Hemorrhagic Stroke Academia Industry (HEADS) Roundtable Participants. Unmet Needs and Challenges in Clinical Research of Intracerebral Hemorrhage

Astrocytic mitochondria modulate poststroke splenic immune responses, promote interleukin 10 production, and mediate neuroprotection after intracerebral hemorrhage

We recently demonstrated that systemically transplanted astrocytic mitochondria enter the intracerebral hemorrhage (ICH)-affected brain, where they protect the neurons by mitigating oxidative damage via upregulation of the manganese superoxide dismutase (Mn-SOD), ultimately contributing to functional recovery after ICH in mice. Although our previous study clearly demonstrated the beneficial effects of mitochondria within the brain, the effect of transferred mitochondria on the peripheral system was not yet studied. Thus, here, we studied the impact of astrocytic mitochondria transfer on post-ICH recovery and modulation of systemic immune responses. We used the autologous blood injection model for the mouse ICH surgery. Mice subjected to ICH received astrocytic mitochondria intravenously at 1 h, 7, and 14 days post-ICH onset, and the splenic immune responses of these mice were analyzed at 21 days. An ICH-like injury was induced in vitro using primary cultured neurons treated with recombinant interleukin-10, and cell viability, reactive oxygen species levels, and gene expressions were analyzed. We demonstrate that systemic transplantation of astrocytic mitochondria increases the population of splenic B cells, production of interleukin-10 by B cells, and plasma interleukin-10 levels in mice after ICH. Furthermore, in the ICH-like injury in vitro, exogenous interleukin-10 (to model spleen-mediated interleukin-10 increase) upregulated Mn-SOD expression in the cultured neurons and promoted neuronal survival and neuroplasticity-related gene expressions, suggesting interleukin-10 role in cytoprotection and repair/recovery under ICH-like condition. Thus, systemic transfer of astrocytic mitochondria modulates post-ICH peripheral immune responses, which may participate in functional recovery.

miR-874-3p Alleviates Macrophage-Mediated Inflammatory Injury in Intracerebral Hemorrhage by Targeting HIPK2

Macrophages mediate secondary inflammatory injury after intracerebral hemorrhage (ICH). This study aimed to investigate the role and molecular mechanisms of miR-874-3p in macrophage polarization. A mice model of ICH was constructed by autologous blood injection. Macrophages were treated with erythrocyte lysates to construct an ICH cell model. Real-time quantitative reverse transcription PCR (RT-qPCR) was used to detect miR-874-3p levels. Enzyme-Linked Immunosorbent Assay (ELISA) was used to detect macrophage polarization markers. Brain tissue water content and neurological deficit scores were used to assess the degree of inflammatory injury in ICH mice. RNA immunoprecipitation (RIP) and Dual-luciferase reporter (DLR) assays were used to analyze the targeting relationship between miR-874-3p and target mRNA. miR-874-3p levels were decreased in ICH mice and erythrocyte lysates-treated macrophages. miR-874-3p mimic alleviated inflammatory injury, decreased the levels of M1 macrophage markers, and increased the levels of M2 macrophage markers, suggesting that miR-874-3p is involved in ICH by regulating macrophage polarization. HIPK2 is the target mRNA of miR-874-3p and has the opposite expression pattern of miR-874-3p. Overexpression of HIPK2 attenuates the effect of elevated miR-874-3p levels on macrophage polarization and inflammatory brain injury in ICH mice. miR-874-3p regulates macrophage polarization in ICH by targeting HIPK2. Therefore, the miR-874-3p/HIPK2 axis may be a promising target for ICH treatment.

