Brain Circulation最新文献

Patients with neurofibromatosis undergo multiple surgeries during their lifetime, presenting as challenging scenarios to the perioperative team. We present the case report of a young male patient with type 1 neurofibromatosis scheduled for endovascular embolization of thoracic spinal arteriovenous malformation under general anesthesia. Associated vasculopathy included stented descending thoracic aortic coarctation, an unrepaired saccular aortic aneurysm (AA) distal to the stent suggestive of a type 1 endoleak, bilateral segmental pulmonary arterial thrombosis, bilateral subclavian artery stenosis, and a retroperitoneal neurofibroma compressing the coeliac artery. Our primary concerns were a possible periprocedural AA rupture becoming a surgical emergency, difficult vascular access, and perioperative thromboembolism. Periprocedural hemodynamic surges were avoided using continuous hemodynamic monitoring, adequate anesthetic depth, and analgesia. After an uneventful procedure, the patient was extubated with a smooth postoperative course. An in-depth knowledge about underlying pathophysiology, anticipation and preparedness for potential complications, and interdisciplinary coordinated teamwork serve to preserve patient outcomes.

Reperfusion therapy, which substantially promotes the vessel recanalization rate and improves clinical outcomes, remains the most effective treatment of acute ischemic stroke (AIS). However, a substantial number of patients are either unsuitable for recanalization therapy or experience limited recovery postreperfusion. There is growing recognition that adjunctive neuroprotective therapies may further improve the outcomes in AIS patients by protecting brain tissue during ischemia. Recent advancements in neuroprotective approaches, including pharmacologic agents such as nerinetide edaravone, and uric acid, as well as nonpharmacological interventions, such as remote ischemic conditioning and normobaric hyperoxia, offer promising potentials in stroke care. This review provides an overview of the current neuroprotective therapies, examines recent clinical evidence, and discusses the strengths and weaknesses of certain clinical trials aimed at cerebral protection.

Introduction: Mechanical thrombectomy (MT) is the standard of care for acute ischemic stroke for select patients with large vessel occlusion (LVO). Although racial disparities in the utilization of thrombectomy have been previously identified, disparities in the utilization of thrombectomy in a single center with a standardized patient selection protocol have not been described in the literature.

Methods: Using the American Heart Association Quality Improvement Programs Registry, we retrospectively reviewed the records of 1,143 patients with LVO between December 1, 2014, and May 31, 2021. Patient records were assessed for demographic data, stroke risk factors, process metrics, and success of thrombectomy. A Pearson's Chi-Squared and an independent two-sample t-test were used to determine the significance. Following this, a multivariate logistic regression was run to determine predictably of thrombectomy outcomes.

Results: Of the 1,143 LVO patients, 567 were male (49.6%), 576 were female, (50.4%), 963 were white (84.3%), and 180 were nonwhite (15.7%). Based on our Pearson's Chi-squared analysis, female patients were more like to undergo thrombectomy compared to male patients (62.4% vs. 48.9%; P < 0.001). White patients were also more likely to undergo thrombectomy compared to nonwhite patients (58.7% vs. 39.7%; P < 0.001). After the multivariate logistic regression analysis and after controlling for comorbidities, insurance status, age, time to presentation (last known well to arrival), transfer from outside hospital, and zip codes, white patients were 2.29 times more likely to receive a thrombectomy compared to nonwhite patients (odds ratio [OR], 2.29, 95% confidence interval [CI], 1.33, 3.944). Patients with Medicare insurance were 33.57 times more likely to receive a thrombectomy compared to those without medicare (OR, 33.57, 95% CI, 20.37, 55.327). In the regression model, sex did not contribute significantly to the likelihood of receiving a thrombectomy.

Conclusions: White patients were more likely to undergo MT. Female patients tended to have higher rates of MT, accounting for the fact that other variables could have influenced this. These disparities may result from a multitude of other factors such as eligibility for MT, delayed presentation, and adequate diagnosis of LVO in the emergency department. This study highlights the importance of and potential causes of these disparities. Further investigation with data from multiple centers is necessary to validate these findings and identify strategies for improving utilization of thrombectomy.

Background: The role of arterial collateral and venous outflow status on the response to intravenous tissue plasminogen activator (IV-tPA) has not been sufficiently clarified in acute major cerebral occlusions.

Patients and methods: A total of 130 patients (mean age: 71 years; 73 females) with acute middle cerebral artery M1/M2 segment or terminal internal carotid artery occlusion treated solely with IV-tPA were analyzed. Regional leptomeningeal score (rLMC) was used for cerebral arterial collateral scoring, and the cortical vein opacification score (COVES) and modified Prognostic Evaluation based on Cortical vein score difference In Stroke (PRECISE) superficial and deep scores were used for venous outflow profile. Exploratory logistic models for response to IV-tPA [positive response: National Institutes of Health Stroke Scale (NIHSS) decrease 4 (or decrease to 0) at 24 h; dramatic response: NIHSS decrease ≥8 (or decrease to 0 or 1)], functional outcome (modified Rankin's score 0-1 as "excellent" and 0-2 "good") and tPA-associated hemorrhagic transformation were constructed.

