Thrombus Neutrophil Extracellular Traps Content Impair tPA-Induced Thrombolysis in Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Neutrophil Extracellular Traps (NETs) are DNA extracellular networks decorated with histones and granular proteins produced by activated neutrophils. NETs have been identified as major triggers and structural factors of thrombosis. A recent study designated extracellular DNA threads from NETs as a potential therapeutic target for improving tissue-type plasminogen activator (tPA)-induced thrombolysis in acute coronary syndrome. The aim of this study was to assess the presence of NETs in thrombi retrieved during endovascular therapy in patients with acute ischemic stroke (AIS) and their impact on tPA-induced thrombolysis.

METHODS

We analyzed thrombi from 108 AIS patients treated with endovascular therapy. Thrombi were characterized by hematoxylin/eosin staining, immunostaining, and ex vivo enzymatic assay. Additionally, we assessed ex vivo the impact of deoxyribonuclease 1 (DNAse 1) on thrombolysis of AIS thrombi.

RESULTS

Histological analysis revealed that NETs contributed to the composition of all AIS thrombi especially in their outer layers. Quantitative measurement of thrombus NETs content was not associated with clinical outcome or AIS pathogenesis but correlated significantly with endovascular therapy procedure length and device number of passes. Ex vivo, recombinant DNAse 1 accelerated tPA-induced thrombolysis, whereas DNAse 1 alone was ineffective.

CONCLUSIONS

This study suggests that thrombus NETs content may be responsible for reperfusion resistance, including mechanical or pharmacological approaches with intravenous tPA, irrespectively of their etiology. The efficacy of a strategy involving an administration of DNAse 1 in addition to tPA should be explored in the setting of AIS.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02907736.

Impact of Modified TICI 3 versus Modified TICI 2b Reperfusion Score to Predict Good Outcome following Endovascular Therapy

BACKGROUND AND PURPOSE

The TICI score is widely used to evaluate cerebral perfusion before and after the endovascular treatment of stroke. Recent studies showing the effectiveness and safety of mechanical thrombectomy combine modified TICI 2b and modified TICI 3 to assess the technical success of endovascular treatment. The purpose of this study was to determine how much clinical outcomes differ between patients achieving modified TICI 2b and modified TICI 3 reperfusion.

MATERIALS AND METHODS

We analyzed 222 consecutive patients with acute large intracranial artery occlusion of the anterior circulation having achieved modified TICI 2b or modified TICI 3 reperfusion after thrombectomy. The primary end point was the rate of favorable outcome defined as the achievement of a modified Rankin Scale score of 0-2 at 3 months.

RESULTS

Patients with modified TICI 3 more often had favorable collateral circulation and atherosclerosis etiology, with a shorter time from onset to reperfusion than patients with modified TICI 2b (all P < .05). The number of total passes to achieve reperfusion was higher in the modified TICI 2b group (median, 2; interquartile range, 1-3, 1-9) versus (median, 1; interquartile range, 1-2, 1-8) in the modified TICI 3 group (P = .0002). Favorable outcome was reached more often for patients with modified TICI 3 than for those with modified TICI 2b (71.7% versus 50.5%, P = .001), with a similar difference when considering excellent outcome. In addition, patients with modified TICI 3 had a lower intracerebral hemorrhage rate (23.0% versus 45.0%, P < .001).

CONCLUSIONS

Patients with modified TICI 3 reperfusion have better functional outcomes than those with modified TICI 2b. Given the improving reperfusion rates obtained with thrombectomy devices, future thrombectomy trials should consider modified TICI 2b and modified TICI 3 status separately.

Treatment of Acute Ischemic Stroke due to Large Vessel Occlusion With COVID-19: Experience From Paris

BACKGROUND AND PURPOSE

Higher rates of strokes have been observed in patients with coronavirus disease 2019 (COVID-19), but data regarding the outcomes of COVID-19 patients suffering from acute ischemic stroke due to large vessel occlusion (LVO) are lacking. We report our initial experience in the treatment of acute ischemic stroke with LVO in patients with COVID-19.

METHODS

All consecutive patients with COVID-19 with acute ischemic stroke due to LVO treated in our institution during the 6 first weeks of the COVID-19 outbreak were included. Baseline clinical and radiological findings, treatment, and short-term outcomes are reported.

