Case-Fatality and Functional Outcome after Subarachnoid Hemorrhage (SAH) in INternational STRoke oUtComes sTudy (INSTRUCT)

Optimization and evaluation of an experimental subarachnoid hemorrhage model in mice

Subarachnoid hemorrhage (SAH) occurs when blood enters the subarachnoid space, typically due to aneurysm rupture, triggering complex pathophysiological processes. A reliable animal model is crucial for simulating SAH and investigating mechanisms of brain white matter injury. SAH was induced in C57BL/6J mice using an intraluminal perforation technique. Various filaments were tested to determine the optimal one, and filament depth was carefully measured. Postoperative evaluations included monitoring body weight, blood distribution on the skull, and clot formation. Cerebral blood flow was assessed, and neurological function was evaluated using modified Garcia scores, open field tests, and gait analysis. Myelin integrity was assessed by Luxol fast blue staining, and immunofluorescence was used to examine myelin, microglia, and neuronal integrity in the cortex and striatum. Using 4 - 0 polypropylene filaments advanced to 13 ± 1 mm at a 15-20 degree, we established a stable SAH mouse model with a success rate of 91.43% and a mortality rate of 6.25%. The SAH group showed motor impairments at 48 h post-surgery, along with myelin damage in the corpus callosum and striatum, oligodendrocyte damage, and neuronal injury.Our improved intraluminal perforation technique offers a stable and standardized SAH model, providing a reliable platform for studying SAH pathophysiology and testing new therapies.

Neutrophils extracellular traps myeloperoxidase and elastase predict cerebral vasospasms after aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a highly fatal and morbid disease. Despite successful coiling or clipping of a ruptured aneurysm, the patients suffer post-aSAH complications, including early brain injury, cerebral vasospasm (CVS), delayed cerebral ischemia (DCI), and systemic infections that mainly determine the clinical outcomes. Diagnostic biomarkers to predict accurately post-aSAH complications are needed. In this prospective exploratory study, we investigated the predictive value of neutrophil extracellular traps (NETs) components for CVS after aSAH. In the study, 62 patients with aSAH, 17 patients with unruptured cerebral aneurysms, and 12 healthy controls were included. The serum levels of myeloperoxidase (MPO), elastase (ELA), and citrullinated histone H3 (cH3) on day 1 and day 4 of hospital admission were measured with ELISA. Data were scaled using the Yeo-Johnson transformation. Values in two groups were compared using a t-test and in multiple groups using ANOVA. Logistic regression was used to model the outcome probability, including CVS, as the function of ELISA values. Among the patients with aneurysms, those who suffered aSAH had significantly higher levels of MPO (113.9 ± 294.4 vs. 422.3 ± 319.0 ng/ml, p < 0.05), ELA (84.8 ± 221.0 vs. 199.2 ± 218.9 ng/ml, p < 0.05), and cH3 (0.0 ± 0.0 vs. 2.8 ± 1.5, ng/ml, p < 0.05) on day one after aSAH, suggesting the involvement of NETs components in pathophysiology of aSAH and the events following aSAH. Individually, MPO and ELA levels taken on day 1 after SAH did not differ between patients with CVS and patients without CVS. However, when taken together into a logistic model, they allowed for predicting CVS with high sensitivity (91 %) and specificity (79 %). MPO and ELA, along with other clinical parameters, can be used as early predictors of CVS in aSAH patients and can serve as guidance during treatment decisions in the management of aSAH.

Subarachnoid haemorrhage and intracranial aneurysms in Greenland in the period 2018-2021: incidence, outcome and familial disposition

Subarachnoid haemorrhages (SAH) caused by rupture of intracranial aneurysms (IA) are a severe condition. Earlier studies found a higher incidence of SAH in Greenlandic patients compared to Danish patients, with familial aggregation also higher in Greenland. However, updated data is lacking. To investigate the contemporary incidence, outcome, and familial disposition of SAH/IA in Greenlandic patients in 2018-2021. Greenlandic patients diagnosed with ruptured or unruptured IA (UIA) during 2018-2021 were included. Data was obtained from patient files, x-ray department, and discharge registry. Incidence rates were estimated as cases/100,000/year. Direct age-standardised incidence rates were calculated using WHO 2000-2025 as standards. Of 30 SAH patients, 20 (66.7%) were females, 10 (33.3%) males. Of 36 UIA patients, 27 (75.0%) were females, 9 (25.0%) males. For SAH, crude incidence was 13.4/100,000/year, age-standardised incidence was 10.8/100,000/year. Familial history was observed in 30.0% of SAH patients. 5 patients (16.7%) died before treatment, 28-day case-fatality rate (CFR) for all patients was 23.3%. Overall and age-standardised incidence rates were similar to previous studies but higher among females and compared to neighbouring countries. A high occurrence of familial history was reported. SAH remains a serious condition in Greenland, as evidenced by five fatalities before treatment was administered.

