The prognostic value of systemic immune-inflammation index in patients with aneurysmal subarachnoid hemorrhage: a systematic review.

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating and life-threatening stroke subtype, that has a high disability and fatality rate. By the use of the systemic immune-inflammation index (SII), it is possible to understand the pathophysiology that underlies immune and inflammatory responses and anticipate consequences including delayed cerebral ischemia (DCI), delayed cerebral vasospasm, and functional outcome. A systematic search of the English-language literature in PubMed and Embase was performed to locate articles addressing the usage of SII in aSAH patients. The cutoff value, sensitivity, specificity, and area-under-the curve (AUC) of the receiver operating characteristic (ROC) curve were collected. Four publications were reviewed after applying the exclusion criteria from the 53 included articles. All the studies indicated that higher SII on admission was significantly associated with poor prognosis. The research examined in this paper provides the earliest indications that higher SII predicts DCI, delayed cerebral vasospasm, and functional outcome, even though other medical subspecialties have used this ratio for a long time to make such predictions.

Reversible cerebral Vasoconstriction syndrome intERnational CollaborativE (REVERCE) network: Study protocol and rationale of a multicentre research collaboration.

INTRODUCTION: Reversible cerebral vasoconstriction syndrome (RCVS) is a rare, but increasingly recognised cerebrovascular condition with an estimated annual age-standardised incidence of approximately three cases per million. Knowledge about risk factors and triggering conditions and information about prognosis and optimal treatment in these patients are limited. METHODS: The REversible cerebral Vasoconstriction syndrome intERnational CollaborativE (REVERCE) project aims to elucidate the epidemiological and clinical characteristics of RCVS by collecting individual patient data from four countries (France, Italy, Taiwan and South Korea) in the setting of a multicentric study. All patients with a diagnosis of definite RCVS will be included. Data on the distribution of risk factors and triggering conditions, imaging data, neurological complications, functional outcome, risk of recurrent vascular events and death and finally the use of specific treatments will be collected. Subgroup analyses will be made based on age, gender, aetiology, ethnicity and geographical region of residence. ETHICS AND DISSEMINATION: Ethical approval for the REVERCE study will be obtained from national or local institutional review boards in the participating centres. When needed, a standardised data transfer agreement will be provided for participating centres. We plan dissemination of our results in peer-reviewed international scientific journals and through conference presentations. We expect that the results of this unique study will lead to better understanding of clinical and epidemiological characteristics of RCVS patients.

Reversible cerebral vasoconstriction syndrome: A review of pathogenesis, clinical presentation, and treatment.

Reversible segmental narrowing of the intracranial arteries has been described since several decades in numerous clinical settings, using variable nosology. Twenty-one years ago, we tentatively proposed the unifying concept that these entities, based on similar clinical-imaging features, represented a single cerebrovascular syndrome. This "reversible cerebral vasoconstriction syndrome" or RCVS has now come of age. A new International Classification of Diseases code, (ICD-10, I67.841) has been established, enabling larger-scale studies. The RCVS2 scoring system provides high accuracy in confirming RCVS diagnosis and excluding mimics such as primary angiitis of the central nervous system. Several groups have characterized its clinical-imaging features. RCVS predominantly affects women. Recurrent worst-ever (thunderclap) headaches are typical at onset. While initial brain imaging is often normal, approximately one-third to half develop complications such as convexity subarachnoid hemorrhages, lobar hemorrhages, ischemic strokes located in arterial "watershed" territories and reversible edema, alone or in combination. Vasoconstriction evolves over hours to days, first affecting distal and then the more proximal arteries. An overlap between RCVS and primary thunderclap headache, posterior reversible encephalopathy syndrome, Takotsubo cardiomyopathy, transient global amnesia, and other conditions has been recognized. The pathophysiology remains largely unknown. Management is mostly symptomatic: headache relief with analgesics and oral calcium-channel blockers, removal of vasoconstrictive factors, and avoidance of glucocorticoids that can significantly worsen outcome. Intra-arterial vasodilator infusions provide variable success. Overall, 90-95% of admitted patients achieve complete or major resolution of symptoms and clinical deficits within days to weeks. Recurrence is exceptional, although 5% can later develop isolated thunderclap headaches with or without mild cerebral vasoconstriction.

