Subarachnoid haemorrhage: what happens to the cerebral arteries?

Intimal Hemorrhage of Basilar Artery Induced by Severe Vasospasm Following Subarachnoid Hemorrhage: The Experimental Analysis

BACKGROUND

 Cerebral vasospasm, a serious complication of subarachnoid hemorrhage (SAH), has been extensively studied for its neurochemical and pathophysiologic mechanisms. However, the contribution of inner elastic membrane dissection and subintimal hemorrhage to basilar artery occlusion remains underexplored. This study investigates inner elastic membrane-related changes in the basilar artery after SAH.

METHODS

 Twenty-four hybrid rabbits were divided into control, sham, and SAH groups, with SAH induced by autologous blood injection. After 2 weeks, basilar artery changes, vasospasm indexes (VSIs), and dissections were evaluated.

RESULTS

 The SAH group showed significantly higher VSI, with vascular wall thickening, luminal narrowing, convoluted smooth muscle cells, intimal elastic membrane disruption, endothelial cell desquamation, and apoptosis. Some SAH animals exhibited subintimal hemorrhage, inner elastic membrane dissection, and ruptures. Basilar arteries with subintimal hemorrhage had notably higher VSI.

CONCLUSIONS

 These findings highlight the role of subintimal hemorrhage and inner elastic membrane dissection in basilar artery occlusion post-SAH, offering valuable insights into vasospasm pathophysiology.

Microsurgical clipping and endovascular intervention for middle cerebral artery aneurysm: A meta-analysis

BACKGROUND

The purpose of this study is to compare the prognosis and effective rate of interventional embolization and surgical clipping in the treatment of middle cerebral artery aneurysms, to provide evidence-based basis for the selection of clinical treatment.

METHODS

By searching PubMed, Cochrane library, Medline, Embase and other databases, we collected the related studies interventional embolization and surgical clipping in the treatment of middle cerebral artery aneurysms, whether it was a randomized controlled trial or not. According to the relevant inclusion and exclusion criteria, 2 researchers independently screened and extracted the relevant data. Quality of life, residual neck and recurrence rate, incidence of ischemic cerebral infarction, intracranial infection rate, incidence of vasospasm and rebleeding rate were measured. Revman5.4 software was used for Meta-analysis.

RESULTS

There were 3658 patients included in 30 literatures, including 1478 patients treated with interventional embolization and 2180 patients treated with surgical clipping. The rate of low quality of life (odds ratio [OR] = 1.68, 95% confidence interval [CI]: 1.36-2.07, P < .00001) and intracranial infection rate (OR = 8.79,95% CI: 4.47-17.27, P < .00001) in the interventional embolization group were lower than those in the surgical clipping group. The postoperative rebleeding rate (OR = 0.46, 95% CI: 0.29-0.73, P = .0009), residual neck and recurrence rate (OR = 0.32, 95% CI: 0.24-0.43, P < .00001) in the interventional embolization group were higher than those in the surgical clipping group. The heterogeneity of residual neck and recurrence rate were high, so subgroup analysis was performed. We divide them into short-term group (OR = 0.68, 95% CI: 0.40-1.13, P = .13) and long-term group (OR = 0.23, 95% CI: 0.16-0.33, P < .00001). The results showed that the residual neck and recurrence rate in the interventional embolization group were higher than those in the surgical clipping group. There was no significant difference in the incidence of cerebral vasospasm (OR = 1.09, 95% CI: 0.64-1.86, P = .74) and ischemic stroke (OR = 0.87, 95% CI: 0.63-1.19, P = .37) between the 2 treatments.

CONCLUSION

According to the current clinical research evidence, compared with interventional embolization in the treatment of middle cerebral artery aneurysms, the quality of life of patients after clipping is lower, the incidence of intracranial infection is higher, but the residual neck, and recurrence rate are reduced. The risk of rebleeding is also reduced. There was no significant difference in the incidence of vasospasm and ischemic stroke between the 2 groups.

Treatment of aneurysmal subarachnoid hemorrhage in subacute phase; retrospective comparison of treatment in sub- and hyper-acute phases

OBJECTIVE

As soon as possible treatment initiation for aneurysmal subarachnoid hemorrhage (aSAH) is recommended. However, some patients require treatment in "subacute" phase of aSAH, defined in this study as "more than one day after the onset". To establish an optimal treatment strategy for these patients, we retrospectively analyzed the clinical experience of treating ruptured aneurysm with either clipping or coiling in subacute phase.

METHODS

Patients treated for aSAH between 2015 and 2021were analyzed. Patients were divided into the hyperacute phase (within 24 h) and subacute phase (later than 24 h) groups. The subacute group was analyzed to determine whether the selected procedure and its timing affected postoperative course and clinical outcomes. In addition, we conducted a multivariate logistic regression analysis to determine the independent factors that affect clinical outcomes.

RESULTS

Of 215 patients, 31 were treated in the subacute phase. While cerebral vasospasm at initial imaging was more frequently observed in subacute group, there was no difference in incidence of postoperative vasospasms. Patients in subacute group seemed to have better clinical outcomes due to the milder severity at the time of treatment initiation. Risk of angiographic vasospasm seemed to be higher in patients treated with clipping than coiling, while no difference was seen in clinical outcomes. Multivariate logistic regression analysis showed that the timing and selected treatment did not significantly affect the clinical outcome or the occurrence of delayed vasospasm.

CONCLUSIONS

Treatment of aSAH in the subacute phase may also result in favorable clinical outcomes, similar to patients treated in the hyperacute phase with mild presentation. However, further investigations are required to establish the optimal treatment strategies for such patients.

Comprehensive Analysis of Endoplasmic Reticulum Stress in Intracranial Aneurysm

Background

Aberrant endoplasmic reticulum stress (ERS) plays an important role in multiple cardiovascular diseases. However, their implication in intracranial aneurysms (IAs) remains unclear. We designed this study to explore the general expression pattern and potential functions of ERS in IAs.

Methods

Five Gene Expression Omnibus (GEO) microarray datasets were used as the training cohorts, and 3 GEO RNA sequencing (RNA-seq) datasets were used as the validating cohorts. Differentially expressed genes (DEGs), functional enrichment, Lasso regression, logistic regression, ROC analysis, immune cell profiling, vascular smooth muscle cell (VSMC) phenotyping, weighted gene coexpression network analysis (WGCNA), and protein-protein interaction (PPI) analysis were applied to investigate the role of ERS in IA. Finally, we predicted the upstream transcription factor (TF)/miRNA and potential drugs targeting ERS.

Results

Significant DEGs were majorly associated with ERS, autophagy, and metabolism. Eight-gene ERS signature and IRE1 pathway were identified during the IA formation. WGCNA showed that ERS was highly associated with a VSMC synthesis phenotype. Next, ERS-VSMC-metabolism-autophagy PPI and ERS-TF-miRNA networks were constructed. Finally, we predicted 9 potential drugs targeting ERS in IAs.

Conclusion

ERS is involved in IA formation. Upstream and downstream regulatory networks for ERS were identified in IAs. Novel potential drugs targeting ERS were also proposed, which may delay IA formation and progress.

Methodological assessment of guidelines for the diagnosis and management of cerebral vasospasm using the AGREE-II tool

OBJECTIVE

Rupture of an intracranial aneurysm is the most common cause of spontaneous subarachnoid hemorrhage. Despite the recent advances in its early detection, diagnosis, and proper treatment, the outcome of patients experiencing aneurysmal subarachnoid hemorrhage (aSAH) remains poor. It is well known that cerebral vasospasm is the most troublesome complication of aSAH, while delayed cerebral ischemia related to cerebral vasospasm constitutes the major cause of unfavorable outcomes in patients with aSAH. The need for evidence-based guidelines is of great importance for the prevention, early detection, and efficient management of aSAH-induced vasospasm. Moreover, guidelines provide young physicians with a valuable tool for practicing defensible medicine. However, the methodology, clinical applicability, reporting clarity, and biases of guidelines must be periodically assessed. In this study, the authors sought to assess the reporting clarity and methodological quality of published guidelines and recommendations.

METHODS

A search was performed in the PubMed, Scopus, and Web of Science databases. The search terms used were "clinical practice guidelines," "recommendations," "stroke," "subarachnoid hemorrhage," and "vasospasm" in all possible combinations. The search period extended from 1964 to September 2021 and was limited to literature published in the English language. All published guidelines and recommendations reporting on the diagnosis and management of vasospasm were included. Studies other than those reporting guidelines and recommendations were excluded. The eligible studies were evaluated by three blinded raters, employing the Appraisal of Guidelines for Research & Evaluation II (AGREE-II) analysis tool.

RESULTS

A total of 10 sets of guidelines were evaluated in this study. The American Heart Association/American Stroke Association issued guidelines found to have the highest methodological quality and reporting clarity, followed by the European Stroke Organization guidelines and the English edition of the Japanese guidelines issued by the Japanese Society on Surgery for Cerebral Stroke. The interrater agreement was moderate in the current analysis.

