Thrombectomy versus Medical Management for Isolated Anterior Cerebral Artery Stroke: An International Multicenter Registry Study.

Background Evidence supporting a potential benefit of thrombectomy for distal medium vessel occlusions (DMVOs) of the anterior cerebral artery (ACA) is, to the knowledge of the authors, unknown. Purpose To compare the clinical and safety outcomes between mechanical thrombectomy (MT) and best medical treatment (BMT) with or without intravenous thrombolysis for primary isolated ACA DMVOs. Materials and Methods Treatment for Primary Medium Vessel Occlusion Stroke, or TOPMOST, is an international, retrospective, multicenter, observational registry of patients treated for DMVO in daily practice. Patients treated with thrombectomy or BMT alone for primary ACA DMVO distal to the A1 segment between January 2013 and October 2021 were analyzed and compared by one-to-one propensity score matching (PSM). Early outcome was measured by the median improvement of National Institutes of Health Stroke Scale (NIHSS) scores at 24 hours. Favorable functional outcome was defined as modified Rankin scale scores of 0-2 at 90 days. Safety was assessed by the occurrence of symptomatic intracerebral hemorrhage and mortality. Results Of 154 patients (median age, 77 years; quartile 1 [Q1] to quartile 3 [Q3], 66-84 years; 80 men; 94 patients with MT; 60 patients with BMT) who met the inclusion criteria, 110 patients (median age, 76 years; Q1-Q3, 67-83 years; 50 men; 55 patients with MT; 55 patients with BMT) were matched. DMVOs were in A2 (82 patients; 53%), A3 (69 patients; 45%), and A3 (three patients; 2%). After PSM, the median 24-hour NIHSS point decrease was -2 (Q1-Q3, -4 to 0) in the thrombectomy and -1 (Q1-Q3, -4 to 1.25) in the BMT cohort (P = .52). Favorable functional outcome (MT vs BMT, 18 of 37 [49%] vs 19 of 39 [49%], respectively; P = .99) and mortality (MT vs BMT, eight of 37 [22%] vs 12 of 39 [31%], respectively; P = .36) were similar in both groups. Symptomatic intracranial hemorrhage occurred in three (2%) of 154 patients. Conclusion Thrombectomy appears to be a safe and technically feasible treatment option for primary isolated anterior cerebral artery occlusions in the A2 and A3 segment with clinical outcomes similar to best medical treatment with and without intravenous thrombolysis. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Zhu and Wang in this issue.

A clinical study of 288 patients with anterior cerebral artery infarction.

OBJECTIVE: Acute ischemic stroke in the territory of anterior cerebral artery (ACA) is uncommon. Therefore, large population studies evaluating ACA infarction are scarce. We sought to evaluate epidemiological and etiological characteristics of ACA infarction compared to other territorial infarctions. METHODS: We analyzed a prospectively collected stroke registry of all acute ischemic stroke patients for 19 years at two tertiary hospitals. We included patients with acute ischemic stroke caused by large vessel stenosis or occlusion including ACA, middle cerebral artery (MCA), posterior cerebral artery (PCA), and vertebrobasilar artery (VBA). RESULTS: A total of 4171 patients were enrolled. Patients with ACA infarction (N = 288) were significantly older with more females than those with MCA, PCA, or VBA infarction. There were more patients with history of prior ischemic stroke in the ACA infarction group than in other groups. The etiology of the ACA infarction was similar to those of the MCA, PCA and also the total population (66.7-71.8% of LAA and 17.9-20.9% of CE). When patients had prior ischemic stroke history, ACA infarction was more likely to be caused by LAA than MCA or PCA infarction (OR = 6.2, 95% CI 2.0-19.2, p = 0.002 and OR = 4.0, 95% CI 1.1-14.6, p = 0.038, respectively). CONCLUSIONS: Patients with ACA infarction had significantly more prior ischemic stroke than those with MCA, PCA, or VBA infarction. The etiology of ACA infarction in patients with prior ischemic stroke showed significantly more LAA than that of MCA or PCA infarction.

Topographic Evolution of Anterior Cerebral Artery Infarction and Its Impact on Motor Impairment.

INTRODUCTION: Motor deficit is common following anterior cerebral artery (ACA) stroke. This study aimed to determine the impact on the motor outcome, given the location of descending corticofugal fiber tracts (from the primary motor cortex [M1], dorsal and ventral premotor area [PMdv], and supplementary motor area [SMA]) and the regional variations in collateral support of the ACA territory. METHODS: Patients with ACA vessel occlusion were included. Disruption to corticofugal fibers was inferred by overlap of tracts with a lesion on computed tomography perfusion at the onset and on magnetic resonance imaging (MRI) poststroke. The motor outcome was defined by dichotomized and combined National Institute of Health Stroke Scale (NIHSS) sub-scores for the arm and leg. Multivariate hierarchical partitioning was used to analyze the proportional contribution of the corticofugal fibers to the motor outcome. RESULTS: Forty-seven patients with a median age of 77.5 (interquartile range 68.0-84.5) years were studied. At the stroke onset, 96% of patients showed evidence of motor deficit on the NIHSS, and the proportional contribution of the corticofugal fibers to motor deficit was M1-33%, SMA-33%, and PMdv-33%. By day 7, motor deficit was present in <50% of patients and contribution of M1 fiber tracts to the motor deficit was reduced (M1-10.2%, SMA-61.0%, PMdv-28.8%). We confirmed our findings using publicly available high-resolution templates created from Human Connectome Project data. This also showed a reduction in involvement of M1 fiber tracts on initial perfusion imaging (33%) compared to MRI at a median time of 7 days poststroke (11%). CONCLUSION: Improvements in the motor outcome seen in ACA stroke may be due to the relative sparing of M1 fiber tracts from infarction. This may occur as a consequence of the posterior location of M1 fiber tracts and the evolving topography of ACA stroke due to the compensatory capacity of leptomeningeal anastomoses.

Expedient assessment of post-infarct remodeling by native cardiac magnetic resonance imaging in mice.

Novel therapeutic strategies aiming at improving the healing process after an acute myocardial infarction are currently under intense investigation. The mouse model plays a central role for deciphering the underlying mechanisms on a molecular and cellular level. Therefore, we intended to assess in-vivo post-infarct remodeling as comprehensively as possible using an expedient native magnetic resonance imaging (MRI) in the two most prominent infarct models, permanent ligation (PL) of the left anterior descending artery (LAD) versus ischemia reperfusion (I/R). Mice were subjected to either permanent or transient (45 min) occlusion of the LAD. After 3 weeks, examinations were performed with a 7-Tesla small animal MRI system. Data analysis was performed with the freely available software Segment. PL resulted in a massive dilation of the left ventricle, accompanied by hypertrophy of the non-infarcted myocardium and a decline of contractile function. These effects were less pronounced following I/R compared to healthy animals. Single plane assessments were not sufficient to capture the specific differences of left ventricular (LV) properties between the two infarct models. Bulls-eye plots were found to be an ideal tool for qualitative LV wall assessment, whereas a multi-slice sector-based analysis of wall regions is ideal to determine differences in hypertrophy, lateral wall thinning and wall thickening on a quantitative level. We combine the use of polar map-based analysis of LV wall properties with volumetric measurements using simple CINE CMR imaging. Our strategy represents a versatile and easily available tool for serial assessment of the LV during the remodeling process. Our study contributes to a better understanding of the effects of novel therapies targeting the healing of damaged myocardium.

Bilateral asterixis in a patient with bilateral anterior cerebral artery infarction.

A 83-year-old woman complained of muscular weakness in the left leg and trembling in all extremities. She was apathetic and had left leg paresis and asterixis in all extremities. Magnetic resonance imaging revealed acute cerebral infarctions in the bilateral frontal lobes perfused by the anterior cerebral artery (ACA). Anticoagulant treatments improved ischemia-induced damage of the frontal lobes, and then her neurological symptoms including asterixis gradually disappeared. A unique point of this case is that acute stroke in the bilateral ACA territory induced bilateral asterixis resembling metabolic encephalopathy. Occurrence of the bilateral ACA territory infarction is extremely rare, but it should be considered in patients presenting with bilateral asterixis.

Anterior Cerebral Artery Stroke: Role of Collateral Systems on Infarct Topography.

Background and Purpose: The circle of Willis (CoW) and leptomeningeal anastomoses play an important role in transforming infarct topography following middle cerebral artery occlusion. Their role in infarct topography following anterior cerebral artery occlusion is not well understood. The aim of this study was to evaluate the role of the CoW and leptomeningeal anastomoses in modifying regional variation in infarct topography following occlusion of the anterior cerebral artery and its branches. Methods: Perfusion and magnetic resonance imaging of patients with anterior cerebral artery stroke and evidence of vessel occlusion were segmented and manually registered to standard brain template for voxel-wise comparison. Next, a computer model of the cerebral arteries was formulated as network of nodes connected by cylindrical pipes. The experiments included occlusion of successive branches of the anterior cerebral artery while the configurations of the CoW were varied. Results: Forty-seven patients with a median age of 77.5 years (interquartile range, 68.0­84.5 years) were studied. The regions with the highest probabilities of infarction were the superior frontal gyrus (probability =0.26) and anterior cingulate gyrus (probability =0.24). The regions around the posterior cingulate gyrus (probability =0.08), paracentral lobule (probability =0.05), precuneus and superior parietal lobule (probability =0.03) had a low probability of infarction. Following occlusions distal to the anterior communicating artery, the computer model demonstrated an increase in flow (>30%) in neighboring cortical arteries with leptomeningeal anastomoses. Conclusions: Traditionally the CoW has been regarded as the primary collateral system. However, our computer model shows that the CoW is only helpful in redirecting flow following proximal vessel occlusions (pre-anterior communicating artery). More important are leptomeningeal anastomoses, which play an essential role in distal vessel occlusions, influencing motor outcome by modifying the posterolateral extent of infarct topography.

Clinical prognosis of isolated anterior cerebral artery territory infarction: a retrospective study.

BACKGROUND: Isolated anterior cerebral artery territory (ACA) infarction is a rare phenomenon, and is known to have distinctive clinical features. Little is known regarding the clinical prognosis of isolated ACA territory infarction with associated factors, and its impact on dwelling and job status. We investigated the short- and long-term outcomes of anterior cerebral artery (ACA) territory infarction, and the associated factors involved in the development of the distinctive symptoms. METHODS: This retrospective study in a prospective cohort of acute ischaemic stroke patients included consecutively enrolled patients with isolated ACA territory infarction. We investigated the functional status using the modified Rankin scale (mRS) score at discharge, three months' post-discharge, and one-year post-discharge. We also investigated the occlusion site of the ACA (proximal vs. distal); presence of distinctive symptoms of ACA territory infarction including behaviour changes, indifference, aphasia, and urinary incontinence; and the effect of these symptoms on dwelling and job status one year after discharge. RESULTS: Between April 2014 and March 2019, 47 patients with isolated ACA territory infarction were included. Twenty-nine patients (61.7 %) had good outcomes (mRS ≤ 2) at discharge; however, the mRS score increased at three months (40; 85.1 %, p < 0.001) and one year (41; 87.2 %) post-discharge. Occlusion of the ACA proximal segment was independently associated with the development of distinctive symptoms (adjusted odds ratio, 17.68; 95 % confidence interval: 2.55-122.56, p < 0.05). Twenty-one (48.8 %) patients with good outcomes at one year experienced a change in dwelling status and job loss; 20 (95.2 %) of them had distinctive ACA territory symptoms with proximal ACA occlusion. CONCLUSIONS: Short- and long-term outcomes of isolated ACA territory infarction were favourable. However, proximal segment occlusion was associated with the development of distinctive symptoms, possibly related to future dwelling and job status.

Mechanical Thrombectomy in Medium Vessel Occlusions: Blind Exchange With Mini-Pinning Technique Versus Mini Stent Retriever Alone.

BACKGROUND AND PURPOSE: Mechanical thrombectomy techniques for intracranial medium vessel occlusions (MeVOs) have evolved in recent years, although the optimal approach is still unclear. The aim of this study was to investigate the effectiveness and safety of mechanical thrombectomy in MeVOs using mini (0.017 inches microcatheter compatible) stent retrievers combined with low-profile (0.035 inches distal inner diameter) distal aspiration catheters through the blind exchange/mini-pinning (BEMP) technique compared with mini stent retrievers alone. METHODS: Retrospective review of a prospectively maintained database of patients treated with the BEMP technique or mini stent retriever alone for intracranial MeVOs from 2017 to 2020 in a comprehensive stroke center. Both groups were compared about baseline characteristics, occlusion site, clinical presentation, clot cause, procedural outcomes (MeVO first-pass and final expanded Thrombolysis in Cerebral Ischemia score, the mini stent retriever used, number of passes with the front-line approach, and need of rescue therapy), safety outcomes (emboli to unwanted territories and hemorrhagic complications), and clinical outcomes at 90 days. Multivariable logistic regression analysis was performed with potential predictors of vessel recanalization to find independent variables associated with MeVO first-pass expanded Thrombolysis in Cerebral Ischemia 2c/3 recanalization. RESULTS: We reviewed 102 patients/106 MeVOs treated with the BEMP technique (n=56) or mini stent retriever (n=50). There was a higher rate of MeVO first-pass expanded Thrombolysis in Cerebral Ischemia 2c/3 recanalization (57% versus 34%, P=0.017), lower need of rescue therapy (7.1% versus 22%, P=0.028), and lower rate of emboli to new territory (1.8% versus 12%, P=0.035) and symptomatic intracranial hemorrhage (1.9% versus 12.8%, P=0.038) with the BEMP technique. After multivariable analysis, the sole independent factor associated to MeVO first-pass expanded Thrombolysis in Cerebral Ischemia 2c/3 recanalization was the BEMP technique (odds ratio, 2.72 [95% CI, 1.19-6.22]; P=0.018). CONCLUSIONS: In the setting of MeVOs, the BEMP technique may lead to higher rates of the first-pass recanalization and a lower incidence of symptomatic intracranial hemorrhage than mini stent retrievers alone.

Clinical Course of Acute Ischemic Stroke Due to Medium Vessel Occlusion With and Without Intravenous Alteplase Treatment.

BACKGROUND AND PURPOSE: Available data on the clinical course of patients with acute ischemic stroke due to medium vessel occlusion (MeVO) are mostly limited to those with M2 segment occlusions. Outcomes are generally better compared with more proximal occlusions, but many patients will still suffer from severe morbidity. We aimed to determine the clinical course of acute ischemic stroke due to MeVO with and without intravenous alteplase treatment. METHODS: Patients with MeVO (M2/M3/A2/A3/P2/P3 occlusion) from the INTERRSeCT (The Identifying New Approaches to Optimize Thrombus Characterization for Predicting Early Recanalization and Reperfusion With IV Alteplase and Other Treatments Using Serial CT Angiography) and PRoveIT (Precise and Rapid Assessment of Collaterals Using Multi-Phase CTA in the Triage of Patients With Acute Ischemic Stroke for IA Therapy) studies were included. Baseline characteristics and clinical outcomes were summarized using descriptive statistics. The primary outcome was a modified Rankin Scale score of 0 to 1 at 90 days, describing excellent functional outcome. Secondary outcomes were the common odds ratio for a 1-point shift across the modified Rankin Scale and functional independence, defined as modified Rankin Scale score of 0 to 2. We compared outcomes between patients with versus without intravenous alteplase treatment and between patients who did and did not show recanalization on follow-up computed tomography angiography. Logistic regression was used to provide adjusted effect-size estimates. RESULTS: Among 258 patients with MeVO, the median baseline National Institutes of Health Stroke Scale score was 7 (interquartile range: 5-12). A total of 72.1% (186/258) patients were treated with intravenous alteplase and in 41.8% (84/201), recanalization of the occlusion (revised arterial occlusive lesion score 2b/3) was seen on follow-up computed tomography angiography. Excellent functional outcome was achieved by 50.0% (129/258), and 67.4% (174/258) patients gained functional independence, while 8.9% (23/258) patients died within 90 days. Recanalization was observed in 21.4% (9/42) patients who were not treated with alteplase and 47.2% (75/159) patients treated with alteplase (P=0.003). Early recanalization (adjusted odds ratio, 2.29 [95% CI, 1.23-4.28]) was significantly associated with excellent functional outcome, while intravenous alteplase was not (adjusted odds ratio, 1.70 [95% CI, 0.88-3.25]). CONCLUSIONS: One of every 2 patients with MeVO did not achieve excellent clinical outcome at 90 days with best medical management. Early recanalization was strongly associated with excellent outcome but occurred in <50% of patients despite intravenous alteplase treatment.

Multimodal Predictive Modeling of Endovascular Treatment Outcome for Acute Ischemic Stroke Using Machine-Learning.

BACKGROUND AND PURPOSE: This study assessed the predictive performance and relative importance of clinical, multimodal imaging, and angiographic characteristics for predicting the clinical outcome of endovascular treatment for acute ischemic stroke. METHODS: A consecutive series of 246 patients with acute ischemic stroke and large vessel occlusion in the anterior circulation who underwent endovascular treatment between April 2014 and January 2018 was analyzed. Clinical, conventional imaging (electronic Alberta Stroke Program Early CT Score, acute ischemic volume, site of vessel occlusion, and collateral score), and advanced imaging characteristics (CT-perfusion with quantification of ischemic penumbra and infarct core volumes) before treatment as well as angiographic (interval groin puncture-recanalization, modified Thrombolysis in Cerebral Infarction score) and postinterventional clinical (National Institutes of Health Stroke Scale score after 24 hours) and imaging characteristics (electronic Alberta Stroke Program Early CT Score, final infarction volume after 18-36 hours) were assessed. The modified Rankin Scale (mRS) score at 90 days (mRS-90) was used to measure patient outcome (favorable outcome: mRS-90 ≤2 versus unfavorable outcome: mRS-90 >2). Machine-learning with gradient boosting classifiers was used to assess the performance and relative importance of the extracted characteristics for predicting mRS-90. RESULTS: Baseline clinical and conventional imaging characteristics predicted mRS-90 with an area under the receiver operating characteristics curve of 0.740 (95% CI, 0.733-0.747) and an accuracy of 0.711 (95% CI, 0.705-0.717). Advanced imaging with CT-perfusion did not improved the predictive performance (area under the receiver operating characteristics curve, 0.747 [95% CI, 0.740-0.755]; accuracy, 0.720 [95% CI, 0.714-0.727]; P=0.150). Further inclusion of angiographic and postinterventional characteristics significantly improved the predictive performance (area under the receiver operating characteristics curve, 0.856 [95% CI, 0.850-0.861]; accuracy, 0.804 [95% CI, 0.799-0.810]; P<0.001). The most important parameters for predicting mRS 90 were National Institutes of Health Stroke Scale score after 24 hours (importance =100%), premorbid mRS score (importance =44%) and final infarction volume on postinterventional CT after 18 to 36 hours (importance =32%). CONCLUSIONS: Integrative assessment of clinical, multimodal imaging, and angiographic characteristics with machine-learning allowed to accurately predict the clinical outcome following endovascular treatment for acute ischemic stroke. Thereby, premorbid mRS was the most important clinical predictor for mRS-90, and the final infarction volume was the most important imaging predictor, while the extent of hemodynamic impairment on CT-perfusion before treatment had limited importance.

Response to Speech and Language Therapy According to Artery Involvement and Lesion Location in Post-stroke Aphasia.

PURPOSE: Aphasia is one of the most common complications after stroke and occurs in 21-38% of the patients during acute period. The present study aimed to investigate the response to speech and language therapy according to artery involvement and lesion location in patients with post-stroke aphasia. METHOD: The medical records of 107 patients with post-stroke aphasia (mean age, 58.8 ± 14.8 years) who were admitted to a single rehabilitation center for usual care after stroke were reviewed. Location of the ischemic lesion and involved artery was determined assessing the brain MRI of the patients. All the patients received 24 sessions speech and language therapy (3 days a week) as a part of 8-week rehabilitation program. Evaluation of the aphasia was performed with Gülhane Aphasia Test-2 (GAT-2) at baseline and at the end of the rehabilitation program. RESULTS: Baseline GAT-2 scores was significantly worse in patients with middle cerebral artery (MCA) involvement compared to patients with other artery involvements (p = 0.007). While the GAT-2 scores of patients with MCA involvement were improved significantly after speech and language therapy (p < 0.001), the changes in those with anterior cerebral artery (ACA) and posterior cerebral artery (PCA) involvements were not significant (p > 0.05). CONCLUSIONS: The present findings suggested that speech functions might be more affected in ischemic lesion of MCA and response to SLT might be better in patients with MCA involvement.

Clinical course of a 66-year-old man with an acute ischaemic stroke in the setting of a COVID-19 infection.

A 66-year-old man was admitted to hospital with a right frontal cerebral infarct producing left-sided weakness and a deterioration in his speech pattern. The cerebral infarct was confirmed with CT imaging. The only evidence of respiratory symptoms on admission was a 2 L oxygen requirement, maintaining oxygen saturations between 88% and 92%. In a matter of hours this patient developed a greater oxygen requirement, alongside reduced levels of consciousness. A positive COVID-19 throat swab, in addition to bilateral pneumonia on chest X-ray and lymphopaenia in his blood tests, confirmed a diagnosis of COVID-19 pneumonia. A proactive decision was made involving the patients' family, ward and intensive care healthcare staff, to not escalate care above a ward-based ceiling of care. The patient died 5 days following admission under the palliative care provided by the medical team.

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

BACKGROUND AND PURPOSE: Reports are emerging regarding the association of acute ischemic strokes with large vessel occlusion and coronavirus disease 2019 (COVID-19). While a higher severity of these patients could be expected from the addition of both respiratory and neurological injury, COVID-19 patients with strokes can present with mild or none respiratory symptoms. We aimed to compare anterior circulation large vessel occlusion strokes severity between patients with and without COVID-19. METHODS: We performed a comparative cohort study between patients with COVID-19 who had anterior circulation large vessel occlusion and early brain imaging within 3 hours from onset, in our institution during the 6 first weeks of the COVID-19 outbreak and a control group admitted during the same calendar period in 2019. RESULTS: Twelve COVID-19 patients with anterior circulation large vessel occlusion and early brain imaging were included during the study period and compared with 34 control patients with anterior circulation large vessel occlusion and early brain imaging in 2019. Patients in the COVID-19 group were younger (P=0.032) and had a history of diabetes mellitus more frequently (P=0.039). Patients did not significantly differ on initial National Institutes of Health Stroke Scale nor time from onset to imaging (P=0.18 and P=0.6, respectively). Patients with COVID-19 had more severe strokes than patients without COVID-19, with a significantly lower clot burden score (median: 6.5 versus 8, P=0.016), higher rate of multivessel occlusion (50% versus 8.8%, P=0.005), lower DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Scores; median: 5 versus 8, P=0.006), and higher infarct core volume (median: 58 versus 6 mL, P=0.004). Successful recanalization rate was similar in both groups (P=0.767). In-hospital mortality was higher in the COVID-19 patients' group (41.7% versus 11.8%, P=0.025). CONCLUSIONS: Early brain imaging showed higher severity large vessel occlusion strokes in patients with COVID-19. Given the massive number of infected patients, concerns should be raised about the coming neurovascular impact of the pandemic worldwide.