Reversible Cerebral Vasoconstriction Syndrome Associated with Vasospasm of the Colic Arteries and Possibly Coronary Vasospasm.

BACKGROUND Reversible cerebral vasoconstriction syndrome (RCVS) is a disorder characterized by recurrent thunderclap headaches and reversible cerebral vasoconstriction. CASE REPORT Herein, we present the case of a man in his forties with a disease entity related to RCVS accompanied by vasospasm of the extracerebral blood vessels throughout the body. The patient presented to the Emergency Department with a severe headache and epigastric pain. Initially receiving a misdiagnosis of functional pain, he continued to experience severe recurrent headaches, most often after urinating or defecating and was referred to our department. Suspecting RCVS, we performed magnetic resonance angiography, which revealed beaded irregularity in the right anterior cerebral and V4 vertebral arteries. The patient also had epigastric pain that coincided with each headache. Electrocardiography revealed pronounced ST-segment elevation in leads I and aVL and inverted T wave in lead III, while abdominal computed tomography angiography showed narrowing of the colic arteries. We named this disease "reversible systemic vasoconstriction syndrome" (RSVS) as a potential suggested terminology for the future. CONCLUSIONS RSVS is a clinical syndrome characterized by thunderclap headaches and simultaneous unbearable pain in extracerebral organs. To the best of our knowledge, this is the first case report of RCVS with coronary and colic artery vasospasm. We need to take great care of patients with chest or abdominal pain accompanied by recurrent thunderclap headaches, since they can be misdiagnosed with functional or psychogenic disorders.

The link between reversible cerebral vasoconstriction syndrome and transient global amnesia.

Reversible cerebral vasoconstriction syndrome (RCVS) and transient global amnesia (TGA) are acute and self-limiting intra-cerebral conditions. Although previously studied as independent phenomena, there are increasing reports of co-occurrence of these two pathologies. We report a 55-year-old male who presented to the hospital with recurrent thunderclap headaches over the course of 1 week with sudden onset of anterograde memory loss. His medications included a selective serotonin reuptake inhibitor and intermittent use of pseudoephedrine. On examination he was amnestic to recent events and notably perseverating. Magnetic resonance imaging of the brain without contrast showed a small, punctate focus of restricted diffusion in the left hippocampus. He was diagnosed with TGA based on his clinical presentation. His headaches and amnesia resolved over the next 12 h throughout the course of his stay with acetaminophen and oral verapamil and he was discharged. Repeat computed tomography angiogram at 2 weeks revealed diffuse and segmental narrowing of the anterior and posterior intracranial circulation, which resolved on follow-up imaging at 3 months, confirming RCVS. The acute and reversible nature of these conditions and increasing reports of co-occurrence suggests a common pathophysiologic link. We review the literature highlighting similar cases and the presumed pathophysiology.

Cerebral Vasospasm: Practical Review of Diagnosis and Management.

BACKGROUND: Cerebral vasospasm is one of the frequent complications that can occur following subarachnoid hemorrhage (SAH). With new protocols in the management of SAH, the combined risk of death and long-term disability have been reduced by about 10% compared with the past. OBJECTIVE: This work aims to report the latest updates on the vasospasm developing after the SAH in patients in the ICU department. In this short review, we reviewed the latest scientific findings on the mechanisms of vasospasm, and in addition, we considered it necessary to review the literature to report the tools for early diagnosis of vasospasm and the best treatment strategies to prevent the negative outcome in patients admitted to ICU. AIM: The aim of this narrative review is to report the main characteristics of vasospasm, new diagnostic methods, and, especially, more effective treatment of vasospasm. MATERIALS AND METHODS: The peer-reviewed articles analyzed were selected from PubMed, Google scholar, Embase, and Scopus databases published in the previous 20 years using the keywords "vasospasm", "vasospasm diagnosis", "vasospasm and SAH", "vasospasm treatment", and nontraumatic brain injury. Among the 78 papers identified, 43 articles were selected; after the title - abstract examination and removing the duplicates, only 31 articles were examined. RESULTS: Vasospasm can be classified according to clinical (asymptomatic vs. symptomatic) and diagnostic (angiographic vs. ultrasound) methods. Various procedures such as TCD and CT perfusion are used for early diagnosis and close monitoring of this condition. The treatment of vasospasm consists of both prevention (nimodipine, statitis, and magnesium sulphate) and active treatment (mainly endovascular). CONCLUSION: As the review shows, vasospasm is a complication of SAH, a complication that is difficult to recognize early and treat with the best outcome. However, with the equipment we have, it has been possible to improve the outcome, even if it is still not ideal, in patients who develop vasospasm. Several studies are in the final stages to improve the outcome of this unfortunately frequent condition.