Treatment of Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage Using the Compliant Manually Adjustable Mesh Comaneci

Background and purpose: Cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage (aSAH) may lead to morbidity and mortality. Endovascular mechanical angioplasty may be performed if symptomatic CV is refractory to noninvasive medical management. Compliant and noncompliant balloons and manually adjustable mesh may be used in this indication. We describe our initial experience with the Comaneci (Rapid Medical, Yokneam, Israel) in cerebral vasospasm treatment following aSAH. Methods: All patients included in the prospective observational SAVEBRAIN PWI (NCT05276934 on clinicaltrial.gov) study who underwent cerebral angioplasty using the Comaneci device for the treatment of medically refractory and symptomatic CV after aSAH were identified. Patient demographic information, procedural details, and outcomes were obtained from electronic medical records. Results: Between February 2022 and June 2023, seven consecutive patients underwent CV treatment with the Comaneci. Angioplasty of 37 arterial segments (supraclinoid internal carotid artery, A1, A2, and A3 segments of the anterior cerebral artery and M1 and M2 segments of the middle cerebral artery) was attempted, and 35/37 (95%) were performed. The vessel diameter improved significantly following angioplasty (+64%), while brain hypoperfusion decreased (-45% of the mean T Max). There was no long-term clinical complication, and 6% per-procedural complications occurred. Conclusions: The Comaneci is effective in the treatment of cerebral vasospasm following aSAH, bringing a new device in the armamentarium of the neurointerventionalist to perform intracranial angioplasty.

The urotensin II receptor triggers an early meningeal response and a delayed macrophage-dependent vasospasm after subarachnoid hemorrhage in male mice

Subarachnoid hemorrhage (SAH) can be associated with neurological deficits and has profound consequences for mortality and morbidity. Cerebral vasospasm (CVS) and delayed cerebral ischemia affect neurological outcomes in SAH patients, but their mechanisms are not fully understood, and effective treatments are limited. Here, we report that urotensin II receptor UT plays a pivotal role in both early events and delayed mechanisms following SAH in male mice. Few days post-SAH, UT expression is triggered by blood or hemoglobin in the leptomeningeal compartment. UT contributes to perimeningeal glia limitans astrocyte reactivity, microvascular alterations and neuroinflammation independent of CNS-associated macrophages (CAMs). Later, CAM-dependent vascular inflammation and subsequent CVS develop, leading to cognitive dysfunction. In an SAH model using humanized UTh+/h+ male mice, we show that post-SAH CVS and behavioral deficits, mediated by UT through Gq/PLC/Ca2+ signaling, are prevented by UT antagonists. These results highlight the potential of targeting UT pathways to reduce early meningeal response and delayed cerebral ischemia in SAH patients.

Outcome of Aneurysmal Subarachnoid Hemorrhage Not Altered With Transatlantic Airplane Transfer: A Bicentric Matched Case-control Study

OBJECTIVE

It is recommended that ruptured cerebral aneurysms are treated in a high-volume center within 72 hours of ictus. We assessed the impact of long-distance aeromedical evacuation in patients presenting aSAH.

METHODS

This case-control study compared patients with aneurysmal subarachnoid hemorrhage (aSAH) who had a 6750 km air transfer from Guadeloupe (a Caribbean island) to Paris, France, for neurointerventional management in a tertiary center with a matched cohort from Paris region treated in the same center over a 10-year period (2010 to 2019). The 2 populations were matched on age, sex, World Federation of Neurological Surgeons score, and Fisher score. The primary outcome was a 1-year modified Rankin Scale score ≤3. Secondary outcomes included time from diagnosis to securing aneurysm, 1-year mortality, and a cost analysis.

