Stroke Study-parenchymal hematoma 2 hemorrhage (0% vs 6%; P = .43) and good outcomes (71% vs 52%; P = .05).

CONCLUSION

Our study provides evidence that the endovascular management of AIS in the setting of CAD is a feasible, safe, and promising strategy.

Acute endovascular treatment delivery to ischemic stroke patients transferred within a telestroke network: a retrospective observational study

Background Five randomized controlled trials recently demonstrated efficacy of endovascular treatment in acute ischemic stroke. Telestroke networks can improve stroke care in rural areas but their role in patients undergoing endovascular treatment is unknown. Aim We compared clinical outcomes of endovascular treatment between anterior circulation stroke patients transferred after teleconsultation and those directly admitted to a tertiary stroke center. Methods Data derived from consecutive patients with intracranial large vessel occlusion who underwent endovascular treatment from January 2010 to December 2014 at our tertiary stroke center. We compared baseline characteristics, onset-to-treatment times, symptomatic intracranial hemorrhage, in-hospital mortality, reperfusion (modified Treatment in Cerebral Infarction 2b/3), and favorable functional outcome (modified Rankin scale ≤ 2) at discharge between patients transferred from spoke hospitals and those directly admitted. Results We studied 151 patients who underwent emergent endovascular treatment for anterior circulation stroke: median age 70 years (interquartile range, 62-75); 55% men; median National Institutes of Health Stroke Scale score 15 (12-20). Of these, 48 (31.8%) patients were transferred after teleconsultation and 103 (68.2%) were primarily admitted to our emergency department. Transferred patients were younger (p = 0.020), received more frequently intravenous tissue plasminogen activator (p = 0.008), had prolonged time from stroke onset to endovascular treatment initiation (p < 0.0001) and tended to have lower rates of symptomatic intracranial hemorrhage (4.2% vs. 11.7%; p = 0.227) and mortality (8.3% vs. 22.6%; p = 0.041) than directly admitted patients. Similar rates of reperfusion (56.2% vs. 61.2%; p = 0.567) and favorable functional outcome (18.8% vs. 13.7%; p = 0.470) were observed in telestroke patients and those who were directly admitted. Conclusions Telestroke networks may enable delivery of endovascular treatment to selected ischemic stroke patients transferred from remote hospitals that is equitable to patients admitted directly to tertiary hospitals.