Vasoconstriction and long-term headache in reversible cerebral vasoconstriction syndrome.

BACKGROUND: Angiographic vasoconstriction in reversible cerebral vasoconstriction syndrome (RCVS) is often undetectable at symptom onset and the diagnosis relies on clinical presentation. Although thunderclap headache is a hallmark feature of RCVS, the incidence and predictors of long-term headaches (LTH) are incompletely understood. Our study aims were twofold: to examine the sensitivity and specificity of a recently developed score (RCVS2) for vasoconstriction detection in a real-world clinical context and describe the incidence and predictors of LTH beyond the acute phase of RCVS. METHODS: Retrospective analysis of consecutive patients with clinical diagnosis of RCVS in a tertiary hospital between 2017 and 2021. We examined associations between demographic factors, comorbidities, medications, imaging characteristics, and LTH (defined as at least one episode present at greater than 6-months follow-up necessitating medication). We separately examined the association between RCVS2 score and angiographic vasoconstriction and computed its sensitivity, specificity, and negative and positive predictive value based on established cutoffs (certain ≥ 5, negative ≤ 2). RESULTS: We included 55 patients, 50.5 (± 13.7) years; 41 (75%) female. 25 (49%) patients had LTH; only prior history of headache was significantly associated with LTH [OR 4.3, 95% CI (1.1-16.2), p = 0.03]. We found a significant association between RCVS2 score and angiographic vasoconstriction [OR 1.49, 95% CI (1.18-1.88), p = 0.001]; sensitivity, specificity, and positive and negative predictive value were 64%, 94%, 95% and 58% respectively. CONCLUSIONS: Approximately 50% of RCVS patients experienced LTH; only prior headache history was associated with its incidence. The RCVS2 score had a significant association with high specificity and positive predictive value for angiographic vasoconstriction in our cohort, validating its utility in improving the accuracy of diagnosis in the clinical setting.

Poor expression of miR-195-5p can assist the diagnosis of cerebral vasospasm after subarachnoid hemorrhage and predict adverse outcomes.

OBJECTIVE: Patients with spontaneous subarachnoid hemorrhage (SAH) may develop refractory arterial cerebral vasospasm (CVS), which is the leading cause of death in SAH patients. This study explored the clinical diagnostic value of serum miR-195-5p levels in CVS after SAH (SAH + CVS) and its relationship with the prognosis of SAH + CVS. METHODS: A total of 110 patients with spontaneous SAH were divided into the SAH group (N = 62) and SAH + CVS group (N = 58), with 60 healthy subjects as controls. The clinical data of blood glucose, blood sodium fluctuation, and serum lactic acid were recorded. miR-195-5p serum level was detected by RT-qPCR and its diagnostic value on SAH + CVS was analyzed by receiver operating characteristic curve. Serum levels of PDGF/IL-6/ET-1 and their correlation with miR-195-5p were analyzed using RT-qPCR, enzyme-linked immunosorbent assay, and Pearson's method. The patient prognosis was evaluated by Glasgow Outcome Scale. The effect of miR-195-5p levels on adverse prognosis was analyzed by Kaplan-Meier method and Cox regression analysis. RESULTS: miR-195-5p was lowly expressed in the serum of SAH patients and lower in SAH + CVS patients. Serum miR-195-5p level assisted the diagnosis of SAH and SAH + CVS and was negatively correlated with PDGF/IL-6/ET-1 levels and was an independent risk factor together with ET-1 and blood glucose for SAH + CVS. miR-195-5p low expression predicted a higher cumulative incidence of adverse outcomes and was an independent predictor of adverse outcomes. CONCLUSION: Poor expression of miR-195-5p can assist the diagnosis of SAH + CVS and predict higher adverse outcomes.

Transcranial Doppler ultrasound: Clinical applications from neurological to cardiological setting.