RESULTS

Among 128 consecutive aSAH transferred from Guadeloupe, 93 were matched with 93 patients from the Paris area. The proportion of patients with 1-year modified Rankin Scale ≤3 (75% vs 82%, respectively; P= 0.5) and 1-year mortality (18% vs 14%, respectively; P= 0.2) was similar in the Guadeloupe and Paris groups. The median (interquartile range: Q1, Q3) time from diagnosis to securing the aneurysm was higher in the patients from Guadeloupe than those from Paris (48 [30, 63] h vs 23 [12, 24] h, respectively; P< 0.001). Guadeloupean patients received mechanical ventilation (58% vs 38%; P< 0.001) and external ventricular drainage (55% vs 39%; P= 0.005) more often than those from Paris. The additional cost of treating a Guadeloupe patient in Paris was estimated at 7580 Euros or 17% of the estimated cost in Guadeloupe.

CONCLUSIONS

Long-distance aeromedical evacuation of patients with aSAH from Guadeloupe to Paris resulted in a 25-hour increase in time to aneurysm coiling embolization time but did not impact 1-year functional outcomes or mortality.

Decision-Making for Preventive Interventions in Asymptomatic Patients

The decision to treat an incidental finding in an asymptomatic patient results from careful risk-benefit consideration and is often challenging. One of the main aspects is after how many years the group who underwent the intervention and faced the immediate treatment complications will gain a treatment benefit over the conservatively managed group, which maintains a lower but ongoing risk. We identify a common error in decision-making. We illustrate how a risk-based approach using the classical break-even point at the Kaplan-Meier curves can be misleading and advocate for using an outcome-based approach, counting the cumulative number of lost quality-adjusted life years instead. In clinical practice, we often add together the yearly risk of the natural course up to the time point where the number equals the risk of the intervention and assume that the patient will benefit from an intervention beyond this point in time. It corresponds to the crossing of the Kaplan-Meier curves. However, because treatment-related poor outcome occurs at the time of the intervention, while the poor outcome in the conservative group occurs over a given time period, the true benefit of retaining more quality-adjusted life years in the interventional group emerges at a much later time. To avoid overtreatment of patients with asymptomatic diseases, decision-making should be outcome-based with counting the cumulative loss of quality-adjusted life years, rather than risk-based, comparing the interventional risk with the ongoing yearly risk of the natural course.

Diagnosis and endovascular management of vasospasm after aneurysmal subarachnoid hemorrhage - survey of real-life practices

BACKGROUND

Vasospasm and delayed cerebral ischemia (DCI) are the leading causes of morbidity and mortality after intracranial aneurysmal subarachnoid hemorrhage (aSAH). Vasospasm detection, prevention and management, especially endovascular management varies from center to center and lacks standardization. We aimed to evaluate this variability via an international survey of how neurointerventionalists approach vasospasm diagnosis and endovascular management.

METHODS

We designed an anonymous online survey with 100 questions to evaluate practice patterns between December 2021 and September 2022. We contacted endovascular neurosurgeons, neuroradiologists and neurologists via email and via two professional societies - the Society of NeuroInterventional Surgery (SNIS) and the European Society of Minimally Invasive Neurological Therapy (ESMINT). We recorded the physicians' responses to the survey questions.

RESULTS

A total of 201 physicians (25% [50/201] USA and 75% non-USA) completed the survey over 10 months, 42% had >7 years of experience, 92% were male, median age was 40 (IQR 35-46). Both high-volume and low-volume centers were represented. Daily transcranial Doppler was the most common screening method (75%) for vasospasm. In cases of symptomatic vasospasm despite optimal medical management, endovascular treatment was directly considered by 58% of physicians. The most common reason to initiate endovascular treatment was clinical deficits associated with proven vasospasm/DCI in 89%. The choice of endovascular treatment and its efficacy was highly variable. Nimodipine was the most common first-line intra-arterial therapy (40%). Mechanical angioplasty was considered the most effective endovascular treatment by 65% of neurointerventionalists.

CONCLUSION

Our study highlights the considerable heterogeneity among the neurointerventional community regarding vasospasm diagnosis and endovascular management. Randomized trials and guidelines are needed to improve standard of care, determine optimal management approaches and track outcomes.

The influence of epigenetic biological age on key complications and outcomes in aneurysmal subarachnoid haemorrhage

BACKGROUND

We aimed to investigate the association between DNA-methylation biological age (B-age) calculated as age acceleration (ageAcc) and key aneurysmal subarachnoid haemorrhage (aSAH) complications such as vasospasm, delayed cerebral ischaemia (DCI), poor outcome, and mortality.