CONCLUSIONS

These findings support the idea that improvement of currently existing guidelines is feasible in the following domains: the rigor of guidelines and recommendations development, clinical applicability, editorial independence, and stakeholder involvement. Furthermore, periodic updating of published guidelines requires improvement in the future.

Multiple lessons learned from a single case: Complications from pineal germinoma management

Background:

Pineal tumors are uncommon tumors that affect <1% of adults, with 50% of them being germinomas. A combination of endoscopic third ventriculostomy (ETV) and tumor biopsy is usually used. Cerebral vasospasm in association with aneurysmal subarachnoid hemorrhage (aSAH) has been extensively studied. However, at least according to the research, this is not the case in intraventricular hemorrhage (IVH) cases. We present a case with two distinct findings: (1) an unexpected large IVH following the removal of an external ventricular drain (EVD) in a patient who had undergone ETV and tumor biopsy, resulting in severe clinical vasospasm and (2) incidental pineal region germinoma regression on follow-up magnetic resonance imaging (MRI) without any prior adjuvant chemoradiation to explain such regression.

Case Description:

The authors describe an 18-year-old male patient who had a routine, uneventful combined ETV and tumor biopsy, as well as the placement of an EVD. Histopathological examination revealed germinoma. His postoperative course was complicated by IVH after EVD removal, which resulted in clinical vasospasm. Without any prior adjuvant chemoradiation, follow-up MRI of the b rain revealed a significant reduction in the size of the germinoma as well as reconstitution of the patency of the previously obstructed aqueduct of Sylvius.

Conclusion:

The take-home message from this case is that in the case of postoperative clinical deterioration in a patient with concurrent IVH and ETV, a high index of suspicion for vasospasm is required, as this may allow a significant amount of blood to pass down to the basal cisterns. Early detection and management of clinical vasospasm are critical for a better neurological outcome. Furthermore, unexpected tumor size changes can occur due to a variety of factors, so recent preoperative MRI of the brain should be obtained in the lead-up to surgery, and postoperative computed tomography should be used sparingly to avoid radiation-related tumor changes.

Regulation of cerebral blood flow in humans: physiology and clinical implications of autoregulation

Brain function critically depends on a close matching between metabolic demands, appropriate delivery of oxygen and nutrients, and removal of cellular waste. This matching requires continuous regulation of cerebral blood flow (CBF), which can be categorized into four broad topics: 1) autoregulation, which describes the response of the cerebrovasculature to changes in perfusion pressure; 2) vascular reactivity to vasoactive stimuli [including carbon dioxide (CO2)]; 3) neurovascular coupling (NVC), i.e., the CBF response to local changes in neural activity (often standardized cognitive stimuli in humans); and 4) endothelium-dependent responses. This review focuses primarily on autoregulation and its clinical implications. To place autoregulation in a more precise context, and to better understand integrated approaches in the cerebral circulation, we also briefly address reactivity to CO2 and NVC. In addition to our focus on effects of perfusion pressure (or blood pressure), we describe the impact of select stimuli on regulation of CBF (i.e., arterial blood gases, cerebral metabolism, neural mechanisms, and specific vascular cells), the interrelationships between these stimuli, and implications for regulation of CBF at the level of large arteries and the microcirculation. We review clinical implications of autoregulation in aging, hypertension, stroke, mild cognitive impairment, anesthesia, and dementias. Finally, we discuss autoregulation in the context of common daily physiological challenges, including changes in posture (e.g., orthostatic hypotension, syncope) and physical activity.

A Nomogram for Predicting the Need of Postoperative Tracheostomy in Patients With Aneurysmal Subarachnoid Hemorrhage

Objective: Early identification for the need of tracheostomy (TT) in aneurysmal subarachnoid hemorrhage (aSAH) patients remains one of the main challenges in clinical practice. Our study aimed to establish and validate a nomogram model for predicting postoperative TT in aSAH patients.

Methods: Patients with aSAH receiving active treatment (interventional embolization or clipping) in our institution between June 2012 and December 2018 were retrospectively included. The effects of patients' baseline information, aneurysm features, and surgical factors on the occurrence of postoperative TT were investigated for establishing a nomogram in the training cohort with 393 patients. External validation for the nomogram was performed in the validation cohort with 242 patients.

Results: After multivariate analysis, higher age, high neutrophil-to-lymphocyte ratio (NLR), high World Federation of Neurological Surgeons Scale (WFNS), and high Barrow Neurological Institute (BNI) grade were left in the final logistic regression model. The predictive power of the model was excellent in both training cohort and validation cohort [area under the curve (AUC): 0.924, 95% confidence interval [CI]: 0.893–0.948; AUC: 0.881, 95% CI: 0.833–0.919]. A nomogram consisting of these factors had a C-index of 0.924 (95% CI: 0.869–0.979) in the training cohort and was validated in the validation cohort (C-index: 0.881, 95% CI: 0.812–0.950). The calibration curves suggested good match between prediction and observation in both training and validation cohorts.

Conclusion: Our study established and validated a nomogram model for predicting postoperative TT in aSAH patients.

Transcranial Doppler ultrasonography (uses, limitations, and potentials): a review article

Background

The additional information that transcranial Doppler can provide as part of a multimodal imaging protocol in many clinical settings has not been evaluated.

Main body

Transcranial Doppler is a bedside procedure used to assess cerebral blood flow velocity via cerebral circulation and pulsatility index (PI). Many diseases can lead to cerebral vessels vasospasm as in subarachnoid hemorrhage and trauma. Cerebral vessels vasospasm represented by abnormal elevation of cerebral blood flow velocity. Intracranial pressure can be monitored by pulsatility index which reflects blood flow resistance in cerebral vessels. Transcranial Doppler ultrasonography is also the unique modality for detection of micro emboli in high-risk patients. Also, it can be used for evaluation of circulatory arrest with subsequent confirmation of brain death

Conclusion

Transcranial Doppler ultrasonography is the only diagnostic modality that provides a reliable assessment of cerebral blood flow patterns in real time. The physiological information obtained from TCD is complementary to the anatomical details obtained from other neuroimaging modalities. TCD is relatively cheap, can be performed bedside, and allows monitoring in acute emergency settings.

The Potential Role of hsa_circ_0005505 in the Rupture of Human Intracranial Aneurysm

Objective: Recently, abundant number of studies have revealed many functions of circular RNAs in multiple diseases, however, the role of circular RNA in the rupture of human intracranial aneurysm is still unknown. This study aims to explore the potential functions of circular RNA in the rupture of human intracranial aneurysms.

Methods: The differentially expressed circular RNAs between un-ruptured intracranial aneurysms (n = 5) and ruptured intracranial aneurysms (n = 5) were analyzed with the Arraystar human circRNAs microarray. Quantitative real-time PCR (qPCR) was used to verify the results of the circRNA microarray. The role of circular RNA in intracranial aneurysm rupture was assessed in vitro. MTT assay, CCK-8 assay, Caspase3/7 assay, assay of cell apoptosis and Celigo wound healing was conducted to evaluate the relationship between circular RNA and the rupture of human intracranial aneurysms.

Results: A total of 13,175 circRNA genes were detected. Among them 63 circRNAs upregulated and 54 circRNAs downregulated significantly in ruptured intracranial aneurysms compared with un-ruptured intracranial aneurysms (p < 0.05 Fold Change > 1.5). Five upregulated circRNAs were selected for further study (hsa_circ_0001947, hsa_circ_0043001, hsa_circ_0064557, hsa_circ_0058514, hsa_circ_0005505). The results of qPCR showed only hsa_circ_0005505 significantly upregulated (p < 0.05). The expression of hsa_circ_0005505 was higher in ruptured intracranial aneurysm tissues. And our in vitro data showed that hsa_circRNA_005505 promotes the proliferation, migration and suppresses the apoptosis of vascular smooth muscle cell.

Conclusion: This study revealed an important role of hsa_circ_0005505 in the proliferation, migration and apoptosis of vascular smooth muscle cell, and indicated that hsa_circ_0005505 may associate with the pathological process of intracranial aneurysms.

Activation of Galanin Receptor 1 with M617 Attenuates Neuronal Apoptosis via ERK/GSK-3β/TIP60 Pathway After Subarachnoid Hemorrhage in Rats

Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease. Neuronal apoptosis plays an important pathological role in early brain injury after SAH. Galanin receptor 1 (GalR1) activation was recently shown to be anti-apoptotic in the setting of ischemic stroke. This study aimed to explore the anti-neuronal apoptosis effect of GalR1 activation after SAH, as well as the underlying mechanisms. GalR1 CRISPR and GalR1 selective agonist, M617, was administered, respectively. Extracellular-signal-regulated kinase (ERK) inhibitor (U0126) and glycogen synthase kinase 3-beta (GSK3-β) CRISPR were administered to investigate the involvement of the ERK/GSK3-β pathway in GalR1-mediated neuroprotection after SAH. Outcome assessments included neurobehavioral tests, western blot, and immunohistochemistry. The results showed that endogenous ligand galanin (Gal) and GalR1 were markedly increased in the ipsilateral brain hemisphere at 12 h and 24 h after SAH. GalR1 were expressed mainly in neurons, but expression was also observed in some astrocytes and microglia. GalR1 CRISPR knockdown exacerbated neurological deficits and neuronal apoptosis 24 h after SAH. Moreover, activation of GalR1 with M617 significantly improved short- and long-term neurological deficits but decreased neuronal apoptosis after SAH. Furthermore, GalR1 activation dysregulated the protein levels of phosphorylated ERK and GSK-3β, but downregulated the phosphorylated Tat-interactive protein 60 (TIP60) and cleaved caspase-3 at 24 h after SAH. GalR1 CRISPR, U0126, and GSK-3β CRISPR abolished the beneficial effects of GalR1 activation at 24 h after SAH in rats. Collectively, the present study demonstrated that activation of GalR1 using M617 attenuated neuronal apoptosis through the ERK/GSK-3β/TIP60 pathway after SAH in rats. GalR1 may serve as a promising therapeutic target for SAH patients.