RESULTS

We identified 10 patients with confirmed COVID-19 treated for an acute ischemic stroke due to LVO. Eight were men, with a median age of 59.5 years. Seven had none or mild symptoms of COVID-19 at stroke onset. Median time from COVID-19 symptoms to stroke onset was 6 days. All patients had brain imaging within 3 hours from symptoms onset. Five patients had multi-territory LVO. Five received intravenous alteplase. All patients had mechanical thrombectomy. Nine patients achieved successful recanalization (mTICI2B-3), none experienced early neurological improvement, 4 had early cerebral reocclusion, and a total of 6 patients (60%) died in the hospital.

CONCLUSIONS

Best medical care including early intravenous thrombolysis, and successful and prompt recanalization achieved with mechanical thrombectomy, resulted in poor outcomes in patients with COVID-19. Although our results require further confirmation, a different pharmacological approach (antiplatelet or other) should be investigated to take in account inflammatory and coagulation disorders associated with COVID-19.

Modified Thrombolysis in Cerebral Infarction 2C/Thrombolysis in Cerebral Infarction 3 Reperfusion Should Be the Aim of Mechanical Thrombectomy

Background and Purpose—

Although successful reperfusion is usually defined as a modified Thrombolysis in Cerebral Infarction (mTICI) 2B or 3 at the end of the procedure, studies have shown that mTICI 2B patients had poorer functional outcomes than TICI 3 patients. An mTICI 2C category has been recently introduced for patients with near-complete perfusion except for slow flow in a few distal cortical vessels or presence of small distal cortical emboli after mechanical thrombectomy. The purpose of this study was to evaluate the difference in functional outcome between patients achieving successful reperfusion (ie, mTICI 2B, mTICI 2C, and TICI 3 scores).

Methods—

Ancillary study from the ASTER (Contact Aspiration Versus Stent Retriever for Successful Revascularization) prospective multicenter blinded end point trial. Reperfusion results are reported as the mTICI score, including the mTICI 2C grade. Primary outcome was the percentage of patients with favorable outcome defined as a 90-day modified Rankin Scale score of 0 to 2.

Results—

Two hundred ninety patients with successful reperfusion (mTICI ≥2B), harboring ischemic stroke secondary to occlusion of the anterior circulation within 6 hours of onset of symptoms, undergoing mechanical thrombectomy by contact aspiration or stent retriever were included. Favorable outcome (pre-specified as primary outcome of this ancillary study) did not differ significantly between the 3 reperfusion grades, with a similar positive effect of 2C (odds ratio, 1.71; 95% confidence interval, 0.98–3.00) and 3 (odds ratio, 1.73; 95% confidence interval, 0.88–3.41) grades compared with 2B grade. After combining grades 2C and 3, patients had a significantly higher rate of favorable outcome than patients with 2B (odds ratio, 1.72; 95% confidence interval, 1.01–2.90; P =0.043). Favorable outcome rate decreased with increasing onset-to-reperfusion time, with no significant interaction between mTICI 2C/3 grade and onset-to-reperfusion time on favorable outcome.

Conclusions—

Combining mTICI 2C and TICI 3 grades helps to determine a subgroup of patients achieving better functional outcomes than mTICI 2B patients. Achieving mTICI 2C/3 reperfusion should be the new aim of mechanical thrombectomy for anterior circulation LVO.

Successful Reperfusion With Mechanical Thrombectomy Is Associated With Reduced Disability and Mortality in Patients With Pretreatment Diffusion-Weighted Imaging–Alberta Stroke Program Early Computed Tomography Score ≤6

Background and Purpose—

In acute ischemic stroke patients, diffusion-weighted imaging (DWI)–Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is correlated with infarct volume and is an independent factor of functional outcome. Patients with pretreatment DWI-ASPECTS ≤6 were excluded or under-represented in the recent randomized mechanical thrombectomy trials. Our aim was to assess the impact of reperfusion in pretreatment DWI-ASPECTS ≤6 patients treated with mechanical thrombectomy.

Methods—

We analyzed data collected between January 2012 and August 2015 in a bicentric prospective clinical registry of consecutive acute ischemic stroke patients treated with mechanical thrombectomy. Every patient with a documented internal carotid artery or middle cerebral artery occlusion with pretreatment DWI-ASPECTS ≤6 was eligible for this study. The primary end point was a favorable outcome defined by a modified Rankin Scale score ≤2 at 90 days.