Transcranial Doppler (TCD) ultrasonography is a rapid, noninvasive, real-time, and low-cost imaging technique. It is performed with a low-frequency (2 MHz) probe in order to evaluate the cerebral blood flow (CBF) and its pathological alterations, through specific acoustic windows. In the recent years, TCD use has been expanded across many clinical settings. Actually, the most widespread indication for TCD exam is represented by the diagnosis of paradoxical embolism, due to patent foramen ovale, in young patients with cryptogenic stroke. In addition, TCD has also found useful applications in neurological care setting, including the following: cerebral vasospasm following acute subarachnoid hemorrhage, brain trauma, cerebrovascular atherosclerosis, and evaluation of CBF and cerebral autoregulation after an ischemic stroke event. The present review aimed to describe the most recent evidences of TCD utilization from neurological to cardiological setting.

Primary angiitis of the central nervous system and reversible cerebral vasoconstriction syndrome: analysis of the National Inpatient Sample.

INTRODUCTION: Primary angiitis of the central nervous system (PACNS) and reversible cerebral vasoconstriction syndrome (RCVS) are two rare syndromes that affect the cerebral vasculature. Both conditions have been shown to cause severe neurologic complications. Distinguishing these two conditions in clinical practice is often challenging. Here, we compare the clinical features and outcomes of RCVS and PACNS hospitalizations against the general adult inpatient population. MATERIALS AND METHODS: We conducted a retrospective review of hospitalizations with a diagnosis of PACNS or RCVS from 2016 to 2018 in the National Inpatient Sample (NIS) database. Multivariate analysis was performed to calculate adjusted odds ratios (ORadj) for hospital outcomes. RESULTS: In the NIS, 3305 hospitalizations had a diagnosis of RCVS and 6035 hospitalizations had a diagnosis of PACNS. RCVS hospitalizations had a significantly greater association with cerebral aneurysms (ORadj 23.80), hemiplegia/hemiparesis following subarachnoid hemorrhage (SAH) (ORadj 324.09), ischemic stroke (ORadj 7.59), and nontraumatic SAH (ORadj 253.61). PACNS hospitalizations had a significantly greater association with hemiplegia/hemiparesis following cerebrovascular accident (CVA) (ORadj 6.16), ischemic stroke (ORadj 11.55), nontraumatic SAH (ORadj 7.29), seizure (ORadj 2.49), and in-hospital mortality (ORadj 2.85). CONCLUSIONS: We performed an analysis of the NIS to better understand RCVS and PACNS hospitalizations. Severe neurologic events including CVA and SAH were elevated in both, but SAH and related hemiplegia/hemiparesis were extremely common among RCVS hospitalizations. In-hospital mortality was elevated in PACNS but not RCVS. This information can be used to help clinicians better understand, distinguish, and diagnose these conditions. Key Points • Despite clear description of RCVS and PACNS in the medical literature, there remains a scarcity of national population-based studies comparing these two entities against the general adult inpatient population. • This study aims to fill knowledge gaps in this area. • Here, we compare the clinical features and outcomes of RCVS and PACNS hospitalizations against the general adult inpatient population.

Clazosentan: First Approval.

Clazosentan (PIVLAZ™) is a small molecule, endothelin (ET) A receptor-selective antagonist being developed by Idorsia Pharmaceuticals. ETA receptor inhibition by clazosentan decreases ET-related cerebral vasospasm, which may occur after an aneurysmal subarachnoid haemorrhage. Clazosentan has been approved in Japan for use in the prevention of cerebral vasospasm, vasospasm-related cerebral infarction and cerebral ischaemic symptoms after aneurysmal subarachnoid haemorrhage, following the results from the JapicCTI163369 and JapicCTI163368 phase III trials. This article summarises the milestones in the development of clazosentan leading to this first approval in this indication.

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.