Circumferential segmental vessel-wall enhancement on black blood MRI in patients referred for the evaluation of vasculopathy

BACKGROUND

High resolution intracranial vessel wall magnetic resonance imaging, or black blood MRI, has recently gained traction as an adjunct to computed tomography angiography, magnetic resonance angiography, and digital subtraction angiography in the characterization of atherosclerosis, vasculitides, and inflammatory changes in the aneurysm wall. However, the occurrence of uniform circumferential segmental arterial vessel wall enhancement (CSWE) in patients without these diagnoses has not previously been studied. The purpose of this study is twofold: 1) to evaluate the prevalence of CSWE in the major intracranial arteries in patients without vasculitides, symptomatic atherosclerosis, or aneurysmal subarachnoid hemorrhage and 2) to determine the association, if any, between such enhancement and risk factors for cerebrovascular atherosclerotic disease.

MATERIALS & METHODS

A retrospective study of vessel wall magnetic resonance imaging examinations was performed to evaluate for CSWE in 26 patients without known vessel wall pathology such as aneurysms or vasculitides and intracranial hemorrhage. Further evaluation of CSWE association with major intracranial atherosclerotic disease risk factors including hypertension, hyperlipidemia, diabetes mellitus and cigarette smoking was performed.

RESULTS AND CONCLUSION

46% of the cohort of patients demonstrated CSWE. Among the patients with CSWE, there was increased prevalence of CSWE in the posterior circulation vasculature with particular predilection to the V4 vertebral artery segments (92%), although there was greater association of anterior circulation CSWE with risk factors for atherosclerosis. Patients with anterior circulation CSWE also demonstrated the most number of segments with CSWE. We therefore propose that CSWE, particularly in the anterior circulation, may portend early atherosclerosis.

Lower risk of subarachnoid haemorrhage in diabetes: a nationwide population-based cohort study

Background and purpose

Diabetes mellitus (DM) is a common metabolic disorder with increased risk of cardiovascular and cerebrovascular complications. However, its relationship with risk of subarachnoid haemorrhage (SAH), the most devastating form of stroke, remains controversial.

Methods

To evaluate the relationship between DM and risk of SAH, we performed a retrospective cohort study using a nationwide, population‐based, health screening database in Korea. We included participants without history of stroke who underwent a nationwide health screening programme between 2003 and 2004. Primary outcome was occurrence of SAH. Participants were followed up until development of SAH or December 2015. Multivariate Cox proportional hazards regression analysis was performed with adjustments for age, sex, systolic blood pressure, total cholesterol, body mass index, physical activity, smoking status, alcohol habit, household income and treatment with antihypertensive agents and statins.

Results

Among 421 768 study participants, prevalence of DM was 9.6%. During a mean follow-up period of 11.6±1.9 years, 1039 patients developed SAH. Presence of DM was significantly associated with decreased risk of SAH (adjusted HR 0.68; 95% CI 0.53 to 0.86; p<0.001). Elevated level of fasting blood glucose was also negatively associated with risk of SAH (adjusted HR per 1 mmol/L increase 0.90; 95% CI 0.86 to 0.95; p<0.001).

Conclusion

DM and elevated level of fasting blood glucose were inversely associated with risk of SAH. Further studies may elucidate the possibly protective, pathophysiological role played by hyperglycaemia in patients at risk of SAH.

Early permanent cerebrospinal fluid diversion in aneurysmal subarachnoid hemorrhage: does a lower rate of nosocomial meningitis outweigh the risk of delayed cerebral vasospasm related morbidity?

Objective: Early permanent cerebrospinal fluid (CSF) diversion for hydrocephalus during the first 2 weeks after aneurysmal subarachnoid hemorrhage (aSAH) shortens the duration of external ventricular drainage (EVD) and reduces EVD-associated infections (EVDAI). The objective of this study was to detect any association with symptomatic delayed cerebral vasospasm (DCVS), or delayed cerebral ischemia (DCI) by the time of hospital discharge. Methods: We used a single-center dataset of aSAH patients who had received a permanent CSF diversion. We compared an 'early group' in which the procedure was performed up to 14 days after the ictus, to a 'late group' in which it was performed from the 15^th day onward. Results: Among 274 consecutive aSAH patients, 39 (14%) had a permanent CSF diversion procedure with a silver-coated EVD. While the blood clot burden was similarly distributed, patients with early permanent CSF diversion (20 out of 39; 51%) had higher levels of consciousness on admission. Early permanent CSF diversion was associated with less colonized catheter, a shorter duration of extracorporeal CSF diversion (OR 0.73, 95%CI 0.58-0.92 per EVD day), and a lower rate of EVDAI (OR 0.08, 95%CI 0.01-0.80). The occurrence of CSF diversion device obstruction, the rate of symptomatic DCVS or detected DCI on computed tomography and the likelihood of a poor outcome at discharge did not differ between the two groups. Discussion: Early permanent CSF diversion lowers the occurrence of catheter colonization and infectious complication without affecting DCVS-related morbidity in good-grade aSAH patients. These findings need confirmation in larger prospective multicenter cohorts. Abbreviations: aSAH: aneurysmal subarachnoid hemorrhage; BNI: Barrow Neurological Institute Scale; CSF: Cerebrospinal fluid; DCVS: Delayed Cerebral Vasospasm; DCI: Delayed Cortical Ischemia; EKNZ: Ethik-Kommission Nordwest Schweiz; EVD: External ventricular drain; EVDAI: External ventricular drain-associated infections; GCS: Glasgow Coma Scale; IRB: Institutional Review Board; IVH: Inraventricular hemorrhage; mRS: Modified Rankin Scale; SOS: Swiss Study of Subarachnoid Hemorrhage Registry; WFNS: World Federation Neurological-Surgeon Scale.

Intermediate surgical outcome in patients suffering poor-grade aneurysmal subarachnoid hemorrhage. A single center experience

BACKGROUND

It is known that patients suffering poor-grade aneurysmal subarachnoid hemorrhage (aSAH) have a dismal prognosis. The importance of early intervention is well established in the pertinent literature. Our aim was to assess the functional outcome and overall survival of these patients undergoing surgical clipping.

MATERIAL AND METHODS

In the current retrospective study we included all consecutive poor-grade patients after spontaneous SAH who presented at our institution over an eight-year period. All participants suffering SAH underwent brain CT angiography (CTA) to identify the source of hemorrhage. We assessed the severity of hemorrhage according to the Fisher grade classification scale. All patients were surgically treated. The functional outcome was evaluated six months after the onset with the Glasgow Outcome Scale. Finally, we performed logistic and Cox regression analyses to identify potential prognostic risk factors.

RESULTS

Our study included twenty-three patients with a mean age of 53 years. Five (22%) patients presented with Hunt and Hess grade IV, and eighteen (78%) with grade V. The mean follow-up was 15.8 months, while the overall mortality rate was 48%. The six-month functional outcome was favorable in 6 (26%) patients. The vast majority of our patients died between the 15^th and the 60^th post-ictal days. We did not identify any statistically significant prognostic factors related to the patient's outcome and/or survival.

CONCLUSIONS

Poor-grade aSAH patients may have a favorable outcome with proper surgical management. Large-scale studies are necessary for accurately outlining the prognosis of this entity, and identifying parameters that could be predictive of outcome.

lncRNA Signature for Predicting Cerebral Vasospasm in Patients with SAH: Implications for Precision Neurosurgery

Subarachnoid hemorrhage (SAH) patients’ surgery is performed to prevent extravasation of blood into the subarachnoid space. Cerebral vasospasm (CVS; narrowing of cerebral arteries) occurs following SAH and represents a major cause of associated mortality and morbidity. To improve postsurgery care of SAH patients and their prognosis, the ability to predict CVS onset is critical. We report a long noncoding RNA (lncRNA) signature to distinguish SAH patients with CVS from SAH patients without CVS. Cerebrospinal fluid (CSF) was obtained from SAH patients without CVS (n = 10) and SAH patients with CVS (n = 10). lncRNAs ZFAS1 and MALAT1 were significantly upregulated (p < 0.05), whereas lncRNAs LINC00261 and LINC01619 were significantly downregulated in SAH patients with CVS (p < 0.05) compared to SAH patients without CVS. We applied this lncRNA signature to retrospectively predict CVS in SAH patients (n = 38 for SAH patients without CVS, and n = 27 for SAH patients with CVS). The 4-lncRNA signature was found to be predictive in >40% of samples and the 2-lncRNA comprising MALAT1 and LINC01619 accurately predicted CVS in ∼90% cases. These results are initial steps toward personalized management of SAH patients in clinics and provide novel CSF biomarkers that can substantially improve the clinical management of SAH patients.