METHODS

We conducted a prospective study involving 277 patients with aSAH. B-age was determined in whole blood samples using five epigenetic clocks: Hannum's, Horvath's, Levine's and both versions of Zhang's clocks. Age acceleration was calculated as the residual obtained from regressing out the effect of C-age on the mismatch between C-age and B-age. We then tested the association between ageAcc and vasospasm, DCI and 12-month poor outcome (mRS 3-5) and mortality using linear regression models adjusted for confounders.

RESULTS

Average C-age was 55.0 years, with 66.8% being female. Vasospasm occurred in 143 cases (51.6%), DCI in 70 (25.3%) and poor outcomes in 99 (35.7%), with a mortality rate of 20.6%. Lower ageAcc was linked to vasospasm in Horvath's and Levine's clocks, whereas increased ageAcc was associated with 12-month mortality in Hannum's clock. No significant differences in ageAcc were found for DCI or poor outcome at 12 months with other clocks.

CONCLUSIONS

Our study indicates that B-age is independently associated with vasospasm and 12-month mortality in patients with aSAH. These findings underscore the potential role of epigenetics in understanding the pathophysiology of aSAH-related complications and outcomes.

Treatment of Cerebral Vasospasm Following Aneurysmal Subarachnoid Hemorrhage using the Neurospeed Semi-compliant Balloon

BACKGROUND AND PURPOSE

Cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage (aSAH) may lead to morbidity and mortality. Endovascular mechanical angioplasty may be performed if symptomatic CV is refractory to noninvasive medical management. Off-label compliant remodelling balloons tend to conform to the course of the vessel, contrary to noncompliant or semi-compliant balloons. Our objective is to describe our initial experience with the semi-compliant Neurospeed balloon (approved for intracranial stenosis) in cerebral vasospasm treatment following aSAH.

METHODS

All patients included in the prospective observational SAVEBRAIN PWI (NCT05276934 on clinicaltrial.gov) study who underwent cerebral angioplasty using the Neurospeed balloon for the treatment of medically refractory and symptomatic CV after aSAH were identified. Patient demographic information, procedural details and outcomes were obtained from electronic medical records.

RESULTS

Between February 2022 and June 2023, 8 consecutive patients underwent CV treatment with the Neurospeed balloon. Angioplasty of 48 arterial segments (supraclinoid internal carotid artery, A1 and A2 segments of the anterior cerebral artery, M1 and M2 segments of the middle cerebral artery) was attempted and 44/48 (92%) were performed. The vessel diameter significantly improved following angioplasty (+81%), while brain hypoperfusion decreased (-81% of the mean TMax). There was no long-term clinical complication, 4% periprocedural complications occurred.

CONCLUSION

The semi-compliant Neurospeed balloon is effective in the treatment of cerebral vasospasm following aSAH, bringing a new device into the armamentarium of the neurointerventionalist to perform intracranial angioplasty.

Sex Differences in Case Fatality of Aneurysmal Subarachnoid Hemorrhage: A Systematic Review

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (SAH) is more common in women than in men, contrary to most cardiovascular diseases. However, it is unclear whether the case fatality rate (CFR) of SAH also differs by sex. Thus, we performed a systematic review to address the relationship between sex and SAH CFRs.

METHODS

We conducted a systematic literature search in PubMed, Scopus, and Cochrane library databases. We focused on population-based studies that included both nonhospitalized and hospitalized SAHs and had either reported 1-month (28-31 day) SAH CFRs separately for men and women or calculated risk estimates for SAH CFR by sex. For quality classification, we used the Cochrane Collaboration Handbook and Critical Appraisal Skills Program guidelines. We pooled the study cohorts and calculated relative risk ratios (RRs) with 95% confidence intervals (CIs) for SAH death between women and men using a random-effects meta-analysis model.

RESULTS

The literature search yielded 5,592 initial publications, of which 33 study cohorts were included in the final review. Of the 33 study cohorts, only three reported significant sex differences, although the findings were contradictory. In the pooled analysis of all 53,141 SAH cases (60.3% women) from 26 countries, the 1-month CFR did not differ (RR = 0.99 [95% CI: 0.93-1.05]) between women (35.5%) and men (35.0%). According to our risk-of-bias evaluation, all 33 study cohorts were categorized as low quality. The most important sources of bias risks were related to the absence of proper confounding control (all 33 study cohorts), insufficient sample size (27 of 33 study cohorts), and poor/unclear diagnostic accuracy (27 of 33 study cohorts).