Results—

Two hundred and eighteen patients with a DWI-ASPECTS ≤6 were included. Among them, 145 (66%) patients had successful reperfusion at the end of mechanical thrombectomy. Reperfused patients had an increased rate of favorable outcome (38.7% versus 17.4%; P =0.002) and a decreased rate of mortality at 3 months (22.5% versus 39.1%; P =0.013) compared with nonreperfused patients. The symptomatic intracranial hemorrhage rate was not different between the 2 groups (13.0% versus 14.1%; P =0.83). However, in patients with DWI-ASPECTS <5, favorable outcome was low (13.0% versus 9.5%; P =0.68) with a high mortality rate (45.7% versus 57.1%; P =0.38) with or without successful reperfusion.

Conclusions—

Successful reperfusion is associated with reduced mortality and disability in patients with a pretreatment DWI-ASPECTS ≤6. Further data from randomized studies are needed, particularly in patients with DWI-ASPECTS <5.

Mortality and Disability According to Baseline Blood Pressure in Acute Ischemic Stroke Patients Treated by Thrombectomy: A Collaborative Pooled Analysis

BACKGROUND

High blood pressure (BP) is associated with worse clinical outcomes in the setting of acute ischemic stroke, but the optimal blood pressure target is still a matter of debate. We aimed to study the association between baseline BP and mortality in acute ischemic stroke patients treated by mechanical thrombectomy.

METHODS AND RESULTS

A total of 1332 acute ischemic stroke patients treated by mechanical thrombectomy were enrolled (from January 2012 to June 2016) in the ETIS (Endovascular Treatment in Ischemic Stroke) registry. Linear and polynomial logistic regression models were used to assess the association between BP and mortality and functional outcome at 90 days. Highest mortality was found at lower and higher baseline systolic blood pressure (SBP) values following a J- or U-shaped relationship, with a nadir at 157 mm Hg (95% confidence interval 143-170). When SBP values were categorized in 10-mm Hg increments, the odds ratio for all-cause mortality was 3.78 (95% confidence interval 1.50-9.55) for SBP<110 mm Hg and 1.81 (95% confidence interval 1.01-3.36) for SBP≥180 mm Hg using SBP≥150 to 160 mm Hg as reference. The rate of favorable outcome was the highest at low SBP values and lowest at high SBP values, with a nonlinear relationship; in unplanned exploratory analysis, an optimal threshold SBP≥177 mm Hg was found to predict unfavorable outcome (adjusted odds ratio 0.47; 95% confidence interval 0.31-0.70).

CONCLUSION

In acute ischemic stroke patients treated by mechanical thrombectomy, baseline SBP is associated with all-cause mortality and favorable outcome. In contrast to mortality, favorable outcome rate was the highest at low SBP values and lowest at high SBP values. Further studies are warranted to confirm these findings.

Predictors of Parenchymal Hematoma After Mechanical Thrombectomy: A Multicenter Study

Background and Purpose

Parenchymal hematoma (PH) is a rare but dreadful complication of acute ischemic stroke with unclear underlying mechanisms. We aimed to study the incidence and predictors of PH after mechanical thrombectomy.

Methods

Data from a prospective observational multicenter registry was screened to identify acute ischemic stroke patients with an anterior circulation large vessel occlusion who underwent mechanical thrombectomy. Clinical, imaging, and procedural characteristics were used for the analysis, including brain imaging systematically performed at 24 hours. PH occurrence was assessed according to ECASS (European Collaborative Acute Stroke Study) criteria. Univariate and multivariable analyses were performed to identify predictors of PH.

Results

A total of 1316 patients were included in the study. PH occurred in 153 out of 1316 patients (11.6%) and was associated with a lower rate of favorable outcome and increased mortality. On multivariable analysis, age (per 1 year increase, odds ratio [OR], 1.01; 95% CI, 1.00–1.03; P=0.05), current smoking (OR, 2.02; 95% CI, 1.32–3.09; P<0.01), admission Alberta Stroke Program Early CT Score (per a decrease of 1 point, OR, 1.70; 95% CI, 1.18–2.44; P<0.01), general anesthesia (OR, 1.98; 95% CI, 1.36–2.90; P<0.001), angiographic poor collaterals (OR, 2.13; 95% CI, 1.36–3.33; P<0.001) and embolization in new territory (OR, 2.94; 95% CI, 1.70–5.10; P<0.001) were identified as independent predictors of PH.

Conclusions

PH occurred at a rate of 11.6% after mechanical thrombectomy, with high morbidity and mortality. Our study identified clinical, radiological, and procedural predictors of PH occurrence that can serve as the focus of future periprocedural management studies with the aim of reducing its occurrence.