The Role of Transcranial Doppler in Cerebral Vasospasm: A Literature Review

Transcranial Doppler ultrasonography (TCD) is a noninvasive technique used to detect vasospasms following a subarachnoid hemorrhage. While the gold standard to evaluate vasospasms is angiography, this technique is invasive and poses additional risks as compared to TCD. TCD is performed by insonating circle of Willis arteries to measure cerebral flow velocity. TCD allows dynamic monitoring of CBF-V and vessel pulsatility, with a high temporal resolution. It is relatively inexpensive, repeatable, and portable; however, the performance of TCD is highly operator dependent and can be difficult, especially with inadequate acoustic windows. This review summarizes the use of transcranial Doppler ultrasonography (TCD) for the assessment of cerebral vasospasm.

Elucidating the novel biomarker and therapeutic potentials of High-mobility group box 1 in Subarachnoid hemorrhage: A review

Subarachnoid hemorrhage (SAH) frequently arises after an aneurysm in a cerebral artery ruptures, resulting into bleeding as well as clot formation. High-mobility group box 1 (HMGB1) is an extremely preserved, universal protein secreted in the nuclei of all cell varieties. This review explores the biomarker as well as therapeutic potentials of HMBG1 in SAH especially during the occurrence of cerebral vasospasms. Plasma HMGB1 levels have proven to be very useful prognosticators of effective outcome as well as death after SAH. Correspondingly, higher HMGB1 levels in the cerebrospinal fluid (CSF) of SAH patients correlated well with poor outcome; signifying that, CSF level of HMGB1 is a novel predictor of outcome following SAH. Nonetheless, the degree of angiographic vasospasm does not always correlate with the degree of neurological deficits in SAH patients. HMGB1 stimulated cerebral vasospasm, augmented gene as well as protein secretory levels of receptor for advance glycation end product (RAGE) in neurons following SAH; which means that, silencing HMGB1 during SAH could be of therapeutic value. Compounds like resveratrol, glycyrrhizin, rhinacanthin, purpurogallin, 4′-O-β-D-Glucosyl-5-O-Methylvisamminol (4OGOMV) as well as receptor-interacting serine/threonine-protein kinase 3 (RIPK3) gene are capable of interacting with HMGB1 resulting in therapeutic benefits following SAH.

Antioxidant Melatonin: Potential Functions in Improving Cerebral Autoregulation After Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a subtype of stroke with high mortality and morbidity. Impaired cerebral autoregulation following SAH has been reported owing to effects on sympathetic control, endothelial function, myogenic response, and cerebral metabolism. Impaired cerebral autoregulation is associated with early brain injury, cerebral vasospasm/delayed cerebral ischemia, and SAH prognosis. However, few drugs have been reported to improve cerebral autoregulation after SAH. Melatonin is a powerful antioxidant that is effective (easily crosses the blood brain barrier) and safe (tolerated in large doses without toxicity). Theoretically, melatonin may impact the control mechanisms of cerebral autoregulation via antioxidative effects, protection of endothelial cell integrity, suppression of sympathetic nerve activity, increase in nitric oxide bioavailability, mediation of the myogenic response, and amelioration of hypoxemia. Furthermore, melatonin may have a comprehensive effect on cerebral autoregulation. This review discusses the potential effects of melatonin on cerebral autoregulation following SAH, in terms of the association between pharmacological activities and the mechanisms of cerebral autoregulation.

Add-on therapy with traditional Chinese medicine: An efficacious approach for lipid metabolism disorders

Add-on therapy with traditional Chinese medicine (TCM) has been extensively researched in the intractable diseases, such as asthma, cancer, and Alzheimer's disease. As an entirely new concept, add-on therapy of TCM has been also used to prevent and treat hyperlipidemia via lowering cholesterol level. However, the efficacy of add-on therapy with TCM for mediating lipid metabolism disorders remains controversial. In this review, we summarize and provide strong evidence that add-on therapy of TCM as a novel approach is efficacious and safe for hyperlipidemia associated diseases based on the mediation of lipid metabolism disorders.

Use of levosimendan in the treatment of cerebral vascular vasospasm: a case study

Despite the progress in the management of cerebral arterial aneurysms, subarachnoid hemorrhage (SAH) remains the major cause of neurological disability. While SAH-related deaths usually occur as a result of brain impairment due to hemorrhage, permanent neurological deficits are caused by cerebral ischemia due to edema and spasm of cerebral arteries. Additionally, ~20%-30% of patients with SAH develop secondary cardiomyopathy; this phenomenon is known as neurogenic stress cardiomyopathy (NSC), which is associated with increased mortality and poor long-term prognosis. Levosimendan is a new inotropic drug that causes calcium sensitization of troponin C, thus increasing contraction force of myofilaments. The drug also causes opening of ATP-dependent potassium channels in vascular smooth muscles, which results in dilatation of veins and arteries, including cerebral arteries. To date, there have been several reports of levosimendan application in patients with SAH and neurogenic stress cardiomyopathy, and the effect of the drug on vasospasm has been previously advocated. This paper presents a case report of a 57-year-old patient with massive SAH, where levosimendan was used for reducing vasospasm.

Continuous infusion of low-dose unfractionated heparin after aneurysmal subarachnoid hemorrhage: a preliminary study of cognitive outcomes

OBJECTIVE

Cognitive dysfunction occurs in up to 70% of aneurysmal subarachnoid hemorrhage (aSAH) survivors. Low-dose intravenous heparin (LDIVH) infusion using the Maryland protocol was recently shown to reduce clinical vasospasm and vasospasm-related infarction. In this study, the Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive changes in aSAH patients treated with the Maryland LDIVH protocol compared with controls.

METHODS

A retrospective analysis of all patients treated for aSAH between July 2009 and April 2014 was conducted. Beginning in 2012, aSAH patients were treated with LDIVH in the postprocedural period. The MoCA was administered to all aSAH survivors prospectively during routine follow-up visits, at least 3 months after aSAH, by trained staff blinded to treatment status. Mean MoCA scores were compared between groups, and regression analyses were performed for relevant factors.

RESULTS

No significant differences in baseline characteristics were observed between groups. The mean MoCA score for the LDIVH group (n = 25) was 26.4 compared with 22.7 in controls (n = 22) (p = 0.013). Serious cognitive impairment (MoCA ≤ 20) was observed in 32% of controls compared with 0% in the LDIVH group (p = 0.008). Linear regression analysis demonstrated that only LDIVH was associated with a positive influence on MoCA scores (β = 3.68, p =0.019), whereas anterior communicating artery aneurysms and fevers were negatively associated with MoCA scores. Multivariable linear regression analysis resulted in all 3 factors maintaining significance. There were no treatment complications.

CONCLUSIONS

This preliminary study suggests that the Maryland LDIVH protocol may improve cognitive outcomes in aSAH patients. A randomized controlled trial is needed to determine the safety and potential benefit of unfractionated heparin in aSAH patients.

A Comparison of Pathophysiology in Humans and Rodent Models of Subarachnoid Hemorrhage

Non-traumatic subarachnoid hemorrhage (SAH) affects an estimated 30,000 people each year in the United States, with an overall mortality of ~30%. Most cases of SAH result from a ruptured intracranial aneurysm, require long hospital stays, and result in significant disability and high fatality. Early brain injury (EBI) and delayed cerebral vasospasm (CV) have been implicated as leading causes of morbidity and mortality in these patients, necessitating intense focus on developing preclinical animal models that replicate clinical SAH complete with delayed CV. Despite the variety of animal models currently available, translation of findings from rodent models to clinical trials has proven especially difficult. While the explanation for this lack of translation is unclear, possibilities include the lack of standardized practices and poor replication of human pathophysiology, such as delayed cerebral vasospasm and ischemia, in rodent models of SAH. In this review, we summarize the different approaches to simulating SAH in rodents, in particular elucidating the key pathophysiology of the various methods and models. Ultimately, we suggest the development of standardized model of rodent SAH that better replicates human pathophysiology for moving forward with translational research.