Microglial Mechanisms and Therapeutic Potential in Brain Injury Post-Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a particularly common public health problem with a high mortality and disability rate and no effective treatments to enhance clinical prognosis. The increased aging population, improved vascular prevention, and augmented use of antithrombotic agents have collectively contributed to the rise in ICH incidence over the past few decades. The exploration and understanding of mechanisms and intervention strategies has great practical significance for expanding treatments and improving prognosis of ICH. Microglia, as resident macrophages of central nervous system, are responsible for the first immune defense post-ICH. After ICH, M1 microglia is firstly activated by primary injury and thrombin; subsequently, reactive microglia can further amplify the immune response and exert secondary injury (eg, oxidative stress, neuronal damage, and brain edema). The pro-inflammatory phenotype transmits to M2 microglia within 7 days post-ICH, which plays a key role in erythrophagocytosis and limiting the inflammatory secondary injury. Microglial M2 polarization has significant implications for improving prognosis, this process can be mediated through crosstalk with other cells, metabolic changes, and microbiota interaction. Clarifying the effect, timing, and potential downstream effects of multiple mechanisms that synergistically trigger anti-inflammatory responses may be necessary for clinical translation. Analyses of such intricate interaction between microglia cells and brain injury/repair mechanisms will contribute to our understanding of the critical microglial responses to microenvironment and facilitating the discovery of appropriate intervention strategies. Here, we present a comprehensive overview of the latest evidences on microglial dynamics following ICH, their role in driving primary/secondary injury mechanisms as well as neurorepair/plasticity, and possible treatment strategies targeting microglia.

Blood Pressure Management in Early Aneurysmal Subarachnoid Hemorrhage: A National Cross-Sectional Survey of Canadian Intensivists and Cerebrovascular Neurosurgeons

BACKGROUND

In aneurysmal subarachnoid hemorrhage (aSAH), rebleeding of the culprit aneurysm is associated with significant morbidity and mortality. Blood pressure reduction to specific target levels, with the goal of preventing rebleeding, has been a mainstay of care prior to definitively securing the aneurysm. Clinical practice guidelines have recently changed and no longer recommend specific blood pressure targets. This survey aims to identify the reported practice patterns and beliefs regarding blood pressure management during the early phase of aSAH.

METHODS

We conducted a self-administered, Web-based survey of critical care physicians and cerebrovascular neurosurgeons practicing in Canada. The questionnaire contained 21 items, including 3 case-based scenarios to elicit blood pressure target selection, both before and after aneurysm securing.

RESULTS

In the presecured period, systolic blood pressures of 160 mm Hg (50% [144 of 287]) and 140 mm Hg (42% [120 of 287]) were the most frequently selected upper-limit targets. In the postsecured period, a systolic blood pressure of 180 mm Hg (32% [93 of 287]) was the most frequently selected upper-limit target, but there was a wide distribution of targets selected across all three cases ranging from 100 to > 200 mm Hg. A mean arterial pressure of 65 mm Hg was the most common lower-limit target in both the presecured and postsecured periods. There was little change in blood pressure targets with increasing clinical severity. Predictors of higher or lower blood pressure target selection and barriers to implementation of the desired target were identified.

CONCLUSIONS

During the presecured period, nearly half of the reported upper-limit blood pressure targets are lower than previous guideline recommendations. These targets remain consistent despite increasing clinical severity and could potentially exacerbate cerebral ischemia and negatively impact clinical outcomes. In the postsecured period, there is wide variation in the reported blood pressure targets. A clinical trial is urgently needed to guide decision-making.

How much of the variance in functional outcome related to intracerebral hemorrhage volume is already apparent in neurological status at admission?

BACKGROUND

Hematoma volume is a major pathophysiological hallmark of acute intracerebral hemorrhage (ICH). We investigated how the variance in functional outcome induced by the ICH volume is explained by neurological deficits at admission using a mediation model.

METHODS

Patients with acute ICH treated in three tertiary stroke centers between January 2010 and April 2019 were retrospectively analyzed. Mediation analysis was performed to investigate the effect of ICH volume (0.8 ml (5% quantile) versus 130.6 ml (95% quantile)) on the risk of unfavorable functional outcome at discharge defined as modified Rankin Score (mRS) ≥ 3 with mediation through National Institutes of Health Stroke Scale (NIHSS) at admission. Multivariable regression was conducted to identify factors related to neurological improvement and deterioration.

RESULTS

Three hundred thirty-eight patients were analyzed. One hundred twenty-one patients (36%) achieved mRS ≤ 3 at discharge. Mediation analysis showed that NIHSS on admission explained 30% [13%; 58%] of the ICH volume-induced variance in functional outcome at smaller ICH volume levels, and 14% [4%; 46%] at larger ICH volume levels. Higher ICH volume at admission and brainstem or intraventricular location of ICH were associated with neurological deterioration, while younger age, normotension, lower ICH volumes, and lobar location of ICH were predictors for neurological improvement.