Chemical Angioplasty with Nitroglycerin for Vasospasm after Subarachnoid Hemorrhage: Case Series and Review

Introduction Vasospasm is a common and potentially devastating complication in patients with subarachnoid hemorrhage, causing high morbidity and mortality. There is no effective and consistent way to prevent or treat cerebral vasospasm capable of altering the morbidity and mortality of this complication. Animal and human studies have attempted to show improvement in aneurysmal vasospasm. Some sought their prevention; others, the treatment of already installed vasospasm. Some achieved only angiographic improvement without clinical correlation, others achieved both, but with ephemeral duration or at the expense of very harmful associated effects. Endovascular techniques allow immediate and aggressive treatment of cerebral vasospasm and include methods such as mechanical and chemical angioplasty. These methods have risks and benefits. Objectives To analyze the results of chemical angioplasty using nitroglycerin (GTN). In addition, to performa comprehensive review and analysis of aneurysmal vasospasm. Methods We describe our series of 77 patients treated for 8 years with angioplasty for vasospasm, either mechanical (with balloon), chemical (with GTN) or both. Results Eleven patients received only balloon; 37 received only GTN; 29 received both. Forty-four patients (70.1%) evolved with delayed cerebral ischemia and 19 died (mortality of 24.7%). Two deaths were causally related to the rupture of the vessel by the balloon. The only predictors of poor outcome were the need for external ventricular drainage in the first hours of admission, and isolated mechanical angioplasty. Conclusions Balloon angioplasty has excellent results, but it is restricted to proximal vessels and is not without complications. Chemical angioplasty using nitroglycerin has reasonable but short-lived results and further research is needed about it. It is restricted to vasospasm angioplasties only in hospitals, like ours, where better and more potent vasodilator agents are not available.

Large practice variations in diagnosis and treatment of delayed cerebral ischemia after subarachnoid hemorrhage.

BACKGROUND: Delayed cerebral ischemia (DCI) contributes to poor outcomes after subarachnoid hemorrhage (SAH). The pathophysiology of DCI is not fully understood, which has hindered the adoption of a uniform definition. Furthermore, a reliable diagnostic test and an effective evidence-based treatment are lacking. This could lead to variations in care. METHODS: A web-based survey on the variations in the definition, diagnosis, and treatment of DCI was designed and sent to 314 intensivists, neurologists, and neurosurgeons of all 9 hospitals in the Netherlands who care for patients with SAH. The responders were categorized into physicians responsible for the coordination of SAH care and those who were not. For questions on the definition and diagnosis, only the responses from the coordinating physicians were evaluated. For the treatment questions, all the responses were evaluated. RESULTS: The response rate was 34% (106 of 314). All 9 hospitals were represented. Of the responses, 27 did not provide answers for the definition, diagnosis, or treatment questions; 79 responses were used for analysis. Signs of vasospasm were required by 21 of the 47 coordinating physicians (44%) when considering DCI. Of the 47 coordinating physicians, 24 (51%) did not use a diagnostic test results for a positive diagnosis of DCI. When patients were discharged within 21 days, 33 of the 73 responders (45%) did not provide a prescription for nimodipine continuation. Finally, all but one hospital had treated DCI with hypertension induction. CONCLUSIONS: We found large variations in the definition, diagnosis, and treatment of DCI in the Netherlands. In the absence of evidence-based treatment, standardization of management seems warranted in an effort to optimize DCI care.

The management of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

Aneurysmal subarachnoid hemorrhage (SAH) is a rare event affecting relatively young patients therefore leading to a high social impact. The management of SAH follows a biphasic course with early brain injuries in the first 72 hours followed by a phase at risk of secondary deterioration due to delayed cerebral ischemia (DCI) in 20 to 30% patients. Cerebral infarction from DCI is the most preventable cause of mortality and morbidity after SAH. DCI prevention, early detection and treatment is therefore advocated. Formerly limited to the occurrence of vasospasm, DCI is now associated with multiple pathophysiological processes involving for instance the macrocirculation, the microcirculation, neurovascular units, and inflammation. Therefore, the therapeutic targets and management strategies are also evolving and are not only focused on proximal vasospasm. In this review, we describe the current knowledge of DCI pathophysiology. We then discuss the diagnosis strategies that may guide physicians at the bedside with a multimodal approach in the unconscious patient. We will present the prevention strategies that have proven efficient as well as future targets and present the therapeutic approach that is currently being developed when a DCI occurs.

Angiographic vasospasm and delayed cerebral ischemia after subarachnoid hemorrhage: Moving from theoretical to practical research pertinent to neurosurgical care.