CONCLUSION

Contrary to SAH incidence rates, the SAH CFRs do not seem to differ between men and women. However, since none of the studies were specifically designed to examine the sex differences in SAH CFRs, future studies on the topic are warranted.

The Role of NF-κB in Intracranial Aneurysm Pathogenesis: A Systematic Review

Intracranial aneurysms (IAs) are abnormal dilations of the cerebral vessels, which pose a persistent threat of cerebral hemorrhage. Inflammation is known to contribute to IA development. The nuclear factor "kappa-light-chain-enhancer" of activated B-cells (NF-κB) is the major driver of inflammation. It increases the expression of inflammatory markers and matrix metalloproteinases (MMPs), which contribute heavily to the pathogenesis of IAs. NF-κB activation has been linked to IA rupture and resulting subarachnoid hemorrhage. Moreover, NF-κB activation can result in endothelial dysfunction, smooth muscle cell phenotypic switching, and infiltration of inflammatory cells in the arterial wall, which subsequently leads to the initiation and progression of IAs and consequently results in rupture. After a systematic search, abstract screening, and full-text screening, 30 research articles were included in the review. In this systematic review, we summarized the scientific literature reporting findings on NF-κB's role in the pathogenesis of IAs. In conclusion, the activation of the NF-κB pathway was associated with IA formation, progression, and rupture.

Adverse events associated with microsurgial treatment for ruptured intracerebral aneurysms: a prospective nationwide study on subarachnoid haemorrhage in Sweden

BACKGROUND

Adverse events (AEs) or complications may arise secondary to the treatment of aneurysmal subarachnoid haemorrhage (SAH). The aim of this study was to identify AEs associated with microsurgical occlusion of ruptured aneurysms, as well as to analyse their risk factors and impact on functional outcome.

METHODS

Patients with aneurysmal SAH admitted to the neurosurgical centres in Sweden were prospectively registered during a 3.5-year period (2014-2018). AEs were categorised as intraoperative or postoperative. A range of variables from patient history and SAH characteristics were explored as potential risk factors for an AE. Functional outcome was assessed approximately 1 year after the bleeding using the extended Glasgow Outcome Scale.

RESULTS

In total, 1037 patients were treated for ruptured aneurysms, of which, 322 patients were treated with microsurgery. There were 105 surgical AEs in 97 patients (30%); 94 were intraoperative AEs in 79 patients (25%). Aneurysm rerupture occurred in 43 patients (13%), temporary occlusion of the parent artery >5 min in 26 patients (8%) and adjacent vessel injury in 25 patients (8%). High Fisher grade and brain oedema on CT were related to increased risk of AEs. At follow-up, 38% of patients had unfavourable outcome. Patients suffering AEs were more likely to have unfavourable outcome (OR 2.3, 95% CI 1.10 to 4.69).

CONCLUSION

Intraoperative AEs occurred in 25% of patients treated with microsurgery for ruptured intracerebral aneurysm in this nationwide survey. Although most operated patients had favourable outcome, AEs were associated with increased risk of unfavourable outcome.

Aneurysmal subarachnoid haemorrhage in Indigenous and non-Indigenous Australians: A retrospective study assessing patient characteristics and outcome

INTRODUCTION

Smoking and hypertension are prevalent among Indigenous Australians (Aboriginal and Torres Strait Islanders). We investigated if these risk factors suggest a greater rate of aneurysmal subarachnoid haemorrhage in Indigenous Australians (IA) compared to non-IA.

MATERIALS AND METHODS

A retrospective cross-sectional study was performed on data retrieved from the Nationwide Hospital Morbidity Database for all aSAH cases in Australia between 2012 and 2018. Patient characteristics, radiological findings, aneurysm characteristics, treatment characteristics and discharge outcomes were assessed. Crude and age-adjusted incidences, trends of aSAH and case fatality rate over time were calculated.

RESULTS

A total of 12,286 patients were included (285 IA, 12,001 non-IA). Indigenous aSAH patients were significantly younger than non-IA, with 89.8 percent of IA younger than 65 years old (p < 0.001). Crude annual incidences were similar between the 2 cohorts, however age-adjusted incidence shows a RR = 1.4 at 45-59 years in IA patients, compared with their non-IA counterparts. 30-day mortality was similar between the two groups, at 25.3 and 26.9% for IA and non-IA groups, respectively.

CONCLUSION

This 10 year nationwide retrospective study highlights a disparity between the crude and age-adjusted incidence of aSAH in IA compared to non-IA.