Contact Aspiration Versus Stent Retriever in Patients With Acute Ischemic Stroke With M2 Occlusion in the ASTER Randomized Trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization)

Background and Purpose—

Middle cerebral artery M2-segment occlusions represent an important subgroup of patients with acute stroke with large-vessel occlusion. The safety of mechanical thrombectomy, especially contact aspiration (CA), in such distal intracranial occlusions is still under debate. We compared reperfusion, adverse events, neurological recovery, and functional outcome of patients with isolated M2 occlusions according to the first-line strategy mechanical thrombectomy devices (CA versus stent retriever [SR]).

Methods—

This is a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). The primary outcome was successful reperfusion at the end of all endovascular procedures, defined as modified Thrombolysis in Cerebral Infarction (mTICI) scores 2b/3. Secondary outcomes were mTICI 2c/3 and mTICI 3, 90-day functional outcome, assessed with the modified Rankin Scale score. Safety outcomes included 90-day mortality and any symptomatic intracerebral hemorrhage.

Results—

Seventy-nine patients were included: 48 were allocated to the CA group and 31 to the SR group. There were no significant differences between CA and SR groups in reperfusion after all endovascular procedures regarding mTICI 2b/3 (89.6% versus 83.9%; P =0.36), mTICI 2c/3 (54.2% versus 54.8%; P =0.90), and mTICI 3 (35.4% versus 41.9%; P =0.36) rates. There were no significant differences between CA and SR groups in 90-day modified Rankin Scale ≤2 rate (54.4% versus 50.0%; P =0.84), 24-hour change in National Institutes of Health Stroke Scale (mean difference, −3.9; 95% confidence interval, −7.9 to 0.01), and Alberta Stroke Program Early Computed Tomography score (mean difference, 0.9; 95% confidence interval, −0.1 to 2.0) scores. Safety parameters were well balanced between the 2 groups except for a higher 90-day mortality rate in the CA group (19.6% versus 3.3%; P =0.078).

Conclusions—

First-line mechanical thrombectomy with CA compared with SR did not result in an increased successful revascularization rate in patients with acute stroke with isolated M2 occlusion.

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.

Middle Meningeal Artery: Anatomy and Variations

The middle meningeal artery is the major human dural artery. Its origin and course can vary a great deal in relation, not only with the embryologic development of the hyostapedial system, but also because of the relationship of this system with the ICA, ophthalmic artery, trigeminal artery, and inferolateral trunk. After summarizing these systems in the first part our review, our purpose is to describe, in this second part, the anatomy, the possible origins, and courses of the middle meningeal artery. This review is enriched by the correlation of each variant to the related embryologic explanation as well as by some clinical cases shown in the figures. We discuss, in conclusion, some clinical conditions that require detailed knowledge of possible variants of the middle meningeal artery.

Impact of Reperfusion for Nonagenarians Treated by Mechanical Thrombectomy

Background and Purpose—

Nonagenarians represent a growing stroke population characterized by a higher frailty. Although endovascular therapy (ET) is a cornerstone of the management of acute ischemic stroke related to large vessel occlusion, the benefit of reperfusion among nonagenarians is poorly documented. We aimed to assess the impact of ET-related reperfusion on the functional outcome of reperfusion in this elderly population.

Methods—

A retrospective analysis of clinical and imaging data from all patients aged over 90 included in the ETIS (Endovascular Treatment in Ischemic Stroke) registry between October 2013 and April 2018 was performed. Association between post-ET reperfusion and favorable (modified Rankin Scale [0–2] or equal to prestroke value) and good (modified Rankin Scale [0–3] or equal to prestroke value) outcome were evaluated. Demographic and procedural predictors of functional outcome, including the first-pass effect, were evaluated. Results were adjusted for center, admission National Institutes of Health Stroke Scale, and use of intravenous thrombolysis.

Results—

Among the 124 nonagenarians treated with ET, those with successful reperfusion had the lowest 90-day modified Rankin Scale (odds ratio, 3.26; 95% CI, 1.04–10.25). Only patients with successful reperfusion after the first pass (n=53, 56.7%) had a reduced 90-day mortality (odds ratio, 0.15; 95% CI, 0.05–0.45) and an increased rate of good outcome (odds ratio, 4.55; 95% CI, 1.38–15.03). No increase in the rate of intracranial hemorrhage was observed among patients successfully reperfused.