Hemolyzed Blood Elicits a Calcium Antagonist and High CO2 Reversible Constriction via Elevation of [Ca2+]i in Isolated Cerebral Arteries

During acute subarachnoid hemorrhage, blood is hemolyzed, which is followed by a significant cerebrovascular spasm resulting in a serious clinical condition. Interestingly, however, the direct vasomotor effect of perivascular hemolyzed blood (HB) has not yet been characterized, preventing the assessment of contribution of vasoconstrictor mechanisms deriving from brain tissue and/or blood and development of possible treatments. We hypothesized that perivascular HB reduces the diameter of the cerebral arteries (i.e., basilar artery [BA]; middle cerebral artery [MCA]) by elevating vascular tissue [Ca²⁺]_i level. Vasomotor responses were measured by videomicroscopy and intracellular Ca²⁺ by the Fura2-AM ratiometric method. Adding HB to the vessel chamber reduced the diameter significantly (BA: from 264 ± 7 to 164 ± 11 μm; MCA: from 185 ± 15 to 155 ± 14 μm), which was reversed to control level by wash-out of HB. Potassium chloride (KCl), HB, serum, hemolyzed red blood cell (RBC), plasma, and platelet suspension (PLTs) elicited significant constrictions of isolated basilar arteries. There was a significant increase in K⁺ concentration in hemolyzed HB (7.02 ± 0.22 mmol/L) compared to Krebs' solution (6.20 ± 0.01 mmol/L). Before HB, acetylcholine (ACh), sodium-nitroprussid (SNP), nifedipin, and CO₂ elicited substantial dilations in cerebral arteries. In contrast, in the presence of HB dilations to ACh, SNP decreased, but not to nifedipine and CO₂. After washout of HB, nitric oxide-mediated dilations remained significantly reduced compared to control. HB significantly increased the ratiometric Ca signal, which returned to control level after washout. In conclusion, perivascular hemolyzed blood elicits significant-nifedipine and high CO₂ reversible-constrictions of isolated BAs and MCAs, primarily by increasing intracellular Ca²⁺, findings that can contribute to the refinement of local treatment of subarachnoid hemorrhage.

Molecular mechanisms and cell signaling of 20-hydroxyeicosatetraenoic acid in vascular pathophysiology

Cytochrome P450s enzymes catalyze the metabolism of arachidonic acid to epoxyeicosatrienoic acids (EETs), dihydroxyeicosatetraenoic acid and hydroxyeicosatetraeonic acid (HETEs). 20-HETE is a vasoconstrictor that depolarizes vascular smooth muscle cells by blocking K+ channels. EETs serve as endothelial derived hyperpolarizing factors. Inhibition of the formation of 20-HETE impairs the myogenic response and autoregulation of renal and cerebral blood flow. Changes in the formation of EETs and 20-HETE have been reported in hypertension and drugs that target these pathways alter blood pressure in animal models. Sequence variants in CYP4A11 and CYP4F2 that produce 20-HETE, UDP-glucuronosyl transferase involved in the biotransformation of 20-HETE and soluble epoxide hydrolase that inactivates EETs are associated with hypertension in human studies. 20-HETE contributes to the regulation of vascular hypertrophy, restenosis, angiogenesis and inflammation. It also promotes endothelial dysfunction and contributes to cerebral vasospasm and ischemia-reperfusion injury in the brain, kidney and heart. This review will focus on the role of 20-HETE in vascular dysfunction, inflammation, ischemic and hemorrhagic stroke and cardiac and renal ischemia reperfusion injury.

A Phase I proof-of-concept and safety trial of sildenafil to treat cerebral vasospasm following subarachnoid hemorrhage

OBJECTIVE

Studies show that phosphodiesterase-V (PDE-V) inhibition reduces cerebral vasospasm (CVS) and improves outcomes after experimental subarachnoid hemorrhage (SAH). This study was performed to investigate the safety and effect of sildenafil (an FDA-approved PDE-V inhibitor) on angiographic CVS in SAH patients.

METHODS

A2-phase, prospective, nonrandomized, human trial was implemented. Subarachnoid hemorrhage patients underwent angiography on Day 7 to assess for CVS. Those with CVS were given 10 mg of intravenous sildenafil in the first phase of the study and 30 mg in the second phase. In both, angiography was repeated 30 minutes after infusion. Safety was assessed by monitoring neurological examination findings and vital signs and for the development of adverse reactions. For angiographic assessment, in a blinded fashion, pre- and post-sildenafil images were graded as "improvement" or "no improvement" in CVS. Unblinded measurements were made between pre- and post-sildenafil angiograms.

RESULTS

Twelve patients received sildenafil; 5 patients received 10 mg and 7 received 30 mg. There were no adverse reactions. There was no adverse effect on heart rate or intracranial pressure. Sildenafil resulted in a transient decline in mean arterial pressure, an average of 17% with a return to baseline in an average of 18 minutes. Eight patients (67%) were found to have a positive angiographic response to sildenafil, 3 (60%) in the low-dose group and 5 (71%) in the high-dose group. The largest degree of vessel dilation was an average of 0.8 mm (range 0-2.1 mm). This corresponded to an average percentage increase in vessel diameter of 62% (range 0%-200%).

CONCLUSIONS

The results from this Phase I safety and proof-of-concept trial assessing the use of intravenous sildenafil in patients with CVS show that sildenafil is safe and well tolerated in the setting of SAH. Furthermore, the angiographic data suggest that sildenafil has a positive impact on human CVS.

[Intracranial aneurysms and their clinical and genetic behaviour]

BACKGROUND

Intracranial aneurysms are abnormal dilations of the cerebral arteries of unknown origin. However, some genes have been linked to their formation, as in the case of NOS3 gene which encodes the endothelial nitric oxide synthase responsible for producing nitric oxide. Several polymorphisms in this gene, in association with a variable number tandem repeat located in intron 4 from eNOS4 gene, can influence the formation of aneurysms. Therefore, the purpose of this study is to determine the genotype frequencies of eNOS3 and eNOS4 genes, and their relationship with intracranial aneurysms.

MATERIAL AND METHODS

A prospective case-control study was performed on 79 cases with ruptured intracranial aneurysm and 93 healthy controls. DNA was obtained from all subjects for the study of the eNOS3 and eNOS4 genes by molecular techniques.

RESULTS

The GG genotype of eNOS3 gene showed the largest number of patients (n=29) with a large aneurysm. While the intracranial aneurysms of medium size were found in a higher percentage (50%) in patients with genotype GT. In terms of patient outcomes, it was observed that those with genotype GG had the highest percentage (43.13%) recovery, compared to genotype GT (27.27%).

CONCLUSIONS

The present study shows that there is a tendency of an association between genotypes of eNOS3 gene with the mean size of the aneurysm, as well as clinical sequelae of the disease in patients with intracranial aneurysms.

Molsidomine for the prevention of vasospasm-related delayed ischemic neurological deficits and delayed brain infarction and the improvement of clinical outcome after subarachnoid hemorrhage: a single-center clinical observational study

OBJECT Delayed ischemic neurological deficits (DINDs) and cerebral vasospasm (CVS) are responsible fora poor outcome in patients with aneurysmal subarachnoid hemorrhage (SAH), most likely because of a decreased availability of nitric oxide (NO) in the cerebral microcirculation. In this study, the authors examined the effects of treatment with the NO donor molsidomine with regard to decreasing the incidence of spasm-related delayed brain infarctions and improving clinical outcome in patients with SAH. METHODS Seventy-four patients with spontaneous aneurysmal SAH were included in this post hoc analysis. Twenty-nine patients with SAH and proven CVS received molsidomine in addition to oral or intravenous nimodipine. Control groups consisted of 25 SAH patients with proven vasospasm and 20 SAH patients without. These patients received nimodipine therapy alone. Cranial computed tomography (CCT) before and after treatment was analyzed for CVS-related infarcts. A modified National Institutes of Health Stroke Scale (mNIHSS) and the modified Rankin Scale (mRS) were used to assess outcomes at a 3-month clinical follow-up. RESULTS Four of the 29 (13.8%) patients receiving molsidomine plus nimodipine and 22 of the 45 (48%) patients receiving nimodipine therapy alone developed vasospasm-associated brain infarcts (p < 0.01). Follow-up revealed a median mNIHSS score of 3.0 and a median mRS score of 2.5 in the molsidomine group compared with scores of 11.5 and 5.0, respectively, in the nimodipine group with CVS (p < 0.001). One patient in the molsidomine treatment group died, and 12 patients in the standard care group died (p < 0.01). CONCLUSIONS In this post hoc analysis, patients with CVS who were treated with intravenous molsidomine had a significant improvement in clinical outcome and less cerebral infarction. Molsidomine offers a promising therapeutic option in patients with severe SAH and CVS and should be assessed in a prospective study.

The efficacy and safety of acupuncture for cerebral vasospasm after subarachnoid hemorrhage: study protocol for a randomized controlled trial

Background

Subarachnoid hemorrhage (SAH) is a neurological disease with a high mortality rate. Several serious complications frequently arise after successful surgery for this condition. Cerebral vasospasm, one such complication, occurs in 50 to 70% of SAH patients. These patients suffer neurological symptoms known as delayed ischemic neurological deficit (DIND); however, the effect of treatment of vasospasm is limited. The major pathogenesis of cerebral vasospasm is the reduction of nitric oxide (NO) and activation of vasoconstrictors. Acupuncture is known to increase the production and activity of vascular endothelial cell-derived NO and improve endothelium-dependent vasodilatation. A preliminary retrospective case study to investigate the ability of acupuncture to prevent the occurrence of cerebral vasospasm has been conducted. However, no randomized, controlled clinical trials have been carried out to evaluate the efficacy of acupuncture for cerebral vasospasm.

