Clinical and radiological predictors of recanalisation and outcome of 40 patients with acute basilar artery occlusion treated with intra-arterial thrombolysis

Early Detection of Hyperdense Basilar Artery Signs Through Comparison With Previous Images

The presence of the hyperdense basilar artery (HDBA) sign, which indicates basilar artery occlusion (BAO), plays an important role in the early diagnosis and intervention in patients with acute ischemic stroke. However, qualitative and quantitative assessment of the HDBA sign is challenging. This case report describes a 60-year-old woman with a history of diabetes mellitus, hypertension, and cerebral infarction. She developed progressive loss of consciousness and ataxic respiration. A noncontrast-enhanced head computed tomography (CT) scan performed three hours after symptom onset revealed the HDBA sign compared with previously obtained CT images. Quantitative measurements revealed a significant increase in Hounsfield units (HUs) in the basilar artery. Subsequent three-dimensional CT angiography confirmed the occlusion of the vertebrobasilar artery. This case highlights the importance of comparing current and previous imaging findings in detecting the HDBA sign. Quantitative HU measurements may further aid diagnosis. Early detection of the HDBA sign on noncontrast-enhanced head CT is critical for expediting the diagnosis and treatment of BAO.

IV Thrombolysis in Basilar Artery Occlusion: Outcomes and Comparison With Endovascular Thrombectomy

BACKGROUND AND OBJECTIVES

Recanalization is considered a prerequisite for favorable outcome in basilar artery occlusion (BAO). Intravenous thrombolysis (IVT) has been successfully used for eligible patients with BAO well beyond the 4.5-hour time window but has been largely underrepresented in the best medical management arms in recent randomized controlled trials of recanalization therapy in BAO. We aimed to analyze the outcomes of patients with BAO treated with IVT only and to compare IVT with endovascular thrombectomy (EVT).

METHODS

This observational single-center, retrospective cohort study included consecutive patients with BAO treated with IVT and/or EVT up to 48 hours of symptom onset during 1995-2022. The primary outcome was favorable functional outcome (modified Rankin Scale 0-3) at 3 months collected by a stroke physician by phone. In the first part, we described the outcomes and factors associated with functional outcome in the IVT-only cohort during 1995-2022. In the second part, we used doubly robust inverse probability-weighted regression adjustment models to compare functional outcome of patients treated with IVT vs EVT+/-IVT during 2010-2022.

RESULTS

In the whole cohort of 376 patients with acute BAO treated with recanalization therapy, 245 (65.2%) received only IVT. In the IVT-only cohort, most patients had moderate-to-severe clinical presentation (median NIH Stroke Scale 18) but no extensive early ischemic changes in the posterior circulation on admission. Half of them had onset-to-treatment time over 6 hours. 46.5% of the IVT-treated patients achieved 3-month favorable functional outcome, whereas mortality was 35.9%. sICH occurred in 11.1%. In a multivariable analysis, younger age, milder symptom severity, and less baseline ischemic changes predicted favorable functional outcome. In the 2010-2022 cohort, when compared with patients treated with EVT+/-IVT (n = 121), the IVT-only cohort (n = 122) had higher odds for favorable functional outcome (IVT 58.2% vs EVT 43.0% (aOR 2.82 [95% CI 1.31-6.05]).

DISCUSSION

IVT alone produced outcomes comparable with those in recent trials of endovascular BAO recanalization. Furthermore, in head-to-head comparison in our cohort, the IVT-only approach was more often associated with favorable outcome than EVT+/-IVT. Thus, it should not be overlooked as the first-line recanalization therapy in acute BAO, even in longer time windows.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that tPA is as effective as thrombectomy for basilar artery thrombosis.

Posterior circulation collaterals as predictors of outcome in basilar artery occlusion: a sub-analysis of the BASICS randomized trial

Introduction and purpose

Basilar artery occlusion (BAO) is still one of the most devastating neurological conditions associated with high morbidity and mortality. In the present study, we aimed to assess the role of posterior circulation collaterals as predictors of outcome in the BASICS trial and to compare two grading systems (BATMAN score and PC-CS) in terms of prognostic value.

Methods

We performed a sub-analysis of the BASICS trial. Baseline clinical and imaging variables were analyzed. For the imaging analysis, baseline CT and CTA were analyzed by a central core lab. Only those patients with good or moderate quality of baseline CTA and with confirmed BAO were included. Multivariable binary logistic regression analysis was used to test the independent association of clinical and imaging characteristics with a favorable outcome at 3 months (defined as a modified Rankin Score of ≤3). ROC curve analysis was used to assess and compare accuracy between the two collateral grading systems.

Results

The mean age was 67.0 (±12.5) years, 196 (65.3%) patients were males and the median NIHSS was 21.5 (IQR 11-35). Median NCCT pc-ASPECTS was 10 (IQR10-10) and median collateral scores for BATMAN and PC-CS were 8 (IQR 7-9) and 7 (IQR 6-8) respectively. Collateral scores were associated with favorable outcome at 3 months for both BATMAN and PC-CS but only with a modest accuracy on ROC curve analysis (AUC 0.62, 95% CI [0.55-0.69] and 0.67, 95% CI [0.60-0.74] respectively). Age (OR 0.97, 95% CI [0.95-1.00]), NIHSS (OR 0.91, 95% CI [0.89-0.94]) and collateral score (PC-CS - OR 1.2495% CI [1.02-1.51]) were independently associated with clinical outcome.

Conclusion

The two collateral grading systems presented modest prognostic accuracy. Only the PC-CS was independently associated with a favorable outcome at 3 months.

What Is the Evidence for Endovascular Thrombectomy in Posterior Circulation Stroke?

Posterior circulation infarcts comprise approximately 25% of ischemic strokes but are less often treated with recanalization therapy and have longer treatment delays compared with anterior circulation strokes. Among posterior circulation strokes, basilar artery occlusion is associated with the most severe deficits and the worst prognosis. Endovascular thrombectomy is a standard of care for patients with anterior circulation large vessel occlusion, but not until recently were the first randomized controlled trials on endovascular thrombectomy in basilar artery occlusion published. Two of the trials were neutral, whereas two others showed better functional outcome after thrombectomy up to 24 hours of symptom onset compared with best medical treatment, which in most cases had low rates of intravenous thrombolysis. According to observational data, thrombectomy seems to be safe also in isolated posterior cerebral artery occlusions and might be an option for selected patients, even if its outcome benefit is yet to be demonstrated.

Endovascular thrombectomy for basilar artery occlusion stroke: Analysis of the German Stroke Registry-Endovascular Treatment

BACKGROUND AND PURPOSE

Acute ischemic stroke due to basilar artery occlusion (BAO) causes the most severe strokes and has a poor prognosis. Data regarding efficacy of endovascular thrombectomy in BAO are sparse. Therefore, in this study, we performed an analysis of the therapy of patients with BAO in routine clinical practice.

METHODS

Patients enrolled between June 2015 and December 2019 in the German Stroke Registry-Endovascular Treatment (GSR-ET) were analyzed. Primary outcomes were successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score of 2b-3), substantial neurological improvement (≥8-point National Institute of Health Stroke Scale [NIHSS] score reduction from admission to discharge or NIHSS score at discharge ≤1), and good functional outcome at 3 months (modified Rankin Scale [mRS] score of 0-2).

RESULTS

Out of 6635 GSR-ET patients, 640 (9.6%) patients (age 72.2 ± 13.3, 43.3% female) experienced BAO (median [interquartile range] NIHSS score 17 [8, 27]). Successful reperfusion was achieved in 88.4%. Substantial neurological improvement at discharge was reached by 45.5%. At 3-month follow-up, good clinical outcome was observed in 31.1% of patients and the mortality rate was 39.2%. Analysis of mTICI3 versus mTICI2b groups showed considerable better outcome in those with mTICI3 (38.9% vs. 24.4%; p = 0.005). The strongest predictors of good functional outcome were intravenous thrombolysis (IVT) treatment (odds ratio [OR] 3.04, 95% confidence interval [CI] 1.76-5.23) and successful reperfusion (OR 4.92, 95% CI 1.15-21.11), while the effect of time between symptom onset and reperfusion seemed to be small.

CONCLUSIONS

Acute reperfusion strategies in BAO are common in daily practice and can achieve good rates of successful reperfusion, neurological improvement and good functional outcome. Our data suggest that, in addition to IVT treatment, successful and, in particular, complete reperfusion (mTICI3) strongly predicts good outcome, while time from symptom onset seemed to have a lower impact.

Hyperdense Artery Sign and Clinical Outcomes After Endovascular Treatment in Acute Basilar Artery Occlusion

Background

This study aimed to investigate the association between the hyperdense basilar artery sign (HBAS) on non-enhanced computed tomography (CT) and clinical outcomes in patients with acute basilar artery occlusion (BAO) who underwent endovascular treatment (EVT).

Methods

Eligible patients who underwent EVT due to acute BAO between January 2014 and May 2019 were divided into two groups based on HBAS. HBAS was assessed by two neuroradiologists using five grades on nonenhanced CT. The primary outcome was a favorable functional outcome (defined as a modified Rankin Scale [mRS] of 0-3) at 90 days. Secondary outcomes included successful recanalization and mortality within 90 days.

Results

Among 829 patients with BAO as assessed with CT angiography, magnetic resonance angiography, or digital subtraction angiography, 643 patients were treated with EVT. Of these, 51.32% (330/643) had HBAS. Patients with HBAS were older and had more severe neurological deficits and a higher frequency of atrial fibrillation than those without HBAS. There was no significant difference in favorable outcome (adjusted odds ratio [aOR]: 1.354, 95% confidence interval [CI]: 0.906-2.024; p = 0.14), successful recanalization (aOR: 0.926, 95% CI: 0.616--1.393; p = 0.71), and mortality (aOR: 1.193, 95% CI: 0.839-1.695; p = 0.33) between patients with or without HBAS. Subgroup analysis showed that the HBAS predicted a favorable outcome in patients aged <60 years (aOR: 2.574, 95% CI: 1.234-5.368; p = 0.01) and patients with vertebral artery-V4 segment occlusion (aOR: 3.738, 95% CI: 1.212-11.530; p = 0.02). In patients with HBAS, the baseline National Institutes of Health Stroke Scale (NIHSS) score, posterior circulation-Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS), and stent retriever were associated with successful recanalization.

Conclusions

Our study did not find a significant association between HBAS and favorable outcomes and successful recanalization in patients with BAO who underwent EVT. Moreover, large prospective studies are warranted to further investigate this relationship.

Focal brainstem infarction in the adult rat

Animal models are required to study the pathogenesis of brainstem ischemia and to develop new therapeutic approaches to promote functional recovery after ischemia in humans. Few models of brainstem ischemia are available, and they show great variability or cause early lethality. New, reliable animal models are therefore needed. By selectively ligating four points of the lower basilar artery, we developed a new focal basilar artery occlusion model that causes a localized brainstem ischemic lesion in female Sprague-Dawley rats. Analysis of ischemic lesion volume and neurological deficits over a period of 28 d showed that the rats present symptoms specific to this type of stroke while the ischemic lesion remains relatively unchanged over time. This procedure allows higher survival rates and extended observation periods compared with other models of brainstem ischemia. The procedure takes ~40 min, can be performed by researchers with basic surgical skills and does not require specialized surgical equipment. This protocol is highly reliable and will be useful to evaluate new therapeutic approaches to promote functional recovery in patients with brainstem ischemia.

Basilar Artery Occlusion and Emerging Treatments

Basilar artery occlusion is a relatively uncommon but neurologically devastating condition. If revascularization is not achieved, the potential for death and disability is substantial. During the last several years, there have been positive endovascular stroke trials for the treatment of large vessel occlusion; however, all of them excluded patients with basilar artery occlusion. The current treatment of basilar artery occlusion is still founded on small observational studies or meta-analyses. As case selection for revascularization and treatment protocols often vary widely across institutions, sample sizes remain limited. In this article, we aim to review some of the larger observational studies in stroke due to basilar artery occlusion, considering potential treatment strategies and resultant outcomes.

Early Neurological Deterioration Despite Recanalization in Basilar Artery Occlusion Treated by Endovascular Therapy

Background: We aim to identify the risk factors of early neurological deterioration (END) despite successful recanalization and explore the association of END with 90-day outcomes in acute basilar artery occlusion (BAO) treated by endovascular therapy (EVT).

Methods: A prospectively registered consecutive cohort of BAO patients with successful recanalization by EVT in a tertiary stroke center during a 6-year period was reviewed. END was defined as an National Institutes of Health Stroke Scale (NIHSS) score increase ≥4 points, or death, from baseline to 24 h after EVT. Multivariate logistic regression analysis was used to identify the risk factors of END. The 90-day outcomes between END and non-END groups were compared by Pearson's χ² test.

Results: END was observed in 21 of 148 patients included in this study. Multivariate logistic regression analysis showed that patients with progressive or fluctuating symptoms had a higher risk of END than those with symptoms of acute attack (OR 5.52, 95% CI 1.73–17.63), and NIHSS score and puncture-to-recanalization time (PTR), as continuous variables, were also significantly associated with END. Using a generalized additive model with spline smoothing function, we observed a linear relationship between PTR (increased by 1 h) and END (OR 2.57, 95% CI 1.45–4.57), and a non-linear relationship between NIHSS score and END. Only when the NIHSS score was ≥23 points was it related to END (OR 0.7, 95% CI 0.6–0.9). In addition, patients with END had a lower proportion of 90-day favorable outcome (19.0 vs. 59.1%, p < 0.01) and higher mortality (33.3 vs. 13.4%, p = 0.048) than those with non-END.

Conclusion: Mode of stroke onset, NIHSS score, and PTR may help to identify BAO patients with a higher risk of END after EVT. Moreover, END may affect the 90-day outcomes of these patients.

Clinical outcomes of mechanical thrombectomy following intravenous administration of recombinant tissue-type plasminogen activator for basilar artery occlusion

OBJECTIVE

Mechanical thrombectomy (MT) following intravenous administration of recombinant tissue-type plasminogen activator (IV-rt-PA) is considered an effective treatment for the occlusion of the internal carotid artery or the M1 segment of the middle cerebral artery. However, its efficacy in treating basilar artery (BA) occlusion is still unclear. In order to evaluate the efficacy of MT in treating BA occlusion, we aimed to analyzed the clinical outcomes of those patients who had undergone MT following IV-rt-PA administration.

PATIENTS AND METHODS

We retrospectively analyzed the clinical outcomes of 11 patients with BA occlusion who had undergone MT following IV-rt-PA administration between January 1, 2015, and March 31, 2019.

RESULTS

The patients consisted of 8 men and 3 women. The mean (±standard deviation) age was 73 ± 9.4 years. Stroke subtypes were found to be atherothrombosis in 2 patients, cardiogenic embolism in 6, arterial dissection in 1, and an unknown cause in 2. The median pretreatment scores were 9 on the Glasgow Coma Scale (GCS) and 25 on the National Institutes of Health Stroke Scale. The time elapsed from onset of the stroke to reperfusion was 281 min. Successful reperfusion, characterized by a modified Thrombolysis in Cerebral Infarction grade ≥ 2b, was achieved in all patients. The 3-month outcomes were good [modified Rankin Scale (mRS) 0-2] in 5 patients and poor (mRS 3-6) in 6 patients. The pretreatment median GCS scores were significantly higher in patients with a good outcome compared to that in those with a poor outcome with scores of 11 and 7.5, respectively (P =  0.044). The receiver operating characteristic (ROC) curve analysis showed that the optimal cut-off score on the GCS was 9.5 [area under the curve (AUC), 0.867; sensitivity, 0.8; specificity, 1.0]. Complications occurred in 1 patient with arterial dissection who had developed a subarachnoid hemorrhage and later died.

CONCLUSION

The results of the present study suggests that the pretreatment GCS score might affect the clinical outcomes in patients with BA occlusion who underwent MT following IV-rt-PA therapy.

Intravenous infusion of mesenchymal stem cells for protection against brainstem infarction in a persistent basilar artery occlusion model in the adult rat

OBJECTIVE

Morbidity and mortality in patients with posterior circulation stroke remains an issue despite advances in acute stroke therapies. The intravenous infusion of mesenchymal stem cells (MSCs) elicits therapeutic efficacy in experimental supratentorial stroke models. However, since there are few reliable animal models of ischemia in the posterior circulation, the therapeutic approach with intravenous MSC infusion has not been tested. The objective of this study was to test the hypothesis that intravenously infused MSCs provide functional recovery in a newly developed model of brainstem infarction in rats.

METHODS

Basilar artery (BA) occlusion (BAO) was established in rats by selectively ligating 4 points of the proximal BA with 10-0 nylon monofilament suture. The intravenous infusion of MSCs was performed 1 day after BAO induction. MRI and histological examinations were performed to assess ischemic lesion volume, while multiple behavioral tests were performed to evaluate functional recovery.

RESULTS

The MSC-treated group exhibited a greater reduction in ischemic lesion volume, while behavioral testing indicated that the MSC-infused group had greater improvement than the vehicle group 28 days after the MSC infusion. Accumulated infused MSCs were observed in the ischemic brainstem lesion.

CONCLUSIONS

Infused MSCs may provide neuroprotection to facilitate functional outcomes and reduce ischemic lesion volume as evaluated in a newly developed rat model of persistent BAO.

Predictors of Outcome After Endovascular Thrombectomy in Acute Basilar Artery Occlusion and the 6hr Time Window to Recanalization

Background and Purpose: Decision algorithms for large vessel occlusions in the anterior circulation remain unconfirmed for acute basilar artery occlusion (aBAO). The aim of this study was to investigate procedural parameters, patient characteristics, functional outcome, and survival in dependency of the time window to recanalization from symptom onset. Furthermore predictors of outcome were identified.

Materials and Methods: Retrospectively 231 patients with aBAO treated with endovascular treatment (EVT) between November 2008 and February 2019 were identified in a prospectively maintained single center stroke database. Baseline characteristics such as age, cardiovascular risk factors, NIHSS at admission, pre-interventional PC-ASPECTS, periprocedural parameters such as time to recanalization, duration of treatment, extent of reperfusion, collateral status, and occlusion patterns, as well as post-interventional 24 h NIHSS and post-interventional ICH were evaluated. Target variables were mRS at 90 days and mortality over 90 days.

Results: Good outcome (mRS 0–2) was attained in 29.5% (n = 68) of patients, overall mortality was 36.8% (n = 85). In mulitivariate analyses patients with time to reperfusion beyond 6 h had a more than half fold decreased chance of good outcome [OR 0.47 95% CI (0.23–0.95) p < 0.05]. The odds for good outcome were reduced by almost 2/3 if post-interventional imaging revealed intracerebral hemorrhage [OR 0.28 95% CI (0.08–0.98)]. Unfavorable outcome was noted in 100% (n = 14) of patients with symptomatic ICH. Risk for death was reduced by more than 80% if collaterals were present [0.16 95% CI (0.03–0.87)] and if recanalization was successful (TICI 2b-3) [OR 0.19 95% CI (0.05–0.78)]. The odds for survival were 5-fold higher in patients with no post-interventional hemorrhages present [OR 5.35 95% CI (2.2–1.58)].

Conclusion: This study might contribute to explaining the ambiguous findings regarding the validity of the 6 h time window in aBAO, suggesting that collateral status impacts the odds of survival in the time window to recanalization beyond 6 h. In our study recanalization within 6 h from symptom onset was associated with good outcome. Successful recanalization (TICI 2b-3a) was necessary for good outcome and survival, post-interventional ICH was highly associated with unfavorable outcome. This might ease the decision making for EVT.

Therapy for acute basilar artery occlusion: a systematic review and meta-analysis

Purpose: This study aims to analyse the efficacy of different treatment methods for acute basilar artery occlusion, with an emphasis placed on evaluating the latest treatment methods. Method:  A systematic review and meta-analysis was performed to analyse the current data on the therapies available for treating acute basilar artery occlusion. Results: A total of 102 articles were included. The weighted pooled rate of mortality was 43.16% (95% CI 38.35-48.03%) in the intravenous thrombolysis group, 45.56% (95% CI 39.88-51.28) in the intra-arterial thrombolysis group, and 31.40% (95% CI 28.31-34.56%) for the endovascular thrombectomy group. The weighted pooled rate of Modified Ranking Score (mRS) 0-2 at 3 months was 31.40 (95% CI 28.31-34.56%) in the IVT group, 28.29% (95% CI 23.16-33.69%) in the IAT group, and 35.22% (95% CI 32.39-38.09%) for the EVT group. Meta-analyses were also done for the secondary outcomes of recanalization and symptomatic haemorrhage. There was no difference between stent retriever and thrombo-aspiration thrombectomy on subgroup analysis in both clinical outcome and safety profile. Limitations: The included studies were observational in nature. There was significant heterogeneity in some of the outcomes. Conclusions:  Superior outcomes and better recanalization rates for acute basilar occlusion were seen with patients managed with endovascular thrombectomy when compared with either intravenous and/or intraarterial thrombolysis. No superiority of stent-retrievers over thrombo-aspiration thrombectomy was seen.

Vertebral Artery Patency and Thrombectomy in Basilar Artery Occlusions

Background and Purpose—

Factors influencing recanalization success in basilar artery occlusions are largely unknown. Preliminary evidence has suggested that flow arrest in the vertebral artery contralateral to the catheter bearing vertebral artery may facilitate recanalization. The aim of this analysis was to assess the impact of anatomic variations and flow conditions on recanalization success in basilar artery occlusion treated with mechanical thrombectomy.

Methods—

Consecutive basilar artery occlusions treated with second-generation thrombectomy devices at a single-center were retrospectively analyzed. Baseline patients’ characteristics, occlusion length, collateral circulation, underlying stenosis, incomplete occlusions, and patency of the vertebral arteries were analyzed with regards to recanalization success. Aplastic or hypoplastic vertebral artery contralateral to the catheter position was defined as contralateral low flow condition. Logistic regression analysis was used to examine the association between anatomic variations and flow conditions in relation to complete recanalization and the modified Rankin Scale score while controlling for several potentially confounding variables. Clinical impact was evaluated using the modified Rankin Scale score of ≤3.

Results—

One hundred fifteen patients were included (mean age 71.5±12.8, m:f=2:1, median National Institutes of Health Stroke Scale =15, interquartile range =10–22). Complete recanalization was more often observed in patients with contralateral low flow conditions (80.6% versus 50.0%), which remained an independent predictor of complete recanalization in multivariable analysis (adjusted odds ratio, 5.81; 95% CI, 1.97–17.19). Patients with complete posterior recanalization had lower in-hospital mortality (16.4% versus 41.7%) and more often achieved modified Rankin Scale score of ≤3 (49.4% versus 8.3%), even after adjusting for potential confounders (adjusted odds ratio, 15.93; 95% CI, 1.42–179.00).

Conclusions—

Contralateral low flow condition (vertebral artery aplasia or hypoplasia) seems to be an independent factor for fewer distal emboli and complete recanalization in basilar artery occlusion patients treated by modern endovascular devices. Complete recanalization reflecting the absence of peri-interventional clot fragmentation brings clear clinical benefit. Further studies are warranted to evaluate the need for contralateral flow modulation or ipsilateral balloon guide catheter during posterior circulation thrombectomy in patients with bilaterally patent vertebral arteries.

Impact of smoking on stroke outcome after endovascular treatment

Background

Recent studies suggest a paradoxical association between smoking status and clinical outcome after intravenous thrombolysis (IVT). Little is known about relationship between smoking and stroke outcome after endovascular treatment (EVT).

Methods

We analyzed data of all stroke patients treated with EVT at the tertiary stroke centre of Berne between January 2005 and December 2015. Using uni- and multivariate modeling, we assessed whether smoking was independently associated with excellent clinical outcome (modified Rankin Scale (mRS) 0–1) and mortality at 3 months. In addition, we also measured the occurrence of symptomatic intracranial hemorrhage (sICH) and recanalization.

Results

Of 935 patients, 204 (21.8%) were smokers. They were younger (60.5 vs. 70.1 years of age, p<0.001), more often male (60.8% vs. 52.5%, p = 0.036), had less often from hypertension (56.4% vs. 69.6%, p<0.001) and were less often treated with antithrombotics (35.3% vs. 47.7%, p = 0.004) as compared to nonsmokers. In univariate analyses, smokers had higher rates of excellent clinical outcome (39.1% vs. 23.1%, p<0.001) and arterial recanalization (85.6% vs. 79.4%, p = 0.048), whereas mortality was lower (15.6% vs. 25%, p = 0.006) and frequency of sICH similar (4.4% vs. 4.1%, p = 0.86). After correcting for confounders, smoking still independently predicted excellent clinical outcome (OR 1.758, 95% CI 1.206–2.562; p<0.001).

Conclusion

Smoking in stroke patients may be a predictor of excellent clinical outcome after EVT. However, these data must not be misinterpreted as beneficial effect of smoking due to the observational study design. In view of deleterious effects of cigarette smoking on cardiovascular health, cessation of smoking should still be strongly recommended for stroke prevention.

Impact of stroke mechanism in acute basilar occlusion with reperfusion therapy

Objective

We aimed to evaluate the impact of underlying mechanism of basilar artery (BA) occlusion on the outcomes after endovascular therapy (EVT) for reperfusion and the outcome factors associated with each mechanism, and to identify radiologic parameters enabling to distinguish the underlying mechanism.

Methods

From a registry database, 194 consecutive patients with acute BA occlusion who underwent EVT were analyzed. Stroke mechanism, classified into in situ atherosclerotic thrombosis (ISAT) and embolism, clot sign location profiles in pre‐angiography magnetic resonance image (MRI), parameters of angiography and EVT, and reperfusion were assessed. Poor outcome was defined as a modified Rankin‐Scale score at 90 days of 3–6.

Results

The mean age was 68.8±11.8 years (range 21–92 years) and seventy‐eight (40.2%) were female patients. 102 (52.6%) patients were classified into an embolism mechanism and 92 (47.4%) into an ISAT mechanism. Overall, ISAT mechanism compared with embolism was significantly associated with poor outcomes (P = 0.002), along with the NIHSS scores, reperfusion status, and collateral status. In the embolism group, reperfusion (P = 0.001), NIHSS scores (P < 0.001), and onset‐to‐treatment time (P = 0.030) were significant outcome factors. However, in the ISAT group, baseline collateral status (P = 0.001) and NIHSS scores (P < 0.001) were significant outcome factors. A clot sign at the distal BA segment on pre‐angiography MRI was strongly associated with embolism mechanism (P < 0.001).

Interpretation

Stroke mechanism has a major influence on outcomes, and outcome predictors differ according to the underlying mechanism in acute BA occlusion with EVT. Clot sign profile on pre‐angiography MRI might be useful to determine the underlying mechanism.

Effectiveness and Safety of Mechanical Thrombectomy with Stent Retrievers in Basilar Artery Occlusion: Comparison with Anterior Circulation Occlusions

Objective

Acute basilar artery occlusion (BAO) is associated with severe neurological dysfunction and high mortality rates. The benefits of mechanical thrombectomy in BAO have not been explored in recent clinical trials. Therefore, we analyzed outcomes of stent retriever mechanical thrombectomy for BAO, and compared with anterior circulation occlusions (ACO).

Methods

In total, 161 consecutive patients (24 BAO, 137 ACO) who underwent mechanical thrombectomy with the stent retriever between January 2013 and August 2016 enrolled in our study. All patients underwent clinical assessment with the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS). Radiological results were used to evaluate thrombolysis in cerebral infarction (TICI) scores and successful recanalization was defined by TICI 2b or 3.

Results

Mean NIHSS scores at 24 hours and 30 days were significantly higher in the BAO group than the ACO group (p=0.021, p=0.001). mRS at 90 days was significantly higher in the BAO group (4.2) compared with the ACO group (3.0) (p=0.003). The BAO group (2.0) performed fewer stent retriever passages than the ACO group (2.7) (p=0.049). There were no significant differences between the two groups in terms of complications, but the BAO patients experienced a higher mortality (16.6%) rate than ACO patients (5.8%) (p=0.001). In subgroup analysis of BAO, patients with short procedure times achieved successful recanalization (p=0.001) and successfully recanalized patients exhibited more favorable mRS at 90 days (p=0.027).

Conclusion

In our study, mechanical thrombectomy of BAO patients showed worse clinical outcome and higher mortality rate than ACO patients. However, mechanical thrombectomy with a stent retriever in BAO is an effective treatment, because successfully recanalized patients showed good clinical outcome in BAO patients.

Optimizing the Definitions of Stroke, Transient Ischemic Attack, and Infarction for Research and Application in Clinical Practice

BACKGROUND AND PURPOSE

Until now, stroke and transient ischemic attack (TIA) have been clinically based terms which describe the presence and duration of characteristic neurological deficits attributable to intrinsic disorders of particular arteries supplying the brain, retina, or (sometimes) the spinal cord. Further, infarction has been pathologically defined as death of neural tissue due to reduced blood supply. Recently, it has been proposed we shift to definitions of stroke and TIA determined by neuroimaging results alone and that neuroimaging findings be equated with infarction.

METHODS

We examined the scientific validity and clinical implications of these proposals using the existing published literature and our own experience in research and clinical practice.

RESULTS

We found that the proposals to change to imaging-dominant definitions, as published, are ambiguous and inconsistent. Therefore, they cannot provide the standardization required in research or its application in clinical practice. Further, we found that the proposals are scientifically incorrect because neuroimaging findings do not always correlate with the clinical status or the presence of infarction. In addition, we found that attempts to use the proposals are disrupting research, are otherwise clinically unhelpful and do not solve the problems they were proposed to solve.

CONCLUSION

We advise that the proposals must not be accepted. In particular, we explain why the clinical focus of the definitions of stroke and TIA should be retained with continued sub-classification of these syndromes depending neuroimaging results (with or without other information) and that infarction should remain a pathological term. We outline ways the established clinically based definitions of stroke and TIA, and use of them, may be improved to encourage better patient outcomes in the modern era.

Neuroimaging Predictors of Clinical Outcome in Acute Basilar Artery Occlusion

Certain early neuroimaging findings are independent predictors of clinical outcome in acute basilar artery occlusion. These imaging findings may serve as important baseline imaging characteristics as well as subgroups in future randomized controlled trials. The purpose of this review is to review and compare early neuroimaging findings seen on non-invasive cranial imaging that predict clinical outcome in acute basilar artery occlusion.

Clot length predicts recanalisation but not outcome after basilar artery occlusion

Introduction

The aim of our study was to evaluate the effect of clot length on both recanalisation and outcome in acute basilar artery occlusion (BAO).

Patients and methods

One hundred forty-nine patients with an acute basilar artery occlusion from the Basilar Artery International Cooperation Study (BASICS) were included. Clot length was assessed on computed tomographic angiography. Thrombus length was divided in tertiles and was related to recanalisation and outcome at 1 month, with Poisson regression. Modified Rankin scale scores of 4 or 5, or death were considered poor outcomes. Additionally, clot length was analysed as a continuous variable.

Results

Forty-nine patients (33%) had a short (4-11 mm), 50 (34%) an intermediate (12-22 mm), and 50 (34%) a long clot (≥23 mm). Multivariable analyses showed a significantly lower probability of recanalisation but no statistically significant difference in poor outcome for patients with a long clot compared with patients with a short clot (RR 0.64, 95% CI: 0.42-0.98 and RR 1.10, 95% CI: 0.88-1.37, respectively). No statistically significant differences were found for patients with an intermediate clot length compared with patients with a short clot length (RR 0.97, 95% CI: 0.75-1.25 and RR 1.11, 95% CI: 0.88-1.40, respectively). Analyses of clot length as a continuous variable showed a 10% reduction in chance of recanalisation and a 2% increase in risk of poor outcome with every centimeter increase in clot length (RR 0.90, 95% CI: 0.78-1.04 and RR 1.02, 95% CI: 0.98-1.05, respectively).

Conclusions

Clot length predicted recanalisation but not outcome at 1 month in patients with a BAO. We found 2% more poor outcome and 10% less recanalisation with every centimeter increase in clot length.

CT-angiography source images indicate less fatal outcome despite coma of patients in the Basilar Artery International Cooperation Study

Background

Coma is associated with poor outcome in patients with basilar artery occlusion.

Aims

We sought to assess whether the posterior circulation Acute Stroke Prognosis Early CT Score and the Pons-Midbrain Index applied to CT angiography source images predict the outcome of comatose patients in the Basilar Artery International Cooperation Study.

Methods

Basilar Artery International Cooperation Study was a prospective, observational registry of patients with acute basilar artery occlusion with 48 recruiting centers worldwide. We applied posterior circulation Acute Stroke Prognosis Early CT Score and Pons-Midbrain Index to CT angiography source images of Basilar Artery International Cooperation Study patients who presented with coma. We calculated adjusted risk ratios to assess the association of dichotomized posterior circulation Acute Stroke Prognosis Early CT Score (≥8 vs. <8) and Pons-Midbrain Index (<3 vs. ≥3) with mortality and favourable outcome (modified Rankin Scale score 0–3) at one month.

Results

Of 619 patients in the Basilar Artery International Cooperation Study registry, CT angiography source images were available for review in 158 patients. Among these, 78 patients (49%) presented with coma. Compared to non-comatose patients, comatose patients were more likely to die (risk ratios 2.34; CI 95% 1.56–3.52) and less likely to have a favourable outcome (risk ratios 0.44; CI 95% 0.24–0.80). Among comatose patients, a Pons-Midbrain Index < 3 was related to reduced mortality (adjusted RR 0.66; 95% CI 0.46–0.96), but not to favourable outcome (adjusted RR 1.19; 95% CI 0.39–3.62). Posterior circulation Acute Stroke Prognosis Early CT Score dichotomized at ≥ 8 vs. <8 was not significantly associated with death (adjusted RR 0.70; 95% CI 0.46–1.05).

Conclusion

In comatose patients with basilar artery occlusion, the extent of brainstem ischemia appears to be related to mortality but not to favourable outcome.

Collateral flow predicts outcome after basilar artery occlusion: The posterior circulation collateral score

Background and Aim

Our aim was to assess the prognostic value of a semiquantitative computed tomography angiography-based grading system, for the prediction of outcome in patients with acute basilar artery occlusion, based on the presence of potential collateral pathways on computed tomography angiography: the posterior circulation collateral score (PC-CS).

Methods

One hundred forty-nine patients with acute basilar artery occlusion from the Basilar Artery International Cooperation Study were included. We related poor outcome at one month, defined as a modified Rankin scale score of 4 or 5, or death to collateral flow with Poisson regression. We used a 10 points grading system to quantify the potential for collateral flow in the posterior communicating arteries and the cerebellar arteries. Additionally, the relation between the presence and size of posterior communicating arteries and outcome was analyzed.

Results

Thirty-six patients had poor (PC-CS: 0–3), 59 patients intermediate (PC-CS: 4–5), and 54 patients good (PC-CS: 6–10) collaterals. Multivariable analyses showed a statistically significant lower risk of poor outcome in patients with a good PC-CS than in patients with a poor PC-CS (risk ratio (RR): 0.74, 95% confidence interval (CI): 0.58–0.96), but not for patients with an intermediate PC-CS compared with patients with a poor PC-CS (RR: 0.95, 95% CI: 0.78–1.15). Multivariable analyses showed a statistically significant lower risk of poor outcome for the presence of at least one posterior communicating artery and for larger caliber of posterior communicating arteries (RR: 0.79, 95% CI: 0.66–0.95 and 0.76, 95% CI: 0.61–0.96, respectively).

Conclusions

The PC-CS predicted poor outcome at one month. In a separate analysis, both the absence and smaller caliber of posterior communicating arteries predicted poor outcome.

Implications of limiting mechanical thrombectomy to patients with emergent large vessel occlusion meeting top tier evidence criteria

BACKGROUND

Recent guidelines for endovascular management of emergent large vessel occlusion (ELVO) award top tier evidence to the same selective criteria in recent trials. We aimed to understand how guideline adherence would have impacted treatment numbers and outcomes in a cohort of patients from a comprehensive stroke center.

METHODS

A retrospective observational study was conducted using consecutive emergent endovascular patients. Mechanical thrombectomy (MT) was performed with stent retrievers or large bore clot aspiration catheters. Procedural outcomes were compared between patients meeting, and those failing to meet, top tier evidence criteria.

RESULTS

126 patients receiving MT from January 2012 to June 2015 were included (age 31-89 years, National Institutes of Health Stroke Scale (NIHSS) score 2-38); 62 (49%) patients would have been excluded if top tier criteria were upheld: pretreatment NIHSS score <6 (10%), Alberta Stroke Program Early CT score <6 (6.5%), premorbid modified Rankin Scale (mRS) score ≥2 (27%), M2 occlusion (10%), posterior circulation (32%), symptom to groin puncture >360 min (58%). 26 (42%) subjects had more than one top tier exclusion. Symptomatic intracerebral hemorrhage (sICH) and systemic hemorrhage rates were similar between the groups. 3 month mortality was 45% in those lacking top tier evidence compared with 26% (p=0.044), and 3 month mRS score 0-2 was 33% versus 46%, respectively (NS). After adjusting for potential confounders, top tier treatment was not associated with neurological improvement during hospitalization (β -8.2; 95% CI -24.6 to -8.2; p=0.321), 3 month mortality (OR=0.38; 95% CI 0.08 to 1.41), or 3 month favorable mRS (OR=0.97; 95% CI 0.28 to 3.35).

CONCLUSIONS

Our study showed that with strict adherence to top tier evidence criteria, half of patients may not be considered for MT. Our data indicate no increased risk of sICH and a potentially higher mortality that is largely due to treatment of patients with basilar occlusions and those treated at an extended time window. Despite this, good functional recovery is possible, and consideration of MT in patients not meeting top tier evidence criteria may be warranted.

Mechanical thrombectomy in acute basilar artery occlusion: A safety and efficacy single centre study

OBJECTIVES

The objective of this study was to add more evidence about the efficacy and safety of mechanical thrombectomy in patients with basilar artery occlusion and secondarily to identify prognostic factors.

METHODS

Twenty-two consecutive patients (mean age 60.5 years, 15 men) with basilar artery occlusion treated with mechanical thrombectomy were included. Clinical, procedure and radiological data were collected. Primary outcomes were the modified Rankin scale score with a good outcome defined by a modified Rankin scale score of 0-2 and mortality rate at three months.

RESULTS

The median National Institutes of Health stroke scale at admission was 24 (interquartile range 11.5-31.25). Twelve patients (54.5%) required tracheal intubation due to a decreased level of consciousness. Successful recanalisation (modified treatment in cerebral ischaemia scale 2b-3) was achieved in 20 patients (90.9%). A favourable clinical outcome (modified Rankin scale score 0-2) was observed in nine patients (40.9%) and the overall mortality rate was 40.9% (nine patients). Haemorrhagic events were observed in three patients (13.63%). A decreased level of consciousness requiring intubation in the acute setting was more frequent in patients with poor outcomes (84.6%) than in patients with favourable outcomes (11.1%), and in patients who died (100%) compared with those who survived (23.1%), with a statistically significant difference (P = 0.002 and P = 0.001, respectively).

CONCLUSION

Mechanical thrombectomy is feasible and effective in patients with acute basilar artery occlusion. A decreased level of consciousness requiring tracheal intubation seems to be a prognostic factor and is associated with a poor clinical outcome and higher mortality rate. These initial results must be confirmed by further prospective studies with a larger number of patients.

Is there association between hyperdense middle cerebral artery sign on CT scan and time from stroke onset within the first 24-hours?

Background

The hyperdense artery sign (HAS) on CT brain scan is an assumed radiological marker of acute intra-arterial thrombotic occlusion. However, the relationship between HAS between time of stroke onset has not been adequately investigated, leading to uncertainty regarding its validity as a marker of acute ischaemia. We attempted to determine if the presence of the hyperdense artery sign is associated with time from stroke onset.

Methods

Retrospective cross-sectional study conducted in a tertiary referral centre. Consecutive patients with acute ischaemic stroke and confirmed middle cerebral arterial occlusion on initial CT angiogram from 2007–2011 were included. Visual estimation and manual measurement of Hounsfield units of affected and corresponding non-affected artery on non-contrast CT was completed and mean density was calculated from four separate readings. Primary outome measures were Time from stroke onset and HAS on both visual estimation and the ratio of mean value in Hounsfield Units (HU) of affected to non-affected artery.

Results

One hundred and fifty-four subjects with confirmed arterial occlusion on CT Angiogram were included in the study. There were no significant differences in age distribution or vascular risk factor presence between subjects with or without HAS. Subjects with HAS were less likely to be male (50.9 % vs 70.8 %, p = 0.02).) HAS was found in 106 (68.8 %) of all subjects. Median NIHSS score at presentation was significantly higher in the HAS group (17 vs 12, p = 0.02). No statistically significant association between HAS and stroke onset time or density ratio between affected and non-affected artery was detected overall within either the first 24-h or on subgroup analysis of those in the first 4.5-h. A small subgroup of three patients with stroke onset greater than 24-h all had absent HAS.

Conclusions

No evidence of a correlation between time of stroke onset and presence of a HAS within the first 24-h post acute ischaemic stroke was identified. The HAS was associated with a higher NIHSS score at presentation.

Forced arterial suction thrombectomy with the penumbra reperfusion catheter in acute basilar artery occlusion: a retrospective comparison study in 2 Korean university hospitals

BACKGROUND AND PURPOSE

A performance of forced arterial suction thrombectomy was not reported for the treatment of acute basilar artery occlusion. This study compared revascularization performance between intra-arterial fibrinolytic treatment and forced arterial suction thrombectomy with a Penumbra reperfusion catheter in patients with acute basilar artery occlusion.

MATERIALS AND METHODS

Fifty-seven patients with acute basilar artery occlusion were treated with intra-arterial fibrinolysis (n = 25) or forced arterial suction thrombectomy (n = 32). Baseline characteristics, successful revascularization rate, and clinical outcomes were compared between the groups.

RESULTS

Baseline characteristics, the frequency of patients receiving intravenous recombinant tissue plasminogen activator, and mean time interval between symptom onset and femoral puncture did not differ between groups. The forced arterial suction thrombectomy group had a shorter procedure duration (75.5 minutes versus 113.3 minutes, P = .016) and higher successful revascularization rate (88% versus 60%, P = .017) than the fibrinolysis group. Fair outcome, indicated by a modified Rankin Scale 0-3, at 3 months was achieved in 34% of patients undergoing forced arterial suction thrombectomy and 8% of patients undergoing fibrinolysis (P = .019), and the mortality rate was significantly higher in the fibrinolysis group (25% versus 68%, P = .001). Multiple logistic regression analysis identified the forced arterial suction thrombectomy method as an independent predictor of fair outcome with adjustment for age, sex, initial NIHSS score, and the use of intravenous recombinant tissue plasminogen activator (odds ratio, 7.768; 95% CI, 1.246-48.416; P = .028).

CONCLUSIONS

In acute basilar artery occlusion, forced arterial suction thrombectomy demonstrated a higher revascularization rate and improved clinical outcome compared with traditional intra-arterial fibrinolysis. Further clinical trials with the newer Penumbra catheter are warranted.

Scoring flow restoration in cerebral angiograms after endovascular revascularization in acute ischemic stroke patients

Endovascular revascularization techniques are increasingly used to treat arterial occlusions in patients with acute ischemic stroke. To monitor and communicate treatment results, a valid, reproducible, and clinically relevant, yet easy to use grading scheme of arterial recanalization and tissue reperfusion for digital subtraction angiography is needed. An ideal scoring system would consider the target arterial lesion, the perfusion deficit, and the collateral status before treatment and measure recanalization, reperfusion, early venous shunting, vasospasm, as well as distal embolization after flow restoration. Currently, a variety of different flow restoration scales are in use, including the Thrombolysis in Myocardial Infarction scoring system, the Thrombolysis in Cerebral Infarction score, and the Arterial Occlusive Lesion score, which describe the local recanalization result. These scores are not used homogeneously throughout the literature, are often modified and not fully documented, which make them inept to compare treatment effects across studies. In addition, none of these scores cover all of the above-mentioned aspects, nor are they able to describe satisfactorily all relevant angiographic findings, and data on their reliability and predictive power regarding clinical outcome are sparse. We aimed to review and illustrate the different revascularization scales, discuss their advantages and limitations as well as the available data regarding standardization, reliability testing, and outcome prediction. In addition, we give examples for the use of the scales and show potential pitfalls.

Intravenous thrombolysis of basilar artery occlusion: thrombus length versus recanalization success

BACKGROUND AND PURPOSE

In middle cerebral artery occlusion, probability of recanalization after intravenous tissue-type plasminogen activator thrombolysis (IVT) was reported to drop <1% for thrombi exceeding 8 mm. We aimed to evaluate the effect of thrombus length and location on success of recanalization after IVT in basilar artery occlusion.

METHODS

We evaluated 164 consecutive patients with angiography-proven basilar artery occlusion and available thrombus length. We excluded 24 patients who underwent endovascular treatment. All included patients (n=140) received IVT. Thrombolysis in myocardial infarction 2 to 3 was considered as successful recanalization.

RESULTS

Of the 140 included patients, 37 (26.4%) lacked post-treatment angiography, mostly because of early death. Of the remaining 103 patients, those with recanalization had shorter thrombi (median, 5.5 mm and mean, 9.7 mm) when compared with those with nonrecanalized (median, 15.0 mm and mean, 16.6 mm; P<0.001). Thrombi shorter than 10 mm had 70% to 80% probability of recanalization, whereas 10 to 20 mm, 20 to 30 mm, and >30 mm long thrombi had probabilities of 50% to 70%, 30% to 50%, and 20% to 30%, respectively. Patients with thrombi <10 mm (n=52) and recanalization had more frequently top-of-the basilar (92.5%) and less frequently caudal or midbasilar (7.5%) clot location (P=0.01). In multivariable analysis, thrombus length was independently associated with recanalization (P=0.001). Their relationship remained linear across all lengths.

CONCLUSIONS

Although recanalization of basilar artery occlusion with IVT depends on thrombus length, its probability even in patients with thrombi >30 mm (20%-30%) was substantially higher than minimal recanalization of middle cerebral artery thrombi exceeding 8 mm. There was no threshold length, beyond which basilar artery occlusion recanalization with IVT could ad hoc be deemed hopeless.

Diffusion-weighted imaging score of the brain stem: A predictor of outcome in acute basilar artery occlusion treated with the Solitaire FR device

BACKGROUND AND PURPOSE

The prognosis for ischemic stroke due to acute basilar artery occlusion is very poor: Early recanalization remains the main factor that can improve outcomes. The baseline extent of brain stem ischemic damage can also influence outcomes. We evaluated the validity of an easy-to-use DWI score to predict clinical outcome in patients with acute basilar artery occlusion treated by mechanical thrombectomy.

MATERIALS AND METHODS

We analyzed the baseline clinical and DWI parameters of 31 patients with acute basilar artery occlusion, treated within 24 hours of symptom onset by using a Solitaire FR device. The DWI score of the brain stem was assessed with a 12-point semiquantitative score that separately considered each side of the medulla, pons, and midbrain. Clinical outcome was assessed at 180 days by using the mRS. According to receiver operating characteristic analyses, the cutoff score determined the optimal positive predictive value for outcome. The Spearman rank correlation coefficient assessed the correlation between the DWI brain stem score and baseline characteristics.

RESULTS

Successful recanalization (Thrombolysis in Cerebral Infarction 3-2b) was achieved in 23 patients (74%). A favorable outcome (mRS ≤ 2) was observed in 11 patients (35%). An optimal DWI brain stem score of <3 predicted a favorable outcome. The probability of a very poor outcome (mRS ≥ 5) if the DWI brain stem score was ≥5 reached 80% (positive predictive value) and 100% if this score was ≥6. Interobserver reliability of the DWI brain stem score was excellent, with an intraclass correlation coefficient of 0.97 (95% CI, 0.96-0.99). The DWI brain stem score was significantly associated with baseline tetraplegia (P = .001) and coma (P = .005).

CONCLUSIONS

In patients with acute basilar artery occlusion treated by mechanical thrombectomy, the baseline DWI brain lesion score seems to predict clinical outcome.

Clinical factors are significant predictors of outcome post intra-arterial therapy for acute ischaemic stroke: a review

Intra-arterial therapy (IAT) provides superior recanalisation rates, approaching 80% for the current generation of endovascular devices. Furthermore, IAT may allow for an extended therapeutic window beyond that which is permissible for intravenous thrombolysis. However, the improved recanalisation rates are not matched by concordant clinical outcomes, leading to an invigorated search for predictors of clinical outcome. There is emerging evidence that younger age, mild-moderate stroke, and shorter vessel occlusion time are associated with better clinical outcome after IAT. This review aims to critically appraise current evidence that may inform changes in the selective inclusion of clinical factors in the future design and trial of IAT.

Endovascular neuroradiological treatment of acute ischemic stroke: techniques and results in 350 patients

BACKGROUND AND OBJECTIVES

Randomized trials have demonstrated the benefit of intra-arterial thrombolysis (IAT) for treatment of acute ischemic stroke, if performed within 6 hours of symptom onset.

METHODS

We report our experience with 350 acute stroke patients who were treated with IAT using urokinase at a single center. Predictors of favorable outcome were low National Institute of Health Stroke Scale (NIHSS) at admission (p<0.001), good collaterals (p<0.001) and successful endovascular recanalization (p<0.001). Recanalization rates of more than 75% could be achieved, when additional endovascular techniques such as mechanical fragmentation of the thrombus, thromboaspiration, percutaneous transluminal angioplasty, and implantation of stents were used.

RESULTS AND CONCLUSIONS

Predictors of unfavorable outcome were diabetes mellitus (p<0.001) and symptomatic hemorrhages (p<0.001). The latter occurred in 5% of our population. Preliminary results of new techniques including sonothrombolysis, angiojet aspiration, and laser recanalization of thromboembolic occlusions are discussed.

The Basilar Artery International Cooperation Study (BASICS): study protocol for a randomised controlled trial

Background

Despite recent advances in acute stroke treatment, basilar artery occlusion (BAO) is associated with a death or disability rate of close to 70%. Randomised trials have shown the safety and efficacy of intravenous thrombolysis (IVT) given within 4.5 h and have shown promising results of intra-arterial thrombolysis given within 6 h of symptom onset of acute ischaemic stroke, but these results do not directly apply to patients with an acute BAO because only few, if any, of these patients were included in randomised acute stroke trials.

Recently the results of the Basilar Artery International Cooperation Study (BASICS), a prospective registry of patients with acute symptomatic BAO challenged the often-held assumption that intra-arterial treatment (IAT) is superior to IVT. Our observations in the BASICS registry underscore that we continue to lack a proven treatment modality for patients with an acute BAO and that current clinical practice varies widely.

Design

BASICS is a randomised controlled, multicentre, open label, phase III intervention trial with blinded outcome assessment, investigating the efficacy and safety of additional IAT after IVT in patients with BAO. The trial targets to include 750 patients, aged 18 to 85 years, with CT angiography or MR angiography confirmed BAO treated with IVT. Patients will be randomised between additional IAT followed by optimal medical care versus optimal medical care alone. IVT has to be initiated within 4.5 h from estimated time of BAO and IAT within 6 h. The primary outcome parameter will be favourable outcome at day 90 defined as a modified Rankin Scale score of 0–3.

Discussion

The BASICS registry was observational and has all the limitations of a non-randomised study. As the IAT approach becomes increasingly available and frequently utilised an adequately powered randomised controlled phase III trial investigating the added value of this therapy in patients with an acute symptomatic BAO is needed (clinicaltrials.gov: NCT01717755).

Mechanical thrombectomy with the Solitaire device in acute basilar artery occlusion

AIMS

To evaluate the efficacy and safety of mechanical thrombectomy with the Solitaire FR device in revascularization of patients with acute basilar artery occlusion (ABAO) and to identify the predictive factors for clinical outcome.

METHODS

This prospective single-center study included 31 patients with acute ischemic stroke attributable to ABAO treated within the first 24 h after onset of symptoms with the Solitaire device. Nineteen patients simultaneously received intravenous thrombolysis. Recanalization rates after stent retrieval were determined and the clinical outcome and mortality rate were assessed 180 days after treatment.

RESULTS

The mean ±SD age of the patients was 61±17 years, the median prethrombectomy NIH Stroke Scale score was 38 (IQR 9-38) and the median Glasgow Coma Scale (GCS) score was 7 (IQR 4-14). Successful recanalization (TICI 3 or 2b) was achieved in 23 patients (74%). Five symptomatic intracranial hemorrhages were related to the procedure. Ten symptomatic distal migrations of thrombotic material occurred. A favorable outcome, defined as a modified Rankin Score (mRS) of 0-2, was observed in 35% of patients (11/31). Overall mortality rate was 32% (10/31). In the univariate analysis, elevated baseline glucose (p=0.008) was significantly associated with a poor outcome (mRS >2), whereas a tendency towards significance was observed with age (p=0.06), GCS on admission (p=0.07) and symptom-related lesions on T2 sequences (p=0.10). Patients with successful recanalization tended to have a better outcome (p=0.20).

CONCLUSION

Mechanical thrombectomy with the Solitaire FR device can rapidly and effectively contribute to a high rate of recanalization and improve functional outcome in patients with ABAO and has an acceptable complication rate.

Basilar artery strokes in children: good outcomes with conservative medical treatment

AIM

To describe outcomes and outcome predictors in childhood basilar artery stroke (BAS).

METHOD

We prospectively enrolled children with BAS with or without basilar artery occlusion (BAO) in the Toronto Children's Stroke Registry from 1992 to 2009. We assessed presenting features and outcomes including Pediatric Stroke Outcome Measure scores.

RESULTS

Among 578 children with acute arterial ischemic stroke, 27 had BAS (4.6% including neonates, 6% excluding neonates). Twenty-four (14 males, 10 females) children met study criteria (mean age at stroke was 8 y 10 mo; range 0-17 y). Eleven children had BAO. Aspirin or anticoagulation was given to 15 children. None received tissue plasminogen activator or endovascular treatments. At mean follow-up (3 y 2 mo, range 1 mo-11 y 8 mo), 12 had a 'good outcome' (seven normal, five insignificant deficit) and 12 had 'poor outcome' (10 moderate or severe deficit, two acute deaths). Larger infarct size (≥50% of axial brainstem diameter) independently predicted poor outcome (p=0.02; odds ratio 21.2, 95% confidence interval 1.6-274.9) but not BAO, altered level of consciousness, or age.

INTERPRETATION

Compared with adults, in childhood BAS death is rare and survivors frequently have good outcomes. Aggressive endovascular interventions may not be justifiable in this population.

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

METHODS

Members of the writing committee were appointed by the American Stroke Association Stroke Council's Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council's Level of Evidence grading algorithm.

RESULTS

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

CONCLUSIONS

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.