Conclusions—

Successful reperfusion improves the functional outcome of nonagenarians who should not be excluded from ET. The first-pass effect should be considered in the procedural management of this frail population.

Direct aspiration stroke thrombectomy: a comprehensive review

Mechanical thrombectomy is now the standard of care for acute ischemic stroke patients with large vessel occlusions, and can be performed with several devices and techniques. One of these techniques, direct aspiration (DA), consists of navigating a large-bore catheter up to the face of the clot and initiating forceful suction. This comprehensive review has three objectives: (1) to describe the direct aspiration technique; (2) to present the available evidence regarding predictive factors of DA success and performance compared with other techniques; and (3) to discuss the forthcoming improvements in distal aspiration.

Early Brain Imaging Shows Increased Severity of Acute Ischemic Strokes With Large Vessel Occlusion in COVID-19 Patients

BACKGROUND AND PURPOSE

Reports are emerging regarding the association of acute ischemic strokes with large vessel occlusion and coronavirus disease 2019 (COVID-19). While a higher severity of these patients could be expected from the addition of both respiratory and neurological injury, COVID-19 patients with strokes can present with mild or none respiratory symptoms. We aimed to compare anterior circulation large vessel occlusion strokes severity between patients with and without COVID-19.

METHODS

We performed a comparative cohort study between patients with COVID-19 who had anterior circulation large vessel occlusion and early brain imaging within 3 hours from onset, in our institution during the 6 first weeks of the COVID-19 outbreak and a control group admitted during the same calendar period in 2019.

RESULTS

Twelve COVID-19 patients with anterior circulation large vessel occlusion and early brain imaging were included during the study period and compared with 34 control patients with anterior circulation large vessel occlusion and early brain imaging in 2019. Patients in the COVID-19 group were younger (P=0.032) and had a history of diabetes mellitus more frequently (P=0.039). Patients did not significantly differ on initial National Institutes of Health Stroke Scale nor time from onset to imaging (P=0.18 and P=0.6, respectively). Patients with COVID-19 had more severe strokes than patients without COVID-19, with a significantly lower clot burden score (median: 6.5 versus 8, P=0.016), higher rate of multivessel occlusion (50% versus 8.8%, P=0.005), lower DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Scores; median: 5 versus 8, P=0.006), and higher infarct core volume (median: 58 versus 6 mL, P=0.004). Successful recanalization rate was similar in both groups (P=0.767). In-hospital mortality was higher in the COVID-19 patients' group (41.7% versus 11.8%, P=0.025).

CONCLUSIONS

Early brain imaging showed higher severity large vessel occlusion strokes in patients with COVID-19. Given the massive number of infected patients, concerns should be raised about the coming neurovascular impact of the pandemic worldwide.

Is Reperfusion Useful in Ischaemic Stroke Patients Presenting with a Low National Institutes of Health Stroke Scale and a Proximal Large Vessel Occlusion of the Anterior Circulation?

Background: In population-based studies, patients presenting with minor or mild stroke symptoms represent about two-thirds of stroke patients, and almost one-third of these patients are unable to ambulate independently at the time of discharge. Although mechanical thrombectomy (MT) has become the standard of care for acute ischaemic stroke with proximal large vessel occlusion (LVO) in the anterior circulation, the management of patients harbouring proximal occlusion and minor-to-mild stroke symptoms has not yet been determined by recent trials. The purpose of this study was to evaluate the impact of reperfusion on clinical outcome in low National Institutes of Health Stroke Scale (NIHSS) patients treated with MT. Methods: We analysed 138 consecutive patients with acute LVO of the anterior circulation (middle cerebral artery M1 or M2 segment, internal carotid artery or tandem occlusion) with NIHSS <8, having undergone MT in 3 different centres. Reperfusion was graded using the modified thrombolysis in cerebral infarction (TICI) score and 3 grades were defined, ranging from failed or poor reperfusion (TICI 0, 1, 2A) to complete reperfusion (TICI 3). The primary clinical endpoint was an excellent outcome defined as a modified Rankin score (mRs) 0-1 at 3-months. The impact of reperfusion grade was assessed in univariate and multivariate analyses. The secondary endpoints included favourable functional outcome (90-day mRS 0-2), death and safety concerns. Results: Successful reperfusion was achieved in 81.2% of patients (TICI 2B, n = 47; TICI 3, n = 65). Excellent outcome (mRs 0-1) was achieved in 69 patients (65.0%) and favourable outcome (mRs ≤2) in 108 (78.3%). Death occurred in 7 (5.1%). Excellent outcome increased with reperfusion grades, with a rate of 34.6% in patients with failed/poor reperfusion, 61.7% in patients with TICI 2B reperfusion, and 78.5% in patients with TICI 3 reperfusion (p < 0.001). In multivariate analysis adjusted for patient characteristics associated with excellent outcome, the reperfusion grade remained significantly associated with an increase in excellent outcome; the OR (95% CI) was 3.09 (1.06-9.03) for TICI 2B and 6.66 (2.27-19.48) for TICI 3, using the failed/poor reperfusion grade as reference. Similar results were found regarding favourable outcome (90-day mRs 0-2) or overall mRS distribution (shift analysis). Conclusion: Successful reperfusion is strongly associated with better functional outcome among patients with proximal LVO in the anterior circulation and minor-to-mild stroke symptoms. Randomized controlled studies are mandatory to assess the benefit of MT compared with optimal medical management in this subset of patients.