Methods/Design

This trial will be a single-center, randomized, placebo-controlled, parallel group, patient-assessor-blinded clinical trial. A total of 80 patients with SAH will be randomized into two groups: a study group given acupuncture, electroacupuncture, and intradermal acupuncture, and a control group given mock transcutaneous electrical nerve stimulation and sham intradermal acupuncture. Intervention will start within 96 h after SAH, and a total of 12 sessions will be performed during a 2-week period. The primary outcome measure will be the occurrence of DIND, and the secondary outcomes will be vasospasm as measured by cerebral angiography, transcranial Doppler, clinical symptoms, vasospasm-related infarcts, NO and endothelin-1 plasma levels, mortality, and modified Rankin Scale scores.

Discussion

This trial will examine the efficacy and safety of acupuncture for cerebral vasospasm after SAH. The placebo effect will be excluded and the mechanism of action of the treatments will be evaluated through blood testing.

Trial registration

ClinicalTrials.gov NCT02275949, Registration date: 26 October 2014.

SAH-induced MMP activation and K V current suppression is mediated via both ROS-dependent and ROS-independent mechanisms

Voltage-gated potassium (K V) channels regulate cerebral artery tone and have been implicated in subarachnoid hemorrhage (SAH)-induced pathologies. Here, we examined whether matrix metalloprotease (MMP) activation contributes to SAH-induced K V current suppression and cerebral artery constriction via activation of epidermal growth factor receptors (EGFRs). Using patch clamp electrophysiology, we observed that K V currents were selectively decreased in cerebral artery myocytes isolated from SAH model rabbits. Consistent with involvement of enhanced MMP and EGFR activity in SAH-induced K V current suppression, we found that: (1) oxyhemoglobin (OxyHb) and/or the exogenous EGFR ligand, heparin-binding EGF-like growth factor (HB-EGF), failed to induce further K V current suppression after SAH and (2) gelatin zymography detected significantly higher MMP-2 activity after SAH. The removal of reactive oxygen species (ROS) by combined treatment with superoxide dismutase (SOD) and catalase partially inhibited OxyHb-induced K V current suppression. However, these agents had little effect on OxyHb-induced MMP-2 activation. Interestingly, in the presence of a broad-spectrum MMP inhibitor (GM6001), OxyHb failed to cause K V current suppression. These data suggest that OxyHb suppresses K V currents through both ROS-dependent and ROS-independent pathways involving MMP activation. The ROS-independent pathway involves activation of MMP-2, whereas the ROS-dependent pathway involves activation of a second unidentified MMP or ADAM (a disintegrin and metalloprotease domain).

Vasospasm in cerebral inflammation

All forms of cerebral inflammation as found in bacterial meningitis, cerebral malaria, brain injury, and subarachnoid haemorrhage have been associated with vasospasm of cerebral arteries and arterioles. Vasospasm has been associated with permanent neurological deficits and death in subarachnoid haemorrhage and bacterial meningitis. Increased levels of interleukin-1 may be involved in vasospasm through calcium dependent and independent activation of the myosin light chain kinase and release of the vasoconstrictor endothelin-1. Another key factor in the pathogenesis of cerebral arterial vasospasm may be the reduced bioavailability of the vasodilator nitric oxide. Therapeutic trials in vasospasm related to inflammation in subarachnoid haemorrhage in humans showed a reduction of vasospasm through calcium antagonists, endothelin receptor antagonists, statins, and plasminogen activators. Combination of therapeutic modalities addressing calcium dependent and independent vasospasm, the underlying inflammation, and depletion of nitric oxide simultaneously merit further study in all conditions with cerebral inflammation in double blind randomised placebo controlled trials. Auxiliary treatment with these agents may be able to reduce ischemic brain injury associated with neurological deficits and increased mortality.

The clinical profile, management, and overall outcome of aneurysmal subarachnoid hemorrhage at the neurosurgical unit of a tertiary care center in India

Background and Purpose:

Several studies report good outcomes in selected patients of aneurysmal subarachnoid hemorrhage (aSAH). The purpose of our study is to project the clinical characteristics, management, and overall outcome of patients with aSAH presenting to a tertiary care center in India.

Materials and Methods:

A prospective study was conducted over a period of 10 months and all patients presenting with aSAH were studied. Patients presenting in all grades and managed with any type of intervention or managed conservatively were included to characterize their clinical and radiological profile at admission, during management, and at discharge. Outcome was assessed with the Glasgow Outcome Score (GOS) at 3 months follow-up.

Results:

Out of the 482 patients [mean age: 51.3 (±13.5); M: F = 1:1], 330 patients were fit to be taken up for intervention of the ruptured aneurysm, while 152 patients were unfit for any intervention. At 3 months follow-up, good outcome (GOS 4 and 5) was observed in 159 (33%), poor outcome (GOS 2 and 3) in 53 (11%), and death in 219 (45.4%) patients, while 51 patients (10.6%) were lost to follow-up. Most (95%) of the patients in the non-intervention group expired, and hence the high mortality rate, as we have analyzed the results of all patients of all grades, regardless of the treatment given. The predictors of poor outcome (GOS 1, 2, and 3) at 3 months follow-up, using multinomial regression model, were: World Federation of Neurological Surgeons (WFNS) grade IV and V (at admission and after adequate resuscitation) [odds ratio (OR): 35.1, 95% confidence interval (CI): 10.8-114.7] and presence of hypertension as a co-morbid illness [OR: 2.7, 95% CI: 1.6-5.6]. All patients showing acute infarction on computed tomography scan at presentation had a poor outcome.

Conclusions:

Despite recent advances in the treatment of patients with aSAH, the morbidity and mortality rates have failed to improve significantly in unselected patients and natural cohorts. This may be attributed to the natural history of aSAH, and calls for new strategies to diagnose and treat such patients before the catastrophe strikes.

Alteration of basilar artery rho-kinase and soluble guanylyl cyclase protein expression in a rat model of cerebral vasospasm following subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The vasoconstrictor endothelin-1 (ET-1) has been implicated in the pathogenesis of cerebral vasospasm following subarachnoid hemorrhage (SAH). Previous results showed that CGS 26303, an endothelin converting enzyme (ECE) inhibitor, effectively prevented and reversed arterial narrowing in animal models of SAH. In the present study, we assessed the effect of CGS 26303 on neurological deficits in SAH rats. The involvement of vasoactive pathways downstream of ET-1 signaling in SAH was also investigated.

METHODS

Sprague-Dawley rats were divided into five groups (n = 6/group): (1) normal control, (2) SAH, (3) SAH+vehicle, (4) SAH+CGS 26303 (prevention), and (5) SAH+CGS 26303 (reversal). SAH was induced by injecting autologous blood into cisterna magna. CGS 26303 (10 mg/kg) was injected intravenously at 1 and 24 hr after the initiation of SAH in the prevention and reversal protocols, respectively. Behavioral changes were assessed at 48 hr after SAH. Protein expression was analyzed by Western blots.

RESULTS

Deficits in motor function were obvious in the SAH rats, and CGS 26303 significantly improved the rate of paraplegia. Expressions of rho-kinase-II and membrane-bound protein kinase C- δ and rhoA were significantly increased, while those of soluble guanylyl cyclase α 1 and β 1 as well as protein kinase G were significantly decreased in the basilar artery of SAH rats. Treatment with CGS 26303 nearly normalized these effects.

CONCLUSIONS

These results demonstrate that the rhoA/rho-kinase and sGC/cGMP/PKG pathways play pivotal roles in cerebral vasospasm after SAH. It also shows that ECE inhibition is an effective strategy for the treatment of this disease.

Sampling of CSF via the Cisterna Magna and Blood Collection via the Heart Affects Brain Water Content in a Rat SAH Model

The aim of this study was to evaluate whether sampling of cerebrospinal fluid (CSF) via the cisterna magna and of blood via the heart affects brain water content in a rat subarachnoid hemorrhage (SAH) model. Twenty-nine animals were divided into four groups: sham-operated group with sampling of CSF and blood (Sham S+), sham-operated group without sampling of CSF and blood (Sham S-), SAH group with sampling of CSF and blood (SAH S+), and SAH without sampling of CSF and blood (SAH S-). SAH was induced via endovascular perforation of the left internal carotid artery bifurcation. Cerebrospinal fluid via the cisterna magna and blood via cardiac puncture was collected in the Sham S+ and SAH S+ groups before killing the animals for brain water content measurements. Left hemisphere brain water content was significantly higher in the SAH S- group compared with the Sham S- group (p< 0.05) and in Sham S+ group compared with the Sham S- group (p<0.05). There was no significant difference in brain water content of the left hemisphere between the SAH S+ and Sham S+ groups (p=NS). There was no significant difference in brain water content in other parts of brains. Sampling of CSF and blood affected brain water content in Sham animals and therefore it is not accurate to use these values from Sham animals for comparison with SAH animals.