CONCLUSION

NIHSS at admission reflects 14% of the functional outcome at discharge for larger hematoma volumes and 30% for smaller hematoma volumes. These results underscore the importance of effects not reflected in NIHSS admission for the outcome of ICH patients such as secondary brain injury and early rehabilitation.

Critical path activities in clinical trial setup and conduct: How to avoid bottlenecks and accelerate clinical trials

Most clinical trials are delayed due to scientific and/or operational challenges. Any effort to minimize delays can generate value for patients and sponsors. This article reviews critical path process steps commonly identified by practitioners, such as during protocol development, site contracting, or patient recruitment. Commonly considered measures, such as adding more trial sites or countries, were contrasted with less frequented measures, such as evidence-based feasibility or real-world evidence analysis, to help validate assumptions before clinical trial initiation. In a broad analysis, we integrated a literature review with a practitioner survey into a framework to help decision makers on the most critical process steps when setting up or conducting clinical trials in order to bring critical treatments to patients faster.

Association of Chronic Kidney Disease With Risk of Intracerebral Hemorrhage

Importance

The evidence linking chronic kidney disease (CKD) to spontaneous intracerebral hemorrhage (ICH) is inconclusive owing to possible confounding by comorbidities that frequently coexist in patients with these 2 diseases.

Objective

To determine whether there is an association between CKD and ICH risk.

Design, Setting, and Participants

A 3-stage study that combined observational and genetic analyses was conducted. First, the association between CKD and ICH risk was tested in the Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study, a multicenter case-control study in the US. All participants with available data on CKD from ERICH were included. Second, this analysis was replicated in the UK Biobank (UKB), an ongoing population study in the UK. All participants in the UKB were included in this study. Third, mendelian randomization analyses were implemented in the UKB using 27 CKD-related genetic variants to test for genetic associations. ERICH was conducted from August 1, 2010, to August 1, 2017, and observed participants for 1 year. The UKB enrolled participants between 2006 and 2010 and will continue to observe them for 30 years. Data analysis was performed from November 11, 2019, to May 10, 2022.

Exposures

CKD stages 1 to 5.

Main Outcomes and Measures

The outcome of interest was ICH, ascertained in ERICH via expert review of neuroimages and in the UKB via a combination of self-reported data and International Statistical Classification of Diseases, Tenth Revision, codes.

Results

In the ERICH study, a total of 2914 participants with ICH and 2954 controls who had available data on CKD were evaluated (mean [SD] age, 61.6 [14.0] years; 2433 female participants [41.5%]; 3435 male participants [58.5%]); CKD was found to be independently associated with higher risk of ICH (odds ratio [OR], 1.95; 95% CI, 1.35-2.89; P < .001). This association was not modified by race and ethnicity. Replication in the UKB with 1341 participants with ICH and 501 195 controls (mean [SD] age, 56.5 [8.1] years; 273 402 female participants [54.4%]; 229 134 male participants [45.6%]) confirmed this association (OR, 1.28; 95% CI, 1.01-1.62; P = .04). Mendelian randomization analyses indicated that genetically determined CKD was associated with ICH risk (OR, 1.56; 95% CI, 1.13-2.16; P = .007).

Conclusions and Relevance

In this 3-stage study that combined observational and genetic analyses among study participants enrolled in 2 large observational studies with different characteristics and study designs, CKD was consistently associated with higher risk of ICH. Mendelian randomization analyses suggest that this association was causal. Further studies are needed to identify the specific biological pathways that mediate this association.

Quantification of hematoma and perihematomal edema volumes in intracerebral hemorrhage study: Design considerations in an artificial intelligence validation (QUANTUM) study

BACKGROUND

Hematoma and perihematomal edema volumes are important radiographic markers in spontaneous intracerebral hemorrhage. Accurate, reliable, and efficient quantification of these volumes will be paramount to their utility as measures of treatment effect in future clinical studies. Both manual and semi-automated quantification methods of hematoma and perihematomal edema volumetry are time-consuming and susceptible to inter-rater variability. Efforts are now underway to develop a fully automated algorithm that can replace them. A (QUANTUM) study to establish inter-quantification method measurement equivalency, which deviates from the traditional use of measures of agreement and a comparison hypothesis testing paradigm to indirectly infer quantification method measurement equivalence, is described in this article. The Quantification of Hematoma and Perihematomal Edema Volumes in Intracerebral Hemorrhage study aims to determine whether a fully automated quantification method and a semi-automated quantification method for quantification of hematoma and perihematomal edema volumes are equivalent to the hematoma and perihematomal edema volumes of the manual quantification method.