Anterior cerebral artery embolism during thrombectomy increases disability and mortality

Objective

During thrombectomy, thromboembolic migration in previously unaffected territory may occur and is not systematically notified. We report our data on the incidence, predictors, and clinical outcome of anterior cerebral artery emboli (ACAE).

Methods

From a prospectively collected thrombectomy database of consecutive patients with anterior circulation stroke between January 2012 and December 2016, 690 angiographic images were analyzed to assess ACAE. The primary outcome was a favorable outcome, defined as a 3 month modified Rankin Scale score of 0–2 or equal to the pre-stroke score.

Results

ACAE occurred in 65 patients (9.4%; 95% CI 7.2% to 11.6%). Internal carotid artery occlusion (tandem or terminal), Alberta Stroke Program Early CT Score <7, increasing number of passes, and use of stent retriever alone (compared with distal aspiration alone or combined with stent retriever) were found to be independent predictors of ACAE. Compared with patients without ACAE, patients with ACAE had lower rates, with an adjusted OR (95% CI) of 0.48 (0.25 to 0.92; P=0.027) for favorable outcome and 0.49 (0.25 to 0.96; P=0.038) for early neurologic improvement. ACAE was significantly associated with a higher mortality (adjusted OR 1.93; 95% CI 1.03 to 3.61; P=0.039) and intracranial hemorrhagic complications (adjusted OR 2.45; 95% CI 1.33 to 4.47; P=0.004). Despite a successful reperfusion modified Thrombolysis in Cerebral Infarction score of 2b–3 at the end of the procedure, a favorable outcome was reached in 30% of patients with ACAE compared with 52.4% in the other patients (OR 0.39; 95% CI 0.19 to 0.78; P=0.008).

Conclusions

Procedural ACAE was not an uncommon condition, and was associated with increased mortality and disability rates, regardless of the success of reperfusion.

DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) Mismatch in Thrombectomy Candidates: An Intrarater and Interrater Agreement Study

BACKGROUND AND PURPOSE

We aimed to study the intrarater and interrater agreement of clinicians attributing DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) mismatch in patients with acute ischemic stroke referred for mechanical thrombectomy.

METHODS

Eighteen raters independently scored anonymized magnetic resonance imaging scans of 30 participants from a multicentre thrombectomy trial, in 2 different reading sessions. Agreement was measured using Fleiss κ and Cohen κ statistics.

RESULTS

Interrater agreement for DWI-ASPECTS was slight (κ=0.17 [0.14-0.21]). Four raters (22.2%) had a substantial (or higher) intrarater agreement. Dichotomization of the DWI-ASPECTS (0-5 versus 6-10 or 0-6 versus 7-10) increased the interrater agreement to a substantial level (κ=0.62 [0.48-0.75] and 0.68 [0.55-0.79], respectively) and more raters reached a substantial (or higher) intrarater agreement (17/18 raters [94.4%]). Interrater agreement for DWI-FLAIR mismatch was moderate (κ=0.43 [0.33-0.57]); 11 raters (61.1%) reached a substantial (or higher) intrarater agreement.

CONCLUSIONS

Agreement between clinicians assessing DWI-ASPECTS and DWI-FLAIR mismatch may not be sufficient to make repeatable clinical decisions in mechanical thrombectomy. The dichotomization of the DWI-ASPECTS (0-5 versus 0-6 or 0-6 versus 7-10) improved interrater and intrarater agreement, however, its relevance for patients selection for mechanical thrombectomy needs to be validated in a randomized trial.