Results: IV-tPA efficacy was positive in 47% and dramatic in 32%. Dramatic response was linked to better arterial collateral status (exp[B] =1.115 [95% confidence interval (CI), 1.016-1.223]). Excellent outcome was noted in 26% and good in 45%. One-point increase in rLMC score independently increased good prognosis (exp[B] =1.209 [1.034-1.412]). Patients with good prognosis had higher (by 0.5 points) modified PRECISE deep score (P = 0.047) and less frequent nonsufficient modified PRECISE deep score (0-2) (P = 0.017) in univariate analyses. However, these associations failed to survive in multiple regression. Any type tPA-associated cerebral hemorrhagic transformation was observed in 23% and parenchymal hemorrhage type 2 in 5.4%. While rLMC score showed a borderline strength correlation to hemorrhage (exp[B] =0.899 [95% CI, 0.808-1.001]), outflow scores not.

Conclusion: While arterial collateral status modifies the effect of tPA in acute anterior circulation major artery occlusions, venous outflow capacity is not so critical.

Moyamoya disease (MMD) is a cerebrovascular disorder characterized by progressive occlusion of intracranial arteries, often leading to stroke and intracerebral hemorrhage. While MMD classically affects the intracranial vasculature, we present an unusual case of bilateral vertebral steno-occlusion, resulting in vertebrobasilar insufficiency in a 37-year-old man with MMD and treated with angioplasty and stenting of the dominant vertebral artery. Review of the literature demonstrates proximal vertebral artery involvement to be a rare manifestation of moyamoya disease. This report contributes to the understanding of the clinical spectrum of MMD and emphasizes the need for vigilance and awareness of the possibility of extracranial vascular complications in affected individuals.

Stroke remains a significant contributor to global morbidity and mortality, with acute ischemic stroke comprising the majority of cases. Secondary stroke, the recurrent stroke, is often more severe and linked to worse functional outcomes and increased mortality. The secondary prevention of ischemic stroke is crucial for reducing the risk of recurrent events. Significant advancements have been made in secondary prevention strategies in recent years. These include the refinement of antithrombotic regimens, the use of direct oral anticoagulants in managing atrial fibrillation, and the implementation of more aggressive targets for blood pressure, lipid management, and glucose management. Furthermore, emerging therapeutic approaches, such as remote ischemic conditioning and anti-inflammatory agents such as colchicine, have shown promise in reducing stroke recurrence through nontraditional mechanisms. This review summarizes the latest advancements in the secondary prevention of ischemic stroke over the past 5 years, highlighting the key clinical trials and novel interventions. The optimization of traditional risk factor management and the emergence of novel therapeutic methods have provided more options for clinical practice. Future research should focus on identifying the optimal treatment strategies for specific patient subgroups and the clinical translation and application of new therapeutic methods.

Background: In acute ischemic stroke (AIS), cerebral autoregulation becomes dysfunctional, impacting the brain's ability to maintain cerebral blood flow (CBF) at adequate levels. Reperfusion of affected and nearby brain tissue in AIS is currently the aim of treatment in AIS, but the effectiveness of fluid resuscitation on increasing the CBF is debated.

Objective: We investigated the hypothesis that early fluid resuscitation with normal saline bolus would improve CBF velocity in the initial resuscitation of patients with AIS.

Methods: We conducted a prospective, quasi-experimental study on 30 patients in the early stages of AIS management. Patients had a National Institutes of Health Stroke Scale (NIHSS) score of 3 or higher. Patients met inclusion criteria if they were 18-90 years old and had time of stroke onset within 12 h. Patients with a severe underlying disability, hemorrhagic stroke, advanced directives for comfort care/hospice, as well as pregnant patients were excluded. Noninvasive hemodynamic monitoring was performed. We performed transcranial Doppler (TCD) insonation of the middle cerebral arteries (MCAs) to measure CBF velocity. Each patient received a 500-ml normal saline crystalloid bolus as a standardized intervention, then had hemodynamic and TCD measurements repeated. Analysis was limited to patients with stroke confirmed with neuroimaging. Mean flow velocity (MFV) was compared before and postreceiving the bolus in the MCA ipsilateral to the ischemic location.

Results: Thirty patients were analyzed who had confirmed AIS. The mean age was 53 ± 13 years, 50% were female, and the median NIHSS was 6 (interquartile range: 4-7). Outcomes measured included various cerebrovascular and cardiovascular parameters. Infusion of 500-mL normal saline bolus produced increases in systolic blood pressure (+7 mmHg, 95% confidence interval [CI] 0.6-13 mmHg) and stroke volume (SV) index (+2.2 ml/m², 95% CI 0.3-4.1 ml/m²). The mean change in MFV was not statistically significant (+0.3 cm/s, 95% CI-3.7-4.3 cm/s). An adjusted model showed higher age and lower baseline SV index were not associated with improved MFV following administration of the fluid bolus.