Novel effects of edaravone on human brain microvascular endothelial cells revealed by a proteomic approach

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a free radical scavenger used for acute ischemic stroke. However, it is not known whether edaravone works only as a free radical scavenger or possess other pharmacological actions. Therefore, we elucidated the effects of edaravone on human brain microvascular endothelial cells (HBMECs) by 2 dimensional fluorescence difference gel electrophoresis (2D-DIGE). We found 38 protein spots the intensity of which was significantly altered 1.3 fold on average (p< 0.05) by the edaravone treatment and successfully identified 17 proteins of those. Four of those 17 proteins were cytoskeleton proteins or cytoskeleton-regulating proteins. Therefore, we subsequently investigated the change of size and shape of the cells, the actin network, and the tight junction of HBMEC by immunocytochemistry. As a result, most edaravone-treated HBMECs became larger and rounder compared with those that were not treated. Furthermore, edaravone-treated HBMECs formed gathering zona occludens (ZO)-1, a tight junction protein, along the junction of the cells. In addition, we found that edaravone suppressed interleukin (IL)-1β-induced secretion of monocyte chemoattractant protein-1 (MCP-1), which was reported to increase cell permeability. We found a novel function of edaravone is the promotion of tight junction formations of vascular endothelial cells partly via the down-regulation of MCP-1 secretion. These data provide fundamental and useful information in the clinical use of edaravone in patients with cerebral vascular diseases.

Evidence that 20-HETE contributes to the development of acute and delayed cerebral vasospasm

Recent studies have indicated that arachidonic acid (AA) is metabolized by the cytochrome P450 4A (CYP4A) enzymes in cerebral arteries to produce 20-hydroxyeicosatetraenoic acid (20-HETE) and that this compound has effects on cerebral vascular tone that mimic those seen following subarachnoid hemorrhage (SAH). In this regard, 20-HETE is a potent constrictor of cerebral arteries that decreases the open state probability of Ca(2+)-activated K(+) channels through activation of protein kinase C (PKC). It increases the sensitivity of the contractile apparatus to Ca(2+) by activating PKC and rho kinase. The formation of 20-HETE is stimulated by angiotensin II (AII), endothelin, adenosine triphosphate (ATP) and serotonin, and inhibited by NO, CO and superoxide radicals. Inhibitors of the formation of 20-HETE block the myogenic response of cerebral arterioles to elevations in transmural pressure in vitro and autoregulation of cerebral blood flow (CBF) in vivo. 20-HETE also plays an important role in modulating the cerebral vascular responses to vasodilators (NO and CO) and vasoconstrictors (AII, endothelin, serotonin). Recent studies have indicated that the levels of 20-HETE in cerebrospinal fluid (CSF) increase in rats, dogs and human patients following SAH and that inhibitors of the synthesis of 20-HETE prevent the acute fall in CBF in rats and reverse delayed vasospasm in both dogs and rats. This review examines the evidence that an elevation in the production of 20-HETE contributes to the initial fall in CBF following SAH and the later development of delayed vasospasm.

Effect of melatonin on cerebral vasospasm following experimental subarachnoid hemorrhage

OBJECT

The current study was undertaken to determine whether melatonin therapy reverses vasospasm and prevents apoptosis by inhibiting lipid peroxidation in an experimental subarachnoid hemorrhage (SAH) model.

MATERIALS AND METHODS

The rabbits were divided into four groups as follows: Group 1, SAH + melatonin (5 mg/kg/i.p. BID) simultaneously with SAH (n = 6); Group 2, SAH + melatonin (5 mg/kg/i.p. BID) treated 2 hours after SAH (n = 6); Group 3, control group (n = 4); Group 4, SAH only (n = 6). Light microscopic examinations of the basilar arteries were performed to demonstrate the pathophysiological changes of the arterial wall with hematoxylin- eosin. Apoptosis: Immunohistology using the ApopTag Peroxidase In Situ Apoptosis Detection Kit was used to demonstrate apoptosis in a cross section of basilary arteries. Apoptotic index was calculated as the number of the immunoreactive nuclei per total number of endothelial cells, and expressed as a percentage.

RESULTS

The results of measurements of diameters of the vessels between groups were significantly different (p = 0.028). While basilar arteries of the SAH only group showed 57% constriction, Groups 1 and 2 were calculated as 33 and 26% constriction, respectively, compared with the control group (p < 0.05). And also Groups 1 and 2 showed significant protection of apoptosis compared with Group 4. The difference between the four groups was tested by Kruskal-Wallis test and the significance between the two groups was tested by Mann- Whitney U-test.

CONCLUSION

Melatonin with its strong antioxidant effect can prevent SAH-induced vasospasm and apoptosis of endothelial cells of vessels.

Mechanisms of acute brain injury after subarachnoid hemorrhage

Brain injury after subarachnoid hemorrhage (SAH) is a biphasic event with an acute ischemic insult at the time of the initial bleed and secondary events such as cerebral vasospasm 3 to 7 days later. Although much has been learned about the delayed effects of SAH, less is known about the mechanisms of acute SAH-induced injury. Distribution of blood in the subarachnoid space, elevation of intracranial pressure, reduced cerebral perfusion and cerebral blood flow (CBF) initiates the acute injury cascade. Together they lead to direct microvascular injury, plugging of vessels and release of vasoactive substances by platelet aggregates, alterations in the nitric oxide (NO)/nitric oxide synthase (NOS) pathways and lipid peroxidation. This review will summarize some of these mechanisms that contribute to acute cerebral injury after SAH.

Relationship between plasma high mobility group box-1 protein levels and clinical outcomes of aneurysmal subarachnoid hemorrhage

Background

High-mobility group box 1 (HMGB1), originally described as a nuclear protein that binds to and modifies DNA, is now regarded as a central mediator of inflammation by acting as a cytokine. However, the association of HMGB1 in the peripheral blood with disease outcome and cerebrovasospasm has not been examined in patients with aneurysmal subarachnoid hemorrhage.

Methods

In this study, 303 consecutive patients were included. Upon admission, plasma HMGB1 levels were measured by ELISA. The end points were mortality after 1 year, in-hospital mortality, cerebrovasospasm and poor functional outcome (Glasgow Outcome Scale score of 1 to 3) after 1 year.

Results

Upon admission, the plasma HMGB1 level in patients was statistically significantly higher than that in healthy controls. A multivariate analysis showed that the plasma HMGB1 level was an independent predictor of poor functional outcome and mortality after 1 year, in-hospital mortality and cerebrovasospasm. A receiver operating characteristic curve showed that plasma HMGB1 level on admission statistically significantly predicted poor functional outcome and mortality after 1 year, in-hospital mortality and cerebrovasospasm of patients. The area under the curve of the HMGB1 concentration was similar to those of World Federation of Neurological Surgeons (WFNS) score and modified Fisher score for the prediction of poor functional outcome and mortality after 1 year, and in-hospital mortality, but not for the prediction of cerebrovasospasm. In a combined logistic-regression model, HMGB1 improved the area under the curve of WFNS score and modified Fisher score for the prediction of poor functional outcome after 1 year, but not for the prediction of mortality after 1 year, in-hospital mortality, or cerebrovasospasm.

Conclusions

HMGB1 level is a useful, complementary tool to predict functional outcome and mortality after aneurysmal subarachnoid hemorrhage. However, HMGB1 determination does not add to the accuracy of prediction of the clinical outcomes.

The importance of early brain injury after subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a medical emergency that accounts for 5% of all stroke cases. Individuals affected are typically in the prime of their lives (mean age 50 years). Approximately 12% of patients die before receiving medical attention, 33% within 48 h and 50% within 30 days of aSAH. Of the survivors 50% suffer from permanent disability with an estimated lifetime cost more than double that of an ischemic stroke. Traditionally, spasm that develops in large cerebral arteries 3-7 days after aneurysm rupture is considered the most important determinant of brain injury and outcome after aSAH. However, recent studies show that prevention of delayed vasospasm does not improve outcome in aSAH patients. This finding has finally brought in focus the influence of early brain injury on outcome of aSAH. A substantial amount of evidence indicates that brain injury begins at the aneurysm rupture, evolves with time and plays an important role in patients' outcome. In this manuscript we review early brain injury after aSAH. Due to the early nature, most of the information on this injury comes from animals and few only from autopsy of patients who died within days after aSAH. Consequently, we began with a review of animal models of early brain injury, next we review the mechanisms of brain injury according to the sequence of their temporal appearance and finally we discuss the failure of clinical translation of therapies successful in animal models of aSAH.

Detection of copeptin in peripheral blood of patients with aneurysmal subarachnoid hemorrhage

Introduction

Copeptin has been proposed as a prognostic marker in acute illness. This study investigated the ability of copeptin to predict the disease outcome and cerebrovasospasm in the patients with aneurysmal subarachnoid hemorrhage.

Methods

In this retrospective study, 303 consecutive patients were included. Upon admission, plasma copeptin levels were measured by enzyme-linked immunosorbent assay. The end points were mortality after 1 year, in-hospital mortality, cerebrovasospasm and poor functional outcome (Glasgow Outcome Scale score of 1-3) after 1 year.