Endovascular Management of Acute Ischemic Strokes with Tandem Occlusions

BACKGROUND

Ischemic strokes with tandem occlusions are associated with a poor prognosis. Recent studies demonstrating the effectiveness of endovascular treatment for large vessel occlusions have shown less impressive results in patients with tandem occlusions than in those with isolated intracranial occlusions. Also, the indications and effects of carotid stenting remain unclear.

METHODS

From a prospectively gathered registry, we analyzed data of 70 consecutive patients who underwent mechanical endovascular treatment for acute stroke with tandem occlusions from November 2011 to August 2014. Clinical (including demographics, National Institutes of Health Stroke Scale (NIHSS), and stroke etiology), imaging (including diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score), and endovascular treatment data were assessed and reviewed in consensus by 2 observers. Good clinical outcome was defined as a modified Rankin Scale of ≤2 at 3-month follow-up.

RESULTS

At 3-month follow-up, 50.8% had a poor clinical outcome, including death in 13.4%. Lower NIHSS (initial, at day 1, and at discharge) and successful recanalization (thrombolysis in cerebral infarction 2b-3) were associated with a good clinical outcome (p < 0.05). There were no statistically significant differences between patients with a good or poor clinical outcome in terms of intravenous (IV) tissue plasminogen activator use, delay between symptom onset and recanalization, and endovascular technique including the carotid stenting.

CONCLUSIONS

Despite the recent randomized control trials demonstrating the effectiveness of thrombectomy, there is still a research gap about tandem occlusions. This subtype of stroke, which usually responds poorly to IV thrombolysis, is also difficult to treat by endovascular means. Guidelines for the endovascular management of tandem occlusions are needed.

Prognostic Significance of Pulse Pressure Variability During Mechanical Thrombectomy in Acute Ischemic Stroke Patients

Background Studies on the role of blood pressure ( BP ) variability specifically during mechanical thrombectomy ( MT ) are sparse and limited. Moreover, pulse pressure ( PP ) has not been considered as a potent hemodynamic parameter to describe BP variability during MT . We assessed the impact of PP variability on functional outcome in acute ischemic stroke patients with large vessel occlusion during MT . Methods and Results Acute ischemic stroke patients presenting with large vessel occlusion from January 2012 to June 2016 were included. BP data during MT were prospectively collected in the ETIS (Endovascular Treatment in Ischemic Stroke) registry. Logistic regression models were used to assess the association between PP coefficients of variation and functional outcome at 3 months (modified Rankin Scale). Among the 343 included patients, PP variability was significantly associated with worse 3-month modified Rankin Scale in univariable (odds ratio [OR] =1.56, 95% confidence interval [CI]: 1.24-1.96 per 1-unit increase, P=0.0002) and multivariable ordinal logistic regression (adjusted OR =1.40, 95% CI : 1.09-1.79, P=0.008). PP variability was also associated with unfavorable outcome (modified Rankin Scale 3-6) in univariable ( OR =1.53, 95% CI : 1.17-2.01, P=0.002) and multivariable analysis (adjusted OR =1.42, 95% CI : 1.02-1.98, P=0.04). There was an association between PP variability and 3-month all-cause mortality in univariable analysis ( OR = 1.37, 95% CI : 1.01-1.85 per 1-unit increase of the coefficient of variation of the PP , P=0.04), which did not remain significant after adjustment for potential confounders. Conclusions PP variability during MT is an independent predictor of worse clinical outcome in acute ischemic stroke patients. These findings support the need for a close monitoring of BP variability during MT . Whether pharmacological interventions aiming at reducing BP variability during MT could impact functional outcome needs to be determined.