BACKGROUND AND PURPOSE: Delayed cerebral ischemia (DCI) and angiographic vasospasm following subarachnoid hemorrhage (SAH) have been associated for more than 50years. We aimed to examine whether the knowledge gained by theoretical research on vasospasm has actually translated into better patient outcomes in practice. METHODS: This is a narrative review of the concept of vasospasm as a cause of DCI after SAH. We discuss recent studies that have assessed the accuracy and reliability of the diagnostic tests (transcranial Doppler ultrasound [TCD], CT angiography, and catheter angiography), which are used to identify SAH patients at-risk of DCI. RESULTS: Both the diagnostic accuracy of TCD and the reliability of CT angiography to identify patients in severe vasospasm are poor. For the gold standard catheter angiography, the repeatability of the diagnosis of vasospasm, made by multiple raters, is only fair. Interventions on angiographic vasospasm have never been proven to improve patient outcomes. A pragmatic trial integrating the meaning of the diagnosis of vasospasm into a study protocol that assesses the value of endovascular interventions in the prevention of DCI after SAH seems to be in order. Such a trial could provide a pragmatic definition of clinically meaningful vasospasm. CONCLUSION: We must move beyond research conceived as an enterprise aiming to acquire theoretical knowledge to one where research is integrated into clinical practice to improve clinical outcomes in real time.

Diagnostic Sensitivity of Plasma Endothelin-1 for Cerebral Vasospasm After Subarachnoid Hemorrhage, a Multicentre Double-Blind Study.

The purpose of this study is to establish the diagnostic sensitivity of Endothelin-1 for risk stratification and screening of clinical vasospasm after subarachnoid hemorrhage.This is a multicentre, observational study, correlating daily blood Endothelin-1 with clinical variables. Binary logistic regression used to examine if Endothelin-1 levels could be used to predict clinical vasospasm. Bivariate modelling used to explore associations between patient characteristics and vasospasm. A Receiver Operating Curve used to explore cut-off values for Endothelin-1. Sensitivity and specificity was used to validate the cut-point found in the pilot study. A total of 96 patients were enrolled over two years. Median Endothelin-1 was higher for patients who experienced clinical vasospasm except for day-5, where median endothelin for patients without vasospasm was higher (3.6 IQR = 5.3), compared to patients with vasospasm (3.3 IQR = 8.5) although differences were not significant. The Receiver Operating Curve analysis confirmed that day-5 Endothelin-1 was not a good indicator of vasospasm, with an area under the curve of 0.506 (95% CI: 0.350-0.663, p = 0.938). The levels of Endothelin-1 in blood do not discriminate patients who may develop symptomatic vasospasm. The high variability in Endothelin-1 levels, aligns with the pathophysiological variability of most biomarkers, decreasing their ability to predict a clinical event.

Reversible cerebral vasoconstriction syndrome: A narrative review for emergency clinicians.

INTRODUCTION: Reversible Cerebral Vasoconstriction Syndrome (RCVS) is a rare cause of severe headache that can mimic other causes of sudden, severe headache and result in frequent emergency department (ED) visits. OBJECTIVE: This narrative review provides an evidence-based update concerning the presentation, evaluation, and management of RCVS for the emergency clinician. DISCUSSION: RCVS can present as recurrent, severe headaches that may be maximal in onset, known as a thunderclap headache. Distinguishing from other causes of thunderclap headache such as aneurysmal subarachnoid hemorrhage, cerebral venous thrombosis, and posterior reversible encephalopathy syndrome is challenging. Risk factors for RCVS include use of vasoactive substances, exertion, coughing, showering, sexual activity, and cervical artery dissection. Diagnosis relies on clinical features and imaging. Cerebral catheter digital subtraction angiography (DSA) is considered the gold standard imaging modality; however, computed tomography angiography or magnetic resonance angiography are reliable non-invasive diagnostic modalities. Treatment focuses on avoiding or removing the offending agent, administration of calcium channel blockers such as nimodipine, and reversing anticoagulation if bleeding is present. Although most cases have a benign course and resolve within 3 months, focal subarachnoid hemorrhage, intracerebral hemorrhage, permanent neurologic disability, or death can occur in a minority of cases. CONCLUSIONS: Diagnosis and appropriate management of RCVS can be aided by understanding key aspects of the history and examination. The emergency clinician can then obtain indicated imaging, confirming the diagnosis and allowing for appropriate management.