METHODS/DESIGN

Hematoma and perihematomal edema volumes of supratentorial intracerebral hemorrhage on 252 computed tomography scans will be prospectively quantified in random order by six raters using the fully automated, semi-automated, and manual quantification methods. Primary outcome measures for hematoma and perihematomal edema volumes will be quantified via computed tomography scan on admission (<24 h from symptom onset) and on day 3 (72 ± 12 h from symptom onset), respectively. Equivalence hypothesis testing will be conducted to determine if the hematoma and perihematomal edema volume measurements of the fully automated and semi-automated quantification methods are within 7.5% of the hematoma and perihematomal edema volume measurements of the manual quantification reference method.

DISCUSSION

By allowing direct equivalence hypothesis testing, the Quantification of Hematoma and Perihematomal Edema Volumes in Intracerebral Hemorrhage study offers advantages over radiology validation studies which utilize measures of agreement to indirectly infer measurement equivalence and studies which mistakenly try to infer measurement equivalence based on the failure of a comparison two-sided null hypothesis test to reach the significance level for rejection. The equivalence hypothesis testing paradigm applied to artificial intelligence application validation is relatively uncharted and warrants further investigation. The challenges encountered in the design of this study may influence future studies seeking to translate artificial intelligence medical technology into clinical practice.

Development and Validation of a Clinical-Based Signature to Predict the 90-Day Functional Outcome for Spontaneous Intracerebral Hemorrhage

We aimed to develop and validate an objective and easy-to-use model for identifying patients with spontaneous intracerebral hemorrhage (ICH) who have a poor 90-day prognosis. This three-center retrospective study included a large cohort of 1,122 patients with ICH who presented within 6 h of symptom onset [training cohort, n = 835; internal validation cohort, n = 201; external validation cohort (center 2 and 3), n = 86]. We collected the patients’ baseline clinical, radiological, and laboratory data as well as the 90-day functional outcomes. Independent risk factors for prognosis were identified through univariate analysis and multivariate logistic regression analysis. A nomogram was developed to visualize the model results while a calibration curve was used to verify whether the predictive performance was satisfactorily consistent with the ideal curve. Finally, we used decision curves to assess the clinical utility of the model. At 90 days, 714 (63.6%) patients had a poor prognosis. Factors associated with prognosis included age, midline shift, intraventricular hemorrhage (IVH), subarachnoid hemorrhage (SAH), hypodensities, ICH volume, perihematomal edema (PHE) volume, temperature, systolic blood pressure, Glasgow Coma Scale (GCS) score, white blood cell (WBC), neutrophil, and neutrophil-lymphocyte ratio (NLR) (p < 0.05). Moreover, age, ICH volume, and GCS were identified as independent risk factors for prognosis. For identifying patients with poor prognosis, the model showed an area under the receiver operating characteristic curve of 0.874, 0.822, and 0.868 in the training cohort, internal validation, and external validation cohorts, respectively. The calibration curve revealed that the nomogram showed satisfactory calibration in the training and validation cohorts. Decision curve analysis showed the clinical utility of the nomogram. Taken together, the nomogram developed in this study could facilitate the individualized outcome prediction in patients with ICH.

The Power of Public-Private Partnership in Medical Technology Innovation: Lessons From the Development of Fda-Cleared Medical Devices for Assessment of Concussion

Given the convergence of the long and challenging development path for medical devices with the need for diagnostic capabilities for mild traumatic brain injury (mTBI/concussion), the effective role of public–private partnership (PPP) can be demonstrated to yield Food and Drug Administration (FDA) clearances and innovative product introductions. An overview of the mTBI problem and landscape was performed. A detailed situation analysis of an example of a PPP yielding an innovative product was further demonstrated. The example of PPP has led to multiple FDA clearances and product introductions in the TBI diagnostic product category where there was an urgent military and public need. Important lessons included defining the primary public and military health objective for new product introduction, the importance of the government–academia–industry PPP triad with a “collaboration towards solutions” Quality-by-Design (QbD) mindset to assure clinical validity with regulatory compliance, the development of device comparators and integration of measurements into a robust, evidence-based statistical and FDA pathway, and the utility of top-down, flexible, practical action while operating within governmental guidelines and patient safety.