Effect of Steady and Dynamic Blood Pressure Parameters During Thrombectomy According to the Collateral Status

Background and Purpose- Guidelines regarding blood pressure (BP) management during endovascular therapy (EVT) for anterior circulation strokes are questionable since the optimal BP target is a matter of debate. To evaluate the importance of hemodynamic control during EVT, we investigated the impact of dynamic and steady BP parameters during EVT on functional outcome (part 1) and according to the collateral status (CS; part 2). Methods- We performed a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Recanalization). BP was measured noninvasively during EVT and CS assessed on the angiographic run before EVT. We studied dynamic BP parameter using BP variability (coefficient of variation) and steady BP parameter (hypotension time defined as systolic BP <140 mm Hg and mean arterial pressure <90 mm Hg). The primary outcome was favorable outcome defined as a 3-month modified Rankin Scale score between 0 and 2. Results- Among the 381 patients of the ASTER study, 172 patients were included in part 1 and 159 in part 2. Systolic BP, diastolic BP, and mean arterial pressure variability were negatively associated with favorable outcome regardless of CS: per 10-unit increase, adjusted odds ratios were 0.45 (95% CI, 0.20-0.98), 0.37 (95% CI, 0.19-0.72), and 0.35 (95% CI, 0.16-0.76), respectively. According to CS, the hypotension time with periprocedural mean arterial pressure <90 mm Hg was negatively associated with favorable outcome in patients with poor CS (adjusted odds ratio, 0.88 [95% CI, 0.72-1.09]) but not in patients with good CS (adjusted odds ratio, 1.24 [95% CI, 0.91-1.67]; P_het=0.047). Conclusions- The CS did not modify the association between dynamic parameters and functional outcomes, but some findings suggest that the CS modifies the association between steady parameter and functional outcomes. Hypotension time according to the CS was not statistically predictive of poor outcomes but displayed a trend toward worse outcomes for patients with poor CS only.

Double stent assisted coiling of intracranial bifurcation aneurysms in Y and X configurations with the Neuroform ATLAS stent: immediate and mid term angiographic and clinical follow-up

Purpose

Self-expandable stents have broadened the spectrum of endovascular treatment of intracranial aneurysms. However, procedures involving double stenting in Y/X configurations carry a relatively high risk of procedural complications. The Neuroform ATLAS, the evolution of Neuroform EZ, is a nitinol self-expanding hybrid/open cell stent which can be delivered through a low profile 0.017 inch catheter. We present our experience in the treatment of intracranial aneurysms with this stent in Y and X configurations.

Materials and methods

We prospectively maintained a database from consecutive patients who underwent double stent assisted coiling with the Neuroform ATLAS, from July 2015 to February 2019. Clinical and angiographic results were analyzed.

Results

55 patients harboring 55 bifurcation aneurysms were treated with double stenting: 52 ‘Y’ configurations, 3 ‘X’ configurations. Deployment was successful in all cases. Post-treatment control angiography showed complete occlusion in 33 cases (60%), neck remnant in 8 cases (14.5%), and incomplete occlusion in 14 cases (25.4%). The overall symptomatic periprocedural complication rate was 12.7%. 38 aneurysms underwent follow-up (69%, mean duration 16 months): 33 aneurysms (87%) were completely occluded, 3 aneurysms (8%) had a neck remnant, and 2 aneurysms (5%) were incompletely occluded.

Conclusion

The Neuroform ATLAS is an effective device for treatment of bifurcation aneurysms, allowing good conformability, a high level of navigability, and easy mesh crossing to perform Y/X stenting procedures. The rate of procedural complications remains non-negligible, and an indication for a double stenting procedure should be carefully discussed in a multidisciplinary meeting.

Endovascular treatment of cribriform plate dural arteriovenous fistulas: technical difficulties and complications avoidance

OBJECTIVE

Cribriform plate dural arteriovenous fistula (dAVF) is a rare pathology, for which the treatment of choice used to be neurosurgery. Technological advances in micro-catheters and embolic agents permitted new endovascular alternatives.

METHODS

We included all patients treated endovascularly for a cribriform plate dAVF between 2008 and 2013. We retrospectively analysed data focusing on the type of treatment chosen.

RESULTS

Ten patients were treated by endovascular approach, with a need for an additional surgical exclusion of the fistula in two cases. Thirteen embolisation sessions were done. Embolisation of the fistula through an ethmoidal artery was the technique of choice; the catheterism of the ophthalmic artery was impossible in two cases and the embolic agent did not penetrate in four cases. The embolisation through the middle meningeal artery was successful in one case but the tortuosity of this artery prevented good penetration of the embolic agent. Venous approach was successful in all cases but was limited to fistulas with superficial venous drainage.

CONCLUSIONS

Endovascular treatment of cribriform plate dAVF is safe and effective. The embolisation through ethmoidal artery is the method of choice. Branches of the middle meningeal artery are tortuous and prevent the penetration of embolic agent. Venous approach is effective but is limited to cases of failure of the arterial approach.