Results

Upon admission, plasma copeptin level in patients was statistically significantly higher than that in healthy controls. A multivariate analysis showed that plasma copeptin level was an independent predictor of poor functional outcome and mortality after 1 year, in-hospital mortality and cerebrovasospasm. A receiver operating characteristic curve showed that plasma copeptin level on admission predicted poor functional outcome and mortality after 1 year, in-hospital mortality and cerebrovasospasm of patients statistically significantly. The area under curve of the copeptin concentration was similar to those of World Federation of Neurological Surgeons (WFNS) score and modified Fisher score for the prediction of poor functional outcome and mortality after 1 year, and in-hospital mortality, but not for the prediction of cerebrovasospasm. In a combined logistic-regression model, copeptin improved the area under curve of WFNS score and modified Fisher score for the prediction of poor functional outcome after 1 year, but not for the prediction of mortality after 1 year, in-hospital mortality, and cerebrovasospasm.

Conclusions

Copeptin level is a useful, complementary tool to predict functional outcome and mortality after aneurysmal subarachnoid hemorrhage.

Late ophthalmological assessment of patients with subarachnoid hemorrhage and clipping of cerebral aneurysm

PURPOSE

To estimate prospectively late ocular manifestations in patients after aneurysmal subarachnoid hemorrhage (SAH) treated with aneurysm clipping.

METHODS

Forty-six patients (12 men and 34 women), 23-69 years of age, were included in this study. A conventional ophthalmological examination, visual evoked potentials (VEPs), and static perimetry were performed on all patients. The mean interval between the onset of SAH and the aforementioned examination was 1.9 ± 1.3 years (range 0.5-5 years). The following were compared between patients with affected and non-affected visual fields as well as between those with normal and abnormal VEPs: sex, age, time from SAH to surgery, Hunt and Hess scale, Glasgow Coma Scale, Glasgow Outcome Scale, grading of SAH according to the Fisher scale, and the size and site of aneurysm.

RESULTS

Visual field defects were found in 23 patients (50%). In all of these patients, both eyes were affected. The most frequent type of visual field defects were: constricted field (47.8%), multiple peripheral foci (26.1%), and superior field defect (17.4%). There was no significant relationship between the analyzed factors and the occurrence of visual field defects, although statistical significance was almost observed in respect to the Fisher scale (p = 0.055). Deterioration in VEPs was observed in nine patients (19.6%). In the group of patients with abnormal VEPs, the time from onset of SAH to surgery was 2.6 ± 1.8 days, whereas in the group of patients with normal VEPs this time amounted to 6.4 ± 2.4 days (p = 0.02). In patients with no changes in VEPs, the mean Fisher score was significantly higher than in the group with abnormal VEPs (2.8 ± 0.6 vs 2.0 ± 0.4 respectively, p = 0.04).

CONCLUSION

Visual field defects and VEP deterioration are frequent late ocular manifestations of SAH treated with aneurysm clipping. Damage to the visual pathway correlates with the severity of SAH and timing of aneurysmal surgery.

Pituitary dysfunction following traumatic brain injury or subarachnoid haemorrhage - in "Endocrine Management in the Intensive Care Unit"

Traumatic brain injury and subarachnoid haemorrhage are important causes of morbidity and mortality in the developed world. There is a large body of evidence that demonstrates that both conditions may adversely affect pituitary function in both the acute and chronic phases of recovery. Diagnosis of hypopituitarism and accurate treatment of pituitary disorders offers the opportunity to improve mortality and outcome in both traumatic brain injury and subarachnoid haemorrhage. In this article, we will review the history and pathophysiology of pituitary function in the acute phase following traumatic brain injury and subarachnoid haemorrhage, and we will discuss in detail three key aspects of pituitary dysfunction which occur in the early course of TBI; acute cortisol deficiency, diabetes insipidus and SIAD.

Impaired vascular responses of insulin-resistant rats after mild subarachnoid hemorrhage

Insulin resistance (IR) impairs cerebrovascular responses to several stimuli in Zucker obese (ZO) rats. However, cerebral artery responses after subarachnoid hemorrhage (SAH) have not been described in IR. We hypothesized that IR worsens vascular reactions after a mild SAH. Hemolyzed blood (300 μl) or saline was infused (10 μl/min) into the cisterna magna of 11-13-wk-old ZO (n = 25) and Zucker lean (ZL) rats (n = 25). One day later, dilator responses of the basilar artery (BA) and its side branch (BA-Br) to acetylcholine (ACh, 10(-6) M), cromakalim (10(-7) M, 10(-6) M), and sodium nitroprusside (10(-7) M) were recorded with intravital videomicroscopy. The baseline diameter of the BA was increased both in the ZO and ZL rats 24 h after the hemolysate injection. Saline-injected ZO animals showed reduced dilation to ACh (BA = 9 ± 3 vs. 22 ± 4%; and BA-Br = 23 ± 5 vs. 37 ± 7%) compared with ZL rats. Hemolysate injection blunted the response to ACh in both the ZO (BA = 4 ± 2%; and BA-Br = 12 ± 3%) and ZL (BA = 7 ± 2%; and BA-Br = 11 ± 3%) rats. Cromakalim (10(-6) M)-induced dilation was significantly reduced in the hemolysate-injected ZO animals compared with the saline control (BA = 13 ± 3 vs. 26 ± 5%; and BA-Br = 28 ± 8 vs. 44 ± 9%) and in the hemolysate-injected ZL rats compared with their saline control (BA = 24 ± 4 vs. 32 ± 4%; but not BA-Br = 39 ± 6 vs. 59 ± 9%). No significant difference in sodium nitroprusside reactivity was observed. Western blot analysis of the BA showed a lower baseline level of neuronal nitric oxide synthase expression and an enhanced cyclooxygenase-2 level in the hemolysate-injected ZO animals. In summary, cerebrovascular reactivity to both endothelium-dependent and -independent stimuli is severely compromised by SAH in IR animals.

Impact of subarachnoid hemorrhage on local and global calcium signaling in cerebral artery myocytes

BACKGROUND

Ca2+ signaling mechanisms are crucial for proper regulation of vascular smooth muscle contractility and vessel diameter. In cerebral artery myocytes, a rise in global cytosolic Ca2+ concentration ([Ca2+]i) causes contraction while an increase in local Ca2+ release events from the sarcoplasmic reticulum (Ca2+ sparks) leads to increased activity of large-conductance Ca2+-activated (BK) K+ channels, hyperpolarization and relaxation. Here, we examined the impact of SAH on Ca2+ spark activity and [Ca2+]i in cerebral artery myocytes following SAH.

METHODS

A rabbit double injection SAH model was used in this study. Five days after the initial intracisternal injection of whole blood, small diameter cerebral arteries were dissected from the brain for study. For simultaneous measurement of arterial wall [Ca2+]i and diameter, vessels were cannulated and loaded with the ratiometric Ca2+ indicator fura-2. For measurement of Ca2+ sparks, individual myocytes were enzymatically isolated from cerebral arteries and loaded with the Ca2+ indicator fluo-4. Sparks were visualized using laser scanning confocal microscopy.

RESULTS

Arterial wall [Ca2+]i was significantly elevated and greater levels of myogenic tone developed in arteries isolated from SAH animals compared with arteries isolated from healthy animals. The L-type voltage-dependent Ca2+ channel (VDCC) blocker nifedipine attenuated increases in [Ca2+]i and tone in both groups suggesting increased VDCC activity following SAH. Membrane potential measurement using intracellular microelectrodes revealed significant depolarization of vascular smooth muscle following SAH. Further, myocytes from SAH animals exhibited significantly reduced Ca2+ spark frequency (~50%).

CONCLUSIONS

Our findings suggest decreased Ca2+ spark frequency leads to reduced BK channel activity in cerebral artery myocytes following SAH. This results in membrane potential depolarization, increased VDCC activity, elevated [Ca2+]i and decreased vessel diameter. We propose this mechanism of enhanced cerebral artery myocyte contractility may contribute to decreased cerebral blood flow and development of neurological deficits in SAH patients.

Nitric oxide in early brain injury after subarachnoid hemorrhage

Nitric Oxide (NO) is the major regulator of cerebral blood flow. In addition, it inhibits platelet adherence and aggregation, reduces adherence of leukocytes to the endothelium, and suppresses vessel injury. NO is produced on demand by nitric oxide synthase and has a very short half life. Hence maintenance of its cerebral level is crucial for normal vascular physiology. Time dependent alterations in cerebral NO level and the enzymes responsible for its synthesis are found after subarachnoid hemorrhage (SAH). Cerebral NO level decreases, recovers and increases within the first 24 h after SAH. Each change in cerebral NO level elicits a different pathological response form already compromised brain. These response range from constriction, platelet aggregation and vascular injury that occurs during the early hours and delayed occurring vasospasm, neuronal and axonal damage. This review summarizes the underlying mechanism and the consequence of alteration in cerebral NO level on brain during the first 72 h after SAH.