CM-352 EFFICACY IN A MOUSE MODEL OF ANTICOAGULANT-ASSOCIATED INTRACRANIAL HAEMORRHAGE

BACKGROUND

Intracranial haemorrhage (ICH) is one of the major devastating complications of anticoagulation. Matrix metalloproteinases (MMPs) inhibition has been proposed as a novel pharmacological approach for ICH treatment.

OBJECTIVES

We evaluated the effects of CM-352 (MMPs-fibrinolysis inhibitor) in an experimental ICH model associated with oral anticoagulants as compared with clinically used prothrombin concentrate complex (PCC).

METHODS

ICH was induced by collagenase injection into the striatum of WT (C57BL/6J) anticoagulated mice (warfarin or rivaroxaban) and Mmp10 -/- mice. Hematoma volume and neurological deficits were measured 24h later by diaminobenzidine staining and different behavioural test. Circulating plasminogen activator inhibitor-1 (PAI-1) activity and interleukin-6 (IL-6) were measured in plasma samples and local inflammation was assessed by neutrophil infiltration. Finally, fibrinolytic effects of MMP-10 and rivaroxaban were evaluated by thromboelastometry and thrombin-activatable fibrinolysis inhibitor (TAFI) activation assays.

RESULTS

Only PCC reduced haemorrhage volume and improved functional outcome in warfarin-ICH, but both, PCC and CM-352 treatments, diminished haemorrhage volume (46%, p<0.01 and 64%, p<0.001, respectively) and ameliorated functional outcome in rivaroxaban-ICH. We further demonstrated that CM-352, but not PCC decreased neutrophil infiltration in the haemorrhage area at 24h. The effect of CM-352 could be related to MMP-10 inhibition since Mmp10-/- mice showed lower haemorrhage volume, better neurological score, reduced IL-6 levels and neutrophil infiltration, and increased PAI-1 after experimental ICH. Finally, we found that CM-352 reduced MMP-10 and rivaroxaban-related fibrinolytic effects in thromboelastometry and TAFI activation.

CONCLUSIONS

CM-352 treatment, by diminishing MMPs and rivaroxaban-associated fibrinolytic effects, might be a novel antihaemorrhagic strategy for rivaroxaban-associated ICH.

Association Between Perihematomal Perfusion and Intracerebral Hemorrhage Outcome

BACKGROUND

The prognostic impact of perihematomal hypoperfusion in patients with acute intracerebral hemorrhage (ICH) remains unclear. We tested the hypothesis that perihematomal hypoperfusion predicts poor ICH outcome and explored whether hematoma growth (HG) is the pathophysiological mechanism behind this association.

METHODS

A prospectively collected single-center cohort of consecutive ICH patients undergoing computed tomography perfusion on admission was analyzed. Cerebral blood flow (pCBF) was measured in the manually outlined perihematomal low-density area. pCBF was categorized into normal (40-55 mL/100 g/min), low (< 40 mL/100 g/min), and high (> 55 mL/100 g/min). HG was calculated as total volume increase from baseline to follow-up CT. A modified Rankin scale > 2 at three months was the outcome of interest. The association between cerebral perfusion and outcome was investigated with logistic regression, and potential mediators of this relationship were explored with mediation analysis.

RESULTS

A total of 155 subjects were included, of whom 55 (35.5%) had poor outcome. The rates of normal pCBF, low pCBF, and high pCBF were 17.4%, 68.4%, and 14.2%, respectively. After adjustment for confounders and keeping subjects with normal pCBF as reference, the risk of poor outcome was increased in patients with pCBF < 40 mL/100 g/min (odds ratio 6.11, 95% confidence interval 1.09-34.35, p = 0.040). HG was inversely correlated with pCBF (R = -0.292, p < 0.001) and mediated part of the association between pCBF and outcome (proportion mediated: 82%, p = 0.014).

CONCLUSION

Reduced pCBF is associated with poor ICH outcome in patients with mild-moderate severity. HG appears a plausible biological mediator but does not fully account for this association, and other mechanisms might be involved.

Targeting focal ischemic and hemorrhagic stroke neuroprotection: Current prospects for local hypothermia

Therapeutic hypothermia (TH) has applications dating back millennia. In modern history, however, TH saw its importation into medical practice where investigations have demonstrated that TH is efficacious in ischemic insults, notably cardiac arrest and hypoxic-ischemic encephalopathy. As well, studies have been undertaken to investigate whether TH can provide benefit in focal stroke (i.e., focal ischemia and intracerebral hemorrhage). However, clinical studies have encountered various challenges with induction and maintenance of post-stroke TH. Most clinical studies have attempted to use body-wide cooling protocols, commonly hindered by side effects that can worsen post-stroke outcomes. Some of the complications and difficulties with systemic TH can be circumvented by using local hypothermia (LH) methods. Additional advantages include the potential for lower target temperatures to be achieved and faster TH induction rates with LH. This systematic review summarizes the body of clinical and preclinical LH focal stroke studies and raises key points to consider for future LH research. We conclude with an overview of LH neuroprotective mechanisms and a comparison of LH mechanisms with those observed with systemic TH. Overall, whereas many LH studies have been conducted preclinically in the context of focal ischemia, insufficient work has been done in intracerebral hemorrhage. Furthermore, key translational studies have yet to be done in either stroke subtype (e.g., varied models and time-to-treat, studies considering aged animals or animals with co-morbidities). Few clinical LH investigations have been performed and the optimal LH parameters to achieve neuroprotection are unknown.

Recommended Primary Outcomes for Clinical Trials Evaluating Hemostatic Agents in Patients With Intracranial Hemorrhage: A Consensus Statement

IMPORTANCE

In patients with acute spontaneous or traumatic intracranial hemorrhage, early hemostasis is thought to be critical to minimize ongoing bleeding. However, research evaluating hemostatic therapies has been hampered by a lack of standardized clinical trial outcome measures.

OBJECTIVE

To identify appropriate primary outcomes for phase 2 and 3 clinical trials of therapies aimed at reducing acute intracranial bleeding.

EVIDENCE REVIEW

A comprehensive review of all previous clinical trials of hemostatic therapy for intracranial bleeding was performed, and studies measuring the frequency, risk factors, and association of intracranial bleeding with outcome of hemorrhage growth were included.

FINDINGS

A hierarchy of 3 outcome measures is recommended, with the first choice being a global patient-centered clinical outcome scale measured 30 to 180 days after the event; the second, a combined clinical and radiographic end point associating hemorrhage expansion with a poor patient-centered outcome at 24 hours or later; and the third, a radiographic measure of hemorrhage expansion at 24 hours alone. Additional recommendations stress the importance of separating various subtypes of bleeding when possible, early treatment within a standardized treatment window, and the routine use of computerized planimetry comparing continuous measures of absolute and relative hemorrhage growth as either a primary or secondary end point.

CONCLUSIONS AND RELEVANCE

Standardization of outcome measures in studies of intracranial bleeding and hemostatic therapy will support comparative effectiveness research and meta-analysis, with the goal of accelerating the translation of research into clinical practice. The 3 outcome measures proposed in this consensus statement could help this process.

Glibenclamide does not improve outcome following severe collagenase-induced intracerebral hemorrhage in rats

Intracerebral hemorrhage (ICH) is a devastating insult with few effective treatments. Edema and raised intracranial pressure contribute to poor outcome after ICH. Glibenclamide blocks the sulfonylurea 1 transient receptor potential melastatin 4 (Sur1-Trpm4) channel implicated in edema formation. While glibenclamide has been found to improve outcome and reduce mortality in animal models of severe ischemic stroke, in ICH the effects are less clear. In our previous study, we found no benefit after a moderate-sized bleed, while others have reported benefit. Here we tested the hypothesis that glibenclamide may only be effective in severe ICH, where edema is an important contributor to outcome. Glibenclamide (10 μg/kg loading dose, 200 ng/h continuous infusion) was administered 2 hours post-ICH induced by collagenase injection into the striatum of adult rats. A survival period of 24 hours was maintained for experiments 1-3, and 72 hours for experiment 4. Glibenclamide did not affect hematoma volume (~81 μL) or other safety endpoints (e.g., glucose levels), suggesting the drug is safe. However, glibenclamide did not lessen striatal edema (~83% brain water content), ionic dyshomeostasis (Na+, K+), or functional impairment (e.g., neurological deficits (median = 10 out of 14), etc.) at 24 hours. It also did not affect edema at 72 h (~86% brain water content), or overall mortality rates (25% and 29.4% overall in vehicle vs. glibenclamide-treated severe strokes). Furthermore, glibenclamide appears to worsen cytotoxic edema in the peri-hematoma region (cell bodies were 46% larger at 24 h, p = 0.0017), but no effect on cell volume or density was noted elsewhere. Overall, these findings refute our hypothesis, as glibenclamide produced no favorable effects following severe ICH.

The Story of Intracerebral Hemorrhage: From Recalcitrant to Treatable Disease

This invited special report is based on an award presentation at the World Stroke Organization/European Stroke Organization Conference in November of 2020 outlining progress in the acute management of intracerebral hemorrhage (ICH) over the past 35 years. ICH is the second most common and the deadliest type of stroke for which there is no scientifically proven medical or surgical treatment. Prospective studies from the 1990s onward have demonstrated that most growth of spontaneous ICH occurs within the first 2 to 3 hours and that growth of ICH and resulting volumes of ICH and intraventricular hemorrhage are modifiable factors that can improve outcome. Trials focusing on early treatment of elevated blood pressure have suggested a target systolic blood pressure of 140 mm Hg, but none of the trials were positive by their primary end point. Hemostatic agents to decrease bleeding in spontaneous ICH have included desmopressin, tranexamic acid, and rFVIIa (recombinant factor VIIa) without clear benefit, and platelet infusions which were associated with harm. Hemostatic agents delivered within the first several hours have the greatest impact on growth of ICH and potentially on outcome. No large Phase III surgical ICH trial has been positive by primary end point, but pooled analyses suggest that earlier ICH removal is more likely to be beneficial. Recent trials emphasize maximization of clot removal and minimizing brain injury from the surgical approach. The future of ICH therapy must focus on delivery of medical and surgical therapies as soon as possible if we are to improve outcomes.

Imaging-Based Outcome Prediction of Acute Intracerebral Hemorrhage

We hypothesized that imaging-only-based machine learning algorithms can analyze non-enhanced CT scans of patients with acute intracerebral hemorrhage (ICH). This retrospective multicenter cohort study analyzed 520 non-enhanced CT scans and clinical data of patients with acute spontaneous ICH. Clinical outcome at hospital discharge was dichotomized into good outcome and poor outcome using different modified Rankin Scale (mRS) cut-off values. Predictive performance of a random forest machine learning approach based on filter- and texture-derived high-end image features was evaluated for differentiation of functional outcome at mRS 2, 3, and 4. Prediction of survival (mRS ≤ 5) was compared to results of the ICH Score. All models were tuned, validated, and tested in a nested 5-fold cross-validation approach. Receiver-operating-characteristic area under the curve (ROC AUC) of the machine learning classifier using image features only was 0.80 (95% CI [0.77; 0.82]) for predicting mRS ≤ 2, 0.80 (95% CI [0.78; 0.81]) for mRS ≤ 3, and 0.79 (95% CI [0.77; 0.80]) for mRS ≤ 4. Trained on survival prediction (mRS ≤ 5), the classifier reached an AUC of 0.80 (95% CI [0.78; 0.82]) which was equivalent to results of the ICH Score. If combined, the integrated model showed a significantly higher AUC of 0.84 (95% CI [0.83; 0.86], P value <0.05). Accordingly, sensitivities were significantly higher at Youden Index maximum cut-offs (77% vs. 74% sensitivity at 76% specificity, P value <0.05). Machine learning–based evaluation of quantitative high-end image features provided the same discriminatory power in predicting functional outcome as multidimensional clinical scoring systems. The integration of conventional scores and image features had synergistic effects with a statistically significant increase in AUC.

Recent advances in iron homeostasis and regulation - a focus on epigenetic regulation and stroke

Iron is an element with redox properties. It is active sites of many enzymes and plays an important role in various cellular and biological functions including ATP production and DNA synthesis. However, as a redox element, iron promotes free radical generation and lipid peroxidation, causing oxidative damage and cell death. Iron-mediated oxidation is a central player in ferroptosis, a type of cell death process that is different from apoptosis and necrosis. Thus, iron metabolism and homeostasis are sophisticatedly regulated. There has been exciting progress in understanding iron metabolism and regulation since hepcidin was recognized as the central regulator of iron homeostasis. Hepcidin mainly regulates the iron export function of the ferrous iron permease, ferroportin, which is the only known iron exporter expressed by mammalian cells. Particularly, epigenetic regulation has been a recent focus on iron homeostasis. Epigenetic phenomena have been demonstrated to modulate key proteins including hepcidin in iron metabolism. Here, we review the rapid progress in recent years in understanding molecular mechanisms of iron homeostasis with a focus on epigenetic regulation of hepcidin, ferritin, and ferroptosis. Interactions between methionine oxidation and iron is also discussed. Furthermore, many studies have suggested that the severity of neuronal damage after stroke is proportional to the magnitude of brain iron accumulation. Recent discoveries regarding iron metabolism in stroke is briefly discussed. Understanding the underlying mechanism in iron regulation could provide insight into the treatment of various intractable diseases including stroke.

Optimized lactoferrin as a highly promising treatment for intracerebral hemorrhage: Pre-clinical experience

Intracerebral hemorrhage (ICH) is the deadliest form of stroke for which there is no effective treatment, despite an endless number of pre-clinical studies and clinical trials. The obvious therapeutic target is the neutralization of toxic products of red blood cell (RBC) lysis that lead to cytotoxicity, inflammation, and oxidative damage. We used rigorous approaches and translationally relevant experimental ICH models to show that lactoferrin-(LTF)-based monotherapy is uniquely robust in reducing brain damage after ICH. Specifically, we designed, produced, and pharmacokinetically/toxicologically characterized an optimized LTF, a fusion of human LTF and the Fc domain of human IgG (FcLTF) that has a 5.8-fold longer half-life in the circulation than native LTF. Following dose-optimization studies, we showed that FcLTF reduces neurological injury caused by ICH in aged male/female mice, and in young male Sprague Dawley (SD) and spontaneously hypertensive rats (SHR). FcLTF showed a remarkably long 24-h therapeutic window. In tissue culture systems, FcLTF protected neurons from the toxic effects of RBCs and promoted microglia toward phagocytosis of RBCs and dead neurons, documenting its pleotropic effect. Our findings indicate that FcLTF is safe and effective in reducing ICH-induced damage in animal models used in this study.

Translational Intracerebral Hemorrhage Research: Has Current Neuroprotection Research ARRIVEd at a Standard for Experimental Design and Reporting?

One major aim of preclinical intracerebral hemorrhage (ICH) research is to develop and test potential neuroprotectants. Published guidelines for experimental design and reporting stress the importance of clearly and completely reporting results and methodological details to ensure reproducibility and maximize information availability. The current review has two objectives: first, to characterize current ICH neuroprotection research and, second, to analyze aspects of translational design in preclinical ICH studies. Translational design is the adoption and reporting of experimental design characteristics that are thought to be clinically relevant and critical to reproducibility in animal studies (e.g., conducting and reporting experiments according to the STAIR and ARRIVE guidelines, respectively). Given that ICH has no current neuroprotective treatments and an ongoing reproducibility crisis in preclinical research, translational design should be considered by investigators. We conducted a systematic review of ICH research from 2015 to 2019 using the PubMed database. Our search returned 281 published manuscripts studying putative neuroprotectants in animal models. Contemporary ICH research predominantly uses young, healthy male rodents. The collagenase model is the most commonly used. Reporting of group sizes, blinding, and randomization are almost unanimous, but group size calculations, mortality and exclusion criteria, and animal model characteristics are infrequently reported. Overall, current ICH neuroprotection research somewhat aligns with experimental design and reporting guidelines. However, there are areas for improvement. Because failure to consider translational design is associated with inflation of effect sizes (and possibly hindered reproducibility), we suggest that researchers, editors, and publishers collaboratively consider enhanced adherence to published guidelines.

Noncontrast CT markers of intracerebral hemorrhage expansion and poor outcome: A meta-analysis

OBJECTIVE

To provide precise estimates of the association between noncontrast CT (NCCT) markers, hematoma expansion (HE), and functional outcome in patients presenting with intracerebral hemorrhage (ICH) through a systematic review and meta-analysis.

METHODS

We searched PubMed for English-written observational