Mechanical thrombectomy performs similarly in real world practice: a 2016 nationwide study from the Czech Republic

Endovascular thrombectomy in patients with anterior circulation stroke: an emulated real-world comparison

BACKGROUND

Endovascular thrombectomy (EVT) has been proven effective in anterior circulation stroke due to large vessel occlusion (LVO). However, translation from randomized clinical trials (RCTs) with highly selected patients to real-world requires confirmation, particularly to identify associations outside of strict selection criteria.

AIMS

This study aims to compare functional outcomes after EVT in real-world with those reported in RCTs, and to identify associations with functional outcome after EVT outside RCT-criteria.

METHODS

This study analyzed longitudinal German real-world data from the Stroke Research Consortium in Northern Bavaria (STAMINA) cohort from January, 2015 to June, 2019. We conducted a trial emulation, comparing patients with anterior circulation stroke and LVO meeting selection criteria for RCTs investigating EVT (1) predominantly within 6 hours with those from HERMES meta-analysis, and (2) within 6-24 hours with those from AURORA meta-analysis. We (3) analyzed treatment effects of EVT and association with functional outcome in patients treated outside RCT criteria.

RESULTS

Of 598 patients, 281 (47.0%) met RCT-criteria for treatment within 6 hours (hereinafter STAMINA-HERMES), 74 (12.4%) met RCT-criteria for treatment within 6-24 hours (STAMINA-AURORA), and 277 (46.3%) patients received EVT outside RCT-criteria. We observed no difference in rates of functional independence or mortality, comparing STAMINA-HERMES with HERMES meta-analysis (mRS 0-1: n=120/281 [43%] vs. 291/633 [46%], p=0.36; mortality: n=34/281 [12%] vs. 97/633 [15%], p=0.20), and STAMINA-AURORA with AURORA meta-analysis (mRS 0-1: n=26/74 [35%] vs. 122/266 [46%], p=0.10, mortality: n=10/74 [14%] vs. 45/266 [17%], p=0.48). Patients treated outside RCT-criteria had worse outcome (mRS 0-1: n=38/277 [14%], mortality: n=90/277 [32%], both p<0.001); possibly driven by pre-existing functional dependence (n=172/277 [62%]). Compared to matched controls, EVT outside of RCT-criteria was associated with lower mortality (absolute treatment effect: -14%, 95% Confidence Interval [CI] -23 to -5, p<0.01), but not with recovery to functional independence or premorbid functional status (treatment effect: 4%, CI -4 to 11, p=0.34), which was associated with lower NIHSS (Odds ratio [OR] 0.86, CI 0.80-0.92, p<0.001) and age (OR 0.95, CI 0.93-0.98, p=0.002).

CONCLUSIONS

Translation of EVT outcomes reported in RCTs into real-world is possible, however, almost half of patients did not meet trial criteria. Identification of patients who functionally benefit from frequently performed EVT outside RCT-criteria requires further investigation.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04357899.

Mechanical Thrombectomy in Stroke-Retrospective Comparison of Methods: Aspiration vs. Stent Retrievers vs. Combined Method-Is Aspiration the Best Starting Point?

Background: There are three main methods of mechanical thrombectomy (MT): using a stent retriever (SR) only (SO), aspiration catheter (AC) only (AO) and the combined method (CM) using both the SR and AC. This paper describes a real-life, single-center experience using SO, AO and CM during 276 consecutive MTs. Methods: The primary endpoint was the frequency of first-pass complete (FPE TICI3). The secondary endpoints were final mTICI 2b-3, procedure duration, clinical outcome and the total number of device passes. The third aim of this study was to test the association between the clinical outcomes in patients treated with each method and various factors. Results: There was a significant difference (p = 0.016) between the groups' FPE TICI3 rates with 46% mTICI 3 in the AO group, 41% in the CM group and 21% in the SO group. AO resulted in procedure time shortening to a mean duration of 43 min, and the scores were 56 min for CM and 63 min for SO (p < 0.0001). There were no significant differences in clinical outcomes or in-hospital mortality. The analysis showed a correlation between good clinical outcomes and the administration of IVT: OR 1.71 (1.03-2.84) p = 0.039. Patients ≥66 years old had higher odds of a bad outcome compared to younger patients in general (OR, 1.99 95% CI, 1.17-3.38; p = 0.011). FPE TICI3 was associated with good functional outcomes in the whole treated cohort (OR, 1.98; 95% CI, 1.21-3.25; p = 0.006). Conclusions: In our series, AO proved to be the best starting point in most cases. It demonstrates good technical efficacy regarding FPE, it is fast and clinical outcomes seem to be the least age- and FPE TICI3-dependent. It can be easily converted into the combined method, which had the second-best outcomes in our cohort.

Mechanical Thrombectomy for Acute Common Carotid Artery Occlusion

Mechanical thrombectomy (MT) is the standard treatment for acute large occlusion of the cerebral artery. Evidence for the success of this procedure was based on the treatment of patients with internal carotid artery and middle cerebral artery thrombi. There are a few reports on thrombi extending to the common carotid artery (CCA). We document our endovascular procedure and the clinical outcome in seven consecutive patients who underwent MT for CCA thrombi between September 2016 and April 2021. Their mean National Institutes of Health Stroke Scale score was 20.0 (range, 9-30), and the mean diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score on magnetic resonance images was 8.7 (range, 7-10). In six patients, MT of the CCA occlusion was successful, and the mean puncture-to-reperfusion time was 84 minutes (range, 39-211 minutes). In five patients, successful reperfusion was obtained. The mean total pass number was 4.1 (range, 2-7). Due to large thrombi, we performed balloon guide catheter (BGC) occlusion in three patients. Sheath occlusion occurred in two, and thrombus migration into the femoral artery around the sheath was observed in two patients. The mean modified Rankin Scale score 3 months post-stroke was 3.6 (range, 2-5). When the removal of a large CCA thrombus is attempted in a single step, catheter and sheath occlusion may occur, and this increases the risk for critical systemic artery occlusion. Therefore, we suggest that MT be combined with the BGC technique and propose the use of a large aspiration catheter to decrease the volume of the thrombus.

Survival and functional outcome following endovascular thrombectomy for anterior circulation acute ischemic stroke caused by large vessel occlusion in Sweden 2017-2019-a nationwide, prospective, observational study

BACKGROUND

Endovascular thrombectomy (EVT) is standard of care for anterior circulation acute ischemic stroke (AIS) caused by large vessel occlusion (LVO), but data on nationwide performance in routine healthcare are sparse. The study aims were to describe EVT patients with LVO AIS, analyze mortality and functional outcome, and compare results with randomized controlled trials (RCTs).

METHODS

Data from the Riksstroke and the Swedish Endovascular Treatment of Acute Stroke Registry (RSEVAS) on pre-stroke independent patients, with LVO AIS in 2017-2019, defined as occlusion of the intracranial internal carotid artery, or the M1 or M2 segments of the middle cerebral artery, and groin puncture <6 h of onset, were compared to aggregated HERMES collaboration RCT data. We assessed 90-day survival and function, defined by the modified Rankin Scale. Specific analyzes were stratified by occlusion location.

RESULTS

In all, 1011/2560 of RSEVAS patients matched RCT inclusion criteria. Compared with RCT data, patients were older (73 vs. 68), fewer received intravenous thrombolysis (63.1% vs. 83%), and M2 occlusions were more common (24.5% vs. 8%). 90-day survival in RSEVAS was 85.3%, 42.8% achieved good outcome and 5% had symptomatic intracerebral hemorrhage (sICH). Corresponding outcomes in RCT data were 84.7% survival, 46% good outcome, and 4.4% sICH. Functional outcome was most favorable following M2 occlusions.

CONCLUSIONS

EVT patients from our large real-world national dataset differed from RCT patients in several baseline factors including distribution of vascular occlusion site. However, the overall outcome of EVT in our Swedish cohort appeared to well match the pivotal trial findings.

Between-Center Variation in Outcome After Endovascular Treatment of Acute Stroke: Analysis of Two Nationwide Registries

BACKGROUND

Insight in differences in patient outcomes between endovascular thrombectomy (EVT) centers can help to improve stroke care. We assessed between-center variation in functional outcome of patients with acute ischemic stroke who were treated with EVT. We analyzed to what extent this variation may be explained by modifiable center characteristics.

METHODS

We used nationwide registry data of patients with stroke treated with EVT in the Netherlands and in the Czech Republic. Primary outcome was modified Rankin Scale score at 90 days as an indicator of disability. We used multilevel ordinal logistic regression to quantify the between-center variation in outcomes and the impact of patient and center characteristics. Between-center variation was expressed as the relative difference in odds of a more favorable modified Rankin Scale score between a relatively better performing center (75th percentile) and a relatively worse performing center (25th percentile).

RESULTS

We included a total of 4518 patients treated in 33 centers. Adjusted for patient characteristics, the odds of a more favorable outcome in a center at the 75th percentile of the outcome distribution were 1.46 times higher (95% CI, 1.31-1.70) than the odds in a center at the 25th percentile. Adjustment for center characteristics, including the median time between stroke onset and reperfusion per center, decreased this relative difference in odds to 1.30 (95% CI, 1.18-1.50, P=0.01). This translates into an absolute difference in likelihood of good functional outcome of 8% after adjustment for patient characteristics and to 5% after further adjustment for modifiable center characteristics.

CONCLUSIONS

The considerable between-center variation in patient outcomes after EVT for acute ischemic stroke could be largely explained by center-specific characteristics, such as time to reperfusion. Improvement of these parameters may likely result in a decrease in center-specific differences, and an overall improvement in outcome of patients with acute ischemic stroke.

Outcomes of Stroke Thrombectomy Performed by Interventional Radiologists vs Neurointerventional Physicians

PURPOSE

To test the hypothesis that interventional radiologists (IR) have outcomes for endovascular stroke thrombectomy (EVT) similar to Neurointerventional (NI) physicians and could be used to improve availability of thrombectomy.

MATERIALS AND METHODS

Eight hospitals providing EVT performed by IR and NI in the same institution submitted sequential retrospective data limited to the era of modern devices. Good clinical outcome (90 day modified Rankin score 0-2) and successful revascularization (modified Thrombolysis in Cerebral Infarction score > 2b) were compared between specialties, adjusted for treating hospital, patient age, stroke severity, Alberta Stroke Program Early CT Score (ASPECTS), time from symptom onset to door, and clot location. Propensity score matching was used to compare outcomes. A total of 1009 patients were entered (622 treated by IR and 387 treated by NI).

RESULTS

Median stroke onset to puncture was 245 vs 253 minutes (p=.49), technically successful revascularization was 81.8% vs 82.4% (p=.81), and good clinical outcome was 45.5% vs 50.1% (p=.16), respectively. After adjusting, physician specialty was not a significant predictor of good clinical outcome (odds ratio 1.028 [95% CI 0.760-1.390]; p=.86). After matching, mRS 0-2 was 47.7% for IR and 51.1% for NI (p=0.366).

CONCLUSION

There was no significant difference in successful revascularization and good clinical outcomes between IR and NI physicians. Outcomes by IR were similar to NI outcomes from previously published trials and registries. This may be useful to address coverage and access to stroke interventions.

Trends in acute ischemic stroke treatments and mortality in the United States from 2012 to 2018

OBJECTIVE

The establishment of mechanical thrombectomy (MT) as a first-line treatment for select patients with acute ischemic stroke (AIS) and the expansion of stroke systems of care have been major advancements in the care of patients with AIS. In this study, the authors aimed to identify temporal trends in the usage of tissue-type plasminogen activator (tPA) and MT within the AIS population from 2012 to 2018, and the relationship to mortality.

METHODS

Using a nationwide private health insurance database, 117,834 patients who presented with a primary AIS between 2012 and 2018 in the United States were identified. The authors evaluated temporal trends in tPA and MT usage and clinical outcomes stratified by treatment and age using descriptive statistics.

RESULTS

Among patients presenting with AIS in this population, the mean age was 69.1 years (SD ± 12.3 years), and 51.7% were female. Between 2012 and 2018, the use of tPA and MT increased significantly (tPA, 6.3% to 11.8%, p < 0.0001; MT, 1.6% to 5.7%, p < 0.0001). Mortality at 90 days decreased significantly in the overall AIS population (8.7% to 6.7%, p < 0.0001). The largest reduction in 90-day mortality was seen in patients treated with MT (21.4% to 14.1%, p = 0.0414) versus tPA (11.8% to 7.0%, p < 0.0001) versus no treatment (8.3% to 6.3%, p < 0.0001). Age-standardized mortality at 90 days decreased significantly only in patients aged 71-80 years (11.4% to 7.8%, p < 0.0001) and > 81 years (17.8% to 11.6%, p < 0.0001). Mortality at 90 days stagnated in patients aged 18 to 50 years (3.0% to 2.2%, p = 0.4919), 51 to 60 years (3.8% to 3.9%, p = 0.7632), and 61 to 70 years (5.5% to 5.2%, p = 0.2448).

CONCLUSIONS

From 2012 to 2018, use of tPA and MT increased significantly, irrespective of age, while mortality decreased in the entire AIS population. The most dramatic decrease in mortality was seen in the MT-treated population. Age-standardized mortality improved only in patients older than 70 years, with no change in younger patients.

Comparative study of intracranial access in thrombectomy using next generation 0.088 inch guide catheter technology

BACKGROUND

Most conventional 0.088 inch guide catheters cannot safely navigate intracranial vasculature. The objective of this study is to evaluate the safety of stroke thrombectomy using a novel 0.088 inch guide catheter designed for intracranial navigation.

METHODS

This is a multicenter retrospective study, which included patients over 18 years old who underwent thrombectomy for anterior circulation large vessel occlusions. Technical outcomes for patients treated using the TracStar Large Distal Platform (TracStar LDP) or earlier generation TRX LDP were compared with a matched cohort of patients treated with other commonly used guide catheters. The primary outcome measure was device-related complications. Secondary outcome measures included guide catheter failure and time between groin puncture and clot engagement.

RESULTS

Each study arm included 45 patients. The TracStar group was non-inferior to the control group with regard to device-related complications (6.8% vs 8.9%), and the average time to clot engagement was 8.89 min shorter (14.29 vs 23.18 min; p=0.0017). There were no statistically significant differences with regard to other technical outcomes, including time to recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2B). The TracStar was successfully advanced into the intracranial internal carotid artery in 33 cases (73.33%); in three cases (6.67%), it was swapped for an alternate catheter. Successful reperfusion (mTICI 2B-3) was achieved in 95.56% of cases. Ninety-day follow-up data were available for 86.67% of patients, among whom 46.15% had an modified Rankin Score of 0-2%, and 10.26% were deceased.

CONCLUSIONS

Tracstar LDP is safe for use during stroke thrombectomy and was associated with decreased time to clot engagement. Intracranial access was regularly achieved.

Mechanical Thrombectomy in Stroke. Experience from Switching from Stent Retriever Only to Stent Retriever Combined with Aspiration Catheter

Endovascular treatment is a rapidly evolving technique; therefore, there is a constant need to evaluate this method and its modifications. This paper discusses a single-center experience and the results of switching from the stent retriever only (SO) mechanical thrombectomy (MT) to the combined approach (CA), with a stent retriever and aspiration catheters.

METHODS

The study involved a retrospective analysis of 70 patients undergoing MT with the use of either SO or CA. The primary endpoint was the frequency of perfect reperfusion defined as grade 3 of the modified Thrombolysis in Cerebral Infarction scale (mTICI) after the first pass. The secondary endpoints were the procedure success, defined as mTICI grades 2b-3; time of the procedure; clinical outcome, measured by 90 days' modified Rankin Scale (mRS) score; Δ NIHSS, defined as the difference between National Institutes of Health Stroke Scale (NIHSS) score at patients' admission and discharge; and the total number of device passes.

RESULTS

Out of the 70 patients included, 33 were treated with SO and 37 with CA. In both groups, a total number of 42 patients received intravenous recombined tissue plasminogen activator (iv-rTPA: 20 patients (60.6%) in the SO group and 22 patients (59.5%) in the CA group (p = 1.000). There was a significant difference between the groups regarding first-pass success rate, with 46% in the CA group and 18% in the SO group, (OR 3.83, 95% CI 1.28 to 11.44, p = 0.016). Complete procedure success tended to be more frequent in the CA group than in the SO group-94.6% vs. 84.8% (OR 3.13, 95% CI 0.56 to 17.34, p = 0.193)-and CA tended to require a lower number of passes than SO (mean 1.76 vs. 2.09 passes per procedure, p = 0.114), yet these differences did not reach statistical significance. Mean duration of the procedure was significantly shorter in the CA group than in the SO group (49 min vs. 64 min, p = 0.017). There was a significant difference in clinical outcomes, with higher Δ NIHSS (9.3 in the CA group vs. 6.7 in the SO group, p = 0.025) after the procedure and 90-day mRS (median 2 in the CA group vs. 4 in the SO group, p = 0.031).

CONCLUSIONS

Combining stent retrievers with aspiration catheters may offer a beneficial effect on angiographic results and clinical outcomes in stroke patients undergoing endovascular treatment.

Endovascular Thrombectomy Versus Bridging Thrombolysis: Real-World Efficacy and Safety Analysis Based on a Nationwide Registry Study

Background

It was uncertain if direct endovascular thrombectomy (ET) was superior to bridging thrombolysis (BT) for patients with acute ischemic stroke caused by large‐vessel occlusions. We aimed to examine real‐world clinical outcomes of ET using nationwide registry data in China and to compare the efficacy and safety between BT and direct ET.

Methods and Results

Patients treated with ET from a nationwide registry study in China were included. Rapid neurological improvement, intracranial hemorrhage, and in‐hospital mortality were compared between the 2 groups using multivariate logistic models and propensity‐score matching analyses. A total of 7674 patients from 592 stroke centers were included. The median onset‐to‐puncture time, onset‐to‐door time, and door to puncture time were 290, 170, and 99 minutes, respectively. A total of 2069 (27.0%) patients received BT treatment. Patients in the BT group had a significantly shorter onset‐to‐puncture time (235 versus 323 minutes; P<0.001) and onset‐to‐door time (90 versus 222 minutes; P<0.001) compared with the direct ET group. The prior use of intravenous thrombolysis was associated with a higher rate of rapid neurological improvement (adjusted odds ratio [OR], 0.83; 95% CI, 0.71–0.96) and higher risk of intracranial hemorrhage (adjusted OR, 1.46; 95% CI, 1.18–1.80) in multivariate analyses and propensity‐score matching analyses.

Conclusions

This study reflects the current application of ET in China. More patients received direct ET than BT. Our results suggested that favorable short‐term outcomes could be achieved with BT compared with direct ET. Higher risk of intracranial hemorrhage was observed in the BT group.

Endovascular Therapy for Ischemic Stroke Can Be Successfully Performed by Peripheral Vascular Interventionalists

PURPOSE

To describe interventionalist and workflow characteristics of an acute stroke endovascular thrombectomy (EVT) center without a dedicated interventional neuroradiology service and report clinical and radiologic outcomes.

MATERIALS AND METHODS

Retrospective review was performed of all patients receiving EVT at Christchurch Hospital, New Zealand, from June 2014 to the end of December 2019 from a prospective reperfusion registry. During the study period, 5 peripheral vascular interventional radiologists, 2 of whom had experience in other neuroendovascular procedures, performed 210 EVT procedures. Median age of patients was 76 years (interquartile range: 64-83 y), and 107 (51%) were men.

RESULTS

The most commonly occluded vessel was the M1 middle cerebral artery (n = 114; 54%). Successful reperfusion (Modified Treatment In Cerebral Ischemia score 2b-3) was achieved in 180 (86%) procedures. Favorable 90-day outcome (modified Rankin Scale score 0-2) was achieved in 102 (54%) patients with no disability before stroke. Symptomatic intracranial hemorrhage occurred in 3 (1.4%) patients. Treatment rates in the local catchment area increased from 6 per 100,000 population in 2017 to 15 per 100,000 in 2019.

CONCLUSIONS

The results of this study suggest peripheral vascular interventional radiologists with specific training can successfully perform EVT resulting in a significant increase in EVT provision.

Thrombectomy vs medical management in low NIHSS acute anterior circulation stroke

OBJECTIVE

To undertake an effectiveness and safety analysis of EVT in patients with LVO and NIH Stroke Scale (NIHSS) score ≤6 using datasets of multicenter and multinational nature.

METHODS

We pooled patients with anterior circulation occlusion from 3 prospective international cohorts. Patients were eligible if presentation occurred within 12 hours from last known well and baseline NIHSS ≤6. Primary outcome was modified Rankin Scale (mRS) score 0-1 at 90 days. Secondary outcomes included neurologic deterioration at 24 hours (change in NIHSS of ≥2 points), mRS 0-2 at 90 days, and 90-day all-cause mortality. We used propensity score matching to adjust for nonrandomized treatment allocation.

RESULTS

Among 236 patients who fit inclusion criteria, 139 received EVT and 97 received medical management. Compared to medical management, the EVT group was younger (65 vs 72 years; p < 0.001), had more proximal occlusions (p < 0.001), and less frequently received concurrent IV thrombolysis (57.7% vs 71.2%; p = 0.04). After propensity score matching, clinical outcomes between the 2 groups were not significantly different. EVT patients had an 8.6% (95% confidence interval [CI] -8.8% to 26.1%) higher rate of excellent 90-day outcome, despite a 22.3% (95% CI, 3.0%-41.6%) higher risk of neurologic deterioration at 24 hours.

CONCLUSIONS

EVT for LVO in patients with low NIHSS score was associated with increased risk of neurologic deterioration at 24 hours. However, both EVT and medical management resulted in similar proportions of excellent clinical outcomes at 90 days.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for patients with acute anterior circulation ischemic strokes and LVO with NIHSS < 6, EVT and medical management result in similar outcomes at 90 days.

Endovascular Treatment for Acute Ischemic Stroke in Patients on Oral Anticoagulants: Results From the MR CLEAN Registry

Background and Purpose- The use of oral anticoagulants (OAC) is considered a contra-indication for intravenous thrombolytics as acute treatment of ischemic stroke. However, little is known about the risks and benefits of endovascular treatment in patients on prior OAC. We aim to compare outcomes after endovascular treatment between patients with and without prior use of OAC. Methods- Data of patients with acute ischemic stroke caused by an intracranial anterior circulation occlusion, included in the nationwide, prospective, MR CLEAN Registry between March 2014 and November 2017, were analyzed. Outcomes of interest included symptomatic intracranial hemorrhage and functional outcome at 90 days (modified Rankin Scale score). Outcomes between groups were compared with (ordinal) logistic regression analyses, adjusted for prognostic factors. Results- Three thousand one hundred sixty-two patients were included in this study, of whom 502 (16%) used OAC. There was no significant difference in the occurrence of symptomatic intracranial hemorrhage between patients with and without prior OACs (5% versus 6%; adjusted odds ratio, 0.63 [95% CI, 0.38-1.06]). Patients on OACs had worse functional outcomes than patients without OACs (common odds ratio, 0.57 [95% CI, 0.47-0.66]). However, this observed difference in functional outcome disappeared after adjustment for prognostic factors (adjusted common odds ratio, 0.91 [95% CI, 0.74-1.13]). Conclusions- Prior OAC use in patients treated with endovascular treatment for ischemic stroke is not associated with an increased risk of symptomatic intracranial hemorrhage or worse functional outcome compared with no prior OAC use. Therefore, prior OAC use should not be a contra-indication for endovascular treatment.

Effect of time from onset to endovascular therapy on outcomes: the National Acute Stroke Israeli (NASIS)-REVASC registry

Background

Endovascular therapy (EVT) is currently the most effective treatment for emergent large vessel occlusion (ELVO) stroke. Earlier treatment is associated with a better clinical outcome. Our aim was to examine the association between onset-to-EVT (OTE) time and clinical outcomes using real-world nationwide data from the National Acute Stroke ISraeli (NASIS)-REVASC registry.

Methods

Stroke patients undergoing EVT within the Endovascular Capable Centres (ECCs) in Israel between January 2014 and March 2016 were prospectively included. Several clinical and radiological outcomes were evaluated. The association between OTE time and outcomes was analyzed with logistic regression models using time as a continuous variable and then by OTE groups of <2, 2–4, 4–6, and >6 hours.

Results

299 patients with acute stroke were included in the analysis. OTE time was significantly associated with favorable outcomes. ORs for each hour of delay in EVT were 0.84 (95% CI 0.71 to 0.99) for significant early recovery, 0.80 (95% CI 0.68 to 0.94) for discharge to home, 0.80 (95% CI 0.66 to 0.95) for freedom from disability at discharge, and 0.78 (95% CI 0.67 to 0.91) for excellent reperfusion (Thrombolysis in Cerebral Ischemia 3). The <2 OTE group was significantly associated with better outcomes than the ≥2 OTE group including significant early recovery (OR 3.3, 95% CI 1.2 to 9.1), discharge to home (OR 3.32, 95% CI 1.3 to 8.5), and excellent reperfusion (OR 4.6, 95% CI 1.3 to 29.5). The same trend was observed for freedom from disability at discharge and 3 months (OR 2.08, 95% CI 0.7 to 5.7 and OR 2.57, 95% CI 0.8 to 8.3, respectively). Only 1% of transferred patients achieved an OTE time of <2 hours.

Conclusions

Nationwide real-life registry data indicate that benefit from EVT is strongly associated with OTE time and is most prominent within the ‘two golden hours’ from stroke onset. This time goal may not be applicable in inter-hospital transfer patients.

'Real-world' comparison of first-line direct aspiration and stent retriever mechanical thrombectomy for the treatment of acute ischemic stroke in the anterior circulation: a multicenter international retrospective study

BACKGROUND

Thrombectomy for anterior large vessel occlusion less than 24 hours since last known well is now standard of care. Certain aspects of clinical trials may limit generalizability to 'real-world' practice.

OBJECTIVE

To compare revascularization rates and outcomes for direct aspiration (ADAPT) and stent retriever thrombectomy following anterior acute ischemic stroke (AIS) in a real-life setting.

METHODS

Data from the most recent 20 consecutive patients with AIS treated with mechanical thrombectomy between 2015 and 2016 were collected from 15 high-volume stroke centers across North America for a total of 300 cases. Patients with proximal anterior large vessel occlusions were dichotomized by primary treatment technique. Ordinal logistic regression assessed the effects of clinical variables on patient disability using 90-day modified Rankin Scale (mRS) scores.

RESULTS

Adequate revascularization (Thrombolysis in Cerebral Infarction ≥2b) was ultimately achieved in 91.2% of first-line direct aspiration (ADAPT) cases with an average of 1.9±1.9 passes and in 87.5% of stent retriever cases with an average of 1.7±1.0 passes. Time from groin puncture to revascularization was shorter for ADAPT cases. The mean 90-day mRS score for both groups was 3.0±2.4. Number of passes using primary technique, and postintervention intracranial hemorrhage, were significant predictors of 90-day mRS scores after ADAPT, while age and preprocedure mRS score were predictive of outcomes following first-line stent retriever.

CONCLUSIONS

Our data show similar adequate revascularization rates and 90-day functional outcomes for first-line direct aspiration and stent retrievers for anterior large vessel occlusion in a real-world setting. These results support the findings of other prospective trials evaluating the two techniques.

Metallic Hyperdensity Sign on Noncontrast CT Immediately after Mechanical Thrombectomy Predicts Parenchymal Hemorrhage in Patients with Acute Large-Artery Occlusion

BACKGROUND AND PURPOSE

Parenchymal hemorrhage is a severe complication following mechanical recanalization in patients with acute ischemic stroke with large-vessel occlusion. This study aimed to assess whether the metallic hyperdensity sign on noncontrast CT performed immediately after mechanical thrombectomy can predict parenchymal hemorrhage at 24 hours.

MATERIALS AND METHODS

We included consecutive patients with acute ischemic stroke with large-vessel occlusion who underwent noncontrast CT immediately after mechanical thrombectomy between January 2014 and September 2018. The metallic hyperdensity sign was defined as a nonpetechial intracerebral hyperdense lesion (diameter, ≥1 cm) in the basal ganglia and a maximum CT density of >90 HU. The sensitivity, specificity, and positive and negative predictive values of the metallic hyperdensity sign in predicting parenchymal hemorrhage were calculated.

RESULTS

A total of 198 patients were included. The metallic hyperdensity sign was found in 59 (29.7%) patients, and 51 (25.7%) patients had parenchymal hemorrhage at 24 hours. Patients with the metallic hyperdensity sign are more likely to have parenchymal hemorrhage than those without it (76.3% versus 4.3%, P < .001). The sensitivity, specificity, positive predictive value, and negative predictive value of the metallic hyperdensity sign in predicting parenchymal hemorrhage were 88.2%, 90.5%, 76.3%, and 95.7%, respectively.

CONCLUSIONS

The presence of the metallic hyperdensity sign on noncontrast CT performed immediately after mechanical thrombectomy in patients with large-vessel occlusion could predict the occurrence of parenchymal hemorrhage at 24 hours, which might be helpful in postinterventional management within 24 hours after mechanical thrombectomy.

Acute Endovascular Treatment of Patients With Ischemic Stroke From Intracranial Large Vessel Occlusion and Extracranial Carotid Dissection

Introduction: Carotid artery dissection (CAD) and atherosclerotic carotid artery occlusion (ACAO) are major causes of a tandem occlusion in patients with intracranial large vessel occlusion (LVO). Presence of tandem occlusions may hamper intracranial access and potentially increases the risk of procedural complications of endovascular treatment (EVT). Our aim was to assess neurological, functional and technical outcome and complications of EVT for intracranial LVO in patients with CAD in comparison to patients with ACAO and to patients without CAD or ACAO.

Methods: We analyzed data of the MR CLEAN trial intervention arm and MR CLEAN Registry, acquired in 16 Dutch EVT-centers. Primary outcome was the change in stroke severity by comparing the National Institute of Health Stroke Scale (NIHSS) score at 24–48 h after treatment vs. baseline. Secondary outcomes included reperfusion rate and symptomatic intracranial hemorrhage (sICH). We compared outcomes and complications between patients with CAD vs. patients with ACAO and patients without CAD or ACAO.

Results: In total, we identified 74 (4.7%) patients with CAD, 92 (5.9%) patients with ACAO and 1398 (89.4%) patients without CAD or ACAO. Neurological improvement at short-term after EVT in patients with CAD was significantly better compared to ACAO (resp. mean −5 vs. mean −1 NIHSS point; p = 0.03) and did not differ compared to patients without CAD or ACAO (−4 NIHSS points; p = 0.62). Rates of successful reperfusion in patients with CAD (47%) was comparable to patients with ACAO (47%; p = 1.00), but was less often achieved compared to patients without CAD or ACAO (58%; p = 0.08). Occurrence of sICH did not differ significantly between CAD patients (5%) and ACAO (11%; p = 0.33) or without CAD/ACAO (6%; p = 1.00).

Conclusion: EVT in patients with intracranial LVO due to CAD results in neurological improvement comparable to patients without tandem occlusions. Therefore, carotid artery dissection by itself should not be a contraindication for endovascular treatment in stroke patients with intracranial large vessel occlusion. Although more challenging endovascular procedures are to be suspected in both patients with CAD or ACAO, accurate distinction between CAD and ACAO might influence clinical decision making as better clinical outcome can be expected in patients with CAD.

Urgent Middle Cerebral Artery Embolectomy of Calcified Embolus After Intravenous Thrombolysis: 2-Dimensional Operative Video

This video shows an urgent microsurgical embolectomy of the inferior division of the left middle cerebral artery in a patient treated by intravenous thrombolysis (IVT). Patient was eligible for endovascular mechanical thrombectomy¹; however, the interventional radiologist was not comfortable performing the procedure given prior unsuccessful attempts to remove a calcified cerebral embolus.² A 75-yr-old female presented with an acute ischemic stroke with isolated aphasia (NIHSS 9). Using the drip-and-ship concept, IVT (0.9 mg/kg rt-PA) was administered in a regional hospital. Fifty-five minutes after a complete recovery following IVT, multiple transient ischemic attacks of aphasia were observed. While the patient was a candidate for mechanical thrombectomy based on CT perfusion imaging, given the unsuccessful reports in the literature and the interventional radiologist's experience, the decision was made to offer microsurgical embolectomy of the calcified cerebral embolus.³ Informed consent for the procedure was obtained directly from the patient. Calcified, crumbly embolus was removed from a 5 mm longitudinal arteriotomy. The arteriotomy was sutured with interrupted 10-0 suture. Initial flow after the embolectomy was 6.5 mL/min. Upon inspection, a distal kink was found in the M2 and after repositioning, flow improved to 35 mL/min.

Postoperative CT angiography documented complete recanalization. The clinical findings completely resolved (NIHSS 0) within 12 hr and remained unchanged at 3 mo and 1 yr.

Informed consent was obtained from the patient for use of media for educational and publication purposes.

Single-Centre Experience with Patients Selection for Mechanical Thrombectomy Based on Automated Computed Tomography Perfusion Analysis-A Comparison with Computed TomographyCT Perfusion Thrombectomy Trials

BACKGROUND

In randomized clinical trials, mechanical thrombectomy (MT) was proved to be a highly effective treatment of acute ischemic stroke which improved clinical outcomes. Some of the trials used automated computed tomography perfusion (CTP) analysis for selection of participants. We present a single-center experience with CTP selection and comparison with CTP trials.

METHODS

Data of consecutive MT patients (from January 2016 to December 2017) were retrospectively reviewed. All patients with multiphase CT angiography confirmed the presence of anterior circulation large vessel occlusion/s in the intracranial internal carotid artery and/or middle cerebral artery (M1 or M2) and with admission brain CTP analyzed by RAPID software were included into the analysis.

RESULTS

Sixty-two patients fulfilled the inclusion criteria (mean age was 70.1 ± 13.6 years, females 48.5%). At baseline, National Institutes of Health Stroke Scale score was 16 (IQR = 13-20), Alberta Stroke Program Early CT Score (ASPECTS) was 8 (IQR = 7-9), CTP core volume was 20 mL (IQR = 2-36), and CTP penumbra volume was 145.5 mL (IQR = 107-184). Time from stroke onset to imaging was 1 hour 32 minutes, time from stroke onset to reperfusion was 3 hours 50 minutes, and median time from CT to reperfusion was 1 hour 56 minutes. Modified thrombolysis in cerebral infarction 2b/3 was achieved in 42 patients (67.7%). Twenty-three patients (37%) had modified Rankin scale 0-2 at 90 days.

CONCLUSIONS

Our analysis of CTP-selected patients for MT supports clinical applicability of automated CTP analysis into everyday clinical practice.

Comparison of Mechanical Thrombectomy with Contact Aspiration, Stent Retriever, and Combined Procedures in Patients with Large-Vessel Occlusion in Acute Ischemic Stroke

Background

We investigated the properties and effects of 5 mechanical thrombectomy procedures in patients with acute ischemic stroke. The relationships between the type of procedure, the time required, the success of recanalization, and the clinical outcome were analyzed.

Material/Methods

This prospective comparative analysis included 500 patients with acute ischemic stroke and large-vessel occlusion. We compared contact aspiration thrombectomy (ADAPT, n=100), stent retriever first line (SRFL, n=196), the Solumbra technique (n=64), mechanical thrombectomy plus stent implantation (n=81), and a combined procedure (n=59).

Results

ADAPT provided shorter procedure (P<0.001) and recanalization times (P<0.001) than the other techniques. Better clinical outcome was achieved for ischemia in the anterior circulation than ischemia in the posterior fossa (P<0.001). Compared to the other techniques, patients treated with ADAPT procedure had increased odds of achieving better mTICI scores (P=0.002) and clinical outcome (NIHSS) after 7 days (P=0.003); patients treated with SRFL had increased odds of achieving better long-term clinical status (3M-mRS=0–2; P=0.040). Patients with SRFL and intravenous thrombolysis (IVT) had increased odds of better clinical status (3M-mRS=0–2; P=0.031) and decreased odds of death (P=0.005) compared to patients with SRFL without IVT. The other treatment approaches had no additional effect of IVT. Patients with SRFL with a mothership transfer had increased odds of achieving favorable clinical outcome (3M-mRS) compared to SRFL with the drip-and-ship transfer paradigm (P=0.015).

Conclusions

Our results showed that ADAPT and SRFL provided significantly better outcomes compared to the other examined techniques. A mothership transfer and IVT administration contributed to the success of the SRFL approach.

Safety and Outcome of Endovascular Treatment in Prestroke-Dependent Patients

Background and Purpose—

Prestroke dependence is an exclusion criterion in most trials of endovascular treatment (EVT) for acute ischemic stroke. Little is known about outcomes after EVT in these patients. We compared outcome and safety of EVT between prestroke-dependent and prestroke-independent patients.

Methods—

We report patients with an anterior circulation occlusion who were included between March 2014 and June 2016 in the MR CLEAN registry (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke)—a prospective, multicenter, observational study for stroke intervention centers in the Netherlands. Prestroke dependence was defined as modified Rankin Scale score of 3 to 5 before onset of current stroke. Primary outcome was favorable outcome at 90 days, defined as modified Rankin Scale of 0 to 2 or not worsening of the modified Rankin Scale score. Secondary outcomes included National Institutes of Health Stroke Scale score post-intervention, reperfusion grade, and safety outcomes. Logistic regression analyses (adjusted for age, baseline National Institutes of Health Stroke Scale score, collaterals, time to EVT, and intravenous thrombolysis before EVT) were used to assess the association between prestroke dependence and outcomes.

Results—

One thousand four hundred forty-one patients were included in the present study, of whom 157 (11%) were prestroke dependent. Favorable outcome was seen in 27% prestroke-dependent patients, compared with 42% prestroke-independent patients ( P <0.05). After adjustment, prestroke dependence was not associated with less-favorable outcome (OR adjusted , 0.90; 95% CI, 0.58–1.39). The occurrence of symptomatic intracranial hemorrhage and ischemic stroke progression was similar in both groups.

Conclusions—

A substantial proportion of prestroke-dependent patients will reach prestroke modified Rankin Scale scores after EVT, and complication rates are comparable with prestroke-independent patients. Therefore, prestroke-dependent patients should not be routinely excluded from EVT.

Mechanical Thrombectomy for Acute Ischemic Stroke in Czech Republic: Technical Results from the Year 2016

BACKGROUND AND PURPOSE

Experienced multidisciplinary stroke team and well-organized hospital management are considered necessary to achieve good results after mechanical thrombectomy (MT) in acute ischemic stroke patients. We analyzed the technical results of MT performed in the Czech Republic in the year 2016 to provide relevant data for further quality improvement.

MATERIAL AND METHODS

All centers performing MT in the CR were called for detailed technical and clinical data from year 2016, which were anonymously analyzed and relevant technical key time intervals were compared. Clinical outcomes were assessed according to the HERMES meta-analysis.

RESULTS

In the 2016, 1053 MTs were performed in the CR. Of 15 dedicated centers, the data from 12 centers and from 886 (84%) patients (49.2% males, mean age 69.8 ± 12.3 years) were analyzed. The overall median of time from hospital arrival to groin puncture (GP) was 77 min with a range from 40 to 109 min among individual hospitals, from GP to first passage of stent retriever 20 (15-40) min and from GP to maximal reached recanalization 42 (33-80) min. The median of recanalization time was 240 (219-320) min. The recanalization (TICI 2b-3) was achieved in 81.7% of patients, 44.1% of patients had a good 3-month clinical outcome and 6.3% suffered from symptomatic intracerebral hemorrhage. Peri-procedural complications were recorded in 89 (10%) patients.

CONCLUSION

Despite achieved good overall results, a great variability in some of the analyzed key time intervals among individual centers performing MT warrants further quality improvement.