Conclusion: Our prospective study of AIS patients revealed that a fluid bolus improves hemodynamic parameters, but did not significantly increase CBF velocity.

Trial registration: clinicaltrials.gov (identifier: NCT02056821).

Background: When a seizure occurs, the distribution of purine receptors in different cell types at various time points remains poorly understood. Our literature review revealed that P2X7, P2Y6, and P2Y12 are expressed in different cells during epilepsy pathogenesis. Therefore, we studied the protein expression patterns of the purinergic receptors P2X7, P2Y6, and P2Y12 in the normal mice hippocampus, as well as during or after pilocarpine-induced status epilepticus (DPISE or APISE).

Materials and methods: Immunohistochemical staining and double-labeling immunofluorescence staining were used to study the cellular distribution of various purinergic receptors across several groups: control, 2-hour DPISE, 1-day APISE, 2-day APISE, 3-day APISE, and 1-week APISE.

Results: In the normal mouse brain, P2X7, P2Y6, and P2Y12 were predominantly expressed in the neurons. Microglia and astrocytes were found to express these receptors at the onset of seizures. Immunofluorescence analysis showed that P2X7 and P2Y12 are expressed in microglia, whereas P2Y6 is mainly expressed in astrocytes.

Conclusion: Different purinergic receptors are expressed in neurons, microglia, and astrocytes, mediate their interactions, and are involved in epileptogenesis.

Background: Insulin resistance is more prevalent in the overweight population, which can affect their glucose metabolism. This study explores whether weight status influences the relationship between admission hyperglycemia and outcomes after thrombectomy.

Methods: Four hundred and fifty-two patients with acute anterior circulation ischemic stroke undergoing thrombectomy were retrospectively analyzed. Hyperglycemia at admission was described as venous blood glucose ≥7.8 mmol/L and overweight as body mass index ≥24 kg/m². The outcomes included the rates of functional independence (90-day modified Rankin Scale 0-2), symptomatic intracranial hemorrhage within 24 h after thrombectomy, and mortality at 90 days.

Results: Overall, hyperglycemia at admission decreased the likelihood of functional independence (adjusted odds ratio [OR] 0.50, 95% confidence interval [CI] 0.30-0.83, P = 0.008). Weight status modified the efficacy of admission hyperglycemia on functional independence (P = 0.022 for interaction). Hyperglycemia at admission was negatively associated with functional independence among overweight patients (adjusted OR 0.30, 95% CI 0.15-0.60, P = 0.001) but not among normal-weight patients (adjusted OR 1.13, 95% CI 0.48-2.70, P = 0.776). Weight status did not influence the efficacy of hyperglycemia at admission on mortality (P = 0.201 for interaction) or symptomatic intracerebral hemorrhage (P = 0.105 for interaction).

Conclusions: Weight status influenced the effect of hyperglycemia at admission on functional independence after thrombectomy. Hyperglycemia at admission was related to functional independence among overweight patients but not among normal-weight patients. Our findings suggest tight control of glucose may be needed for overweight patients in the thrombectomy setting.

Background: The optimal method for addressing cerebral ischemic stroke involves promptly restoring blood supply. However, cerebral ischemia-reperfusion injury (CIRI) is an unavoidable consequence of this event. Neuroinflammation is deemed the primary mechanism of CIRI, with various activation phenotypes of microglia playing a pivotal role. Research has demonstrated that long-lasting agonists of the glucagon-like peptide-1 receptor can suppress neuroinflammation and microglial activation.

Methods: A transient middle cerebral artery occlusion (tMCAO) rat model was established to investigate the effects of semaglutide. Neurological impairments were evaluated utilizing modified neurological severity score on days 1, 3, and 7 postinterventions. Brains were stained with 2,3,5-Triphenyltetrazolium Chloride to determine infarct volume. To assess the expression of various microglia activation phenotypes and neuroinflammatory biomarkers, we utilized immunohistochemistry and immunoblotting.

Results: The study demonstrated that semaglutide in the tMCAO model could decrease neurological deficit scores and reduce the size of cerebral infarcts. In addition, we observed low levels of cluster of differentiation 68 (CD68, an indicator of M1 microglial activation) and tumor necrosis factor alpha (a pro-inflammatory mediator). Moreover, the results indicated a rise in the levels of CD206 (an indicator of M2 activation) and transforming growth factor beta (an anti-inflammatory mediator), while simultaneously reducing P65 levels in the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling cascade.

Conclusion: In the CIRI model, semaglutide exhibits notable neuroprotective effects on rats, reducing neuroinflammation through the regulation of microglia phenotype transformation and inhibition of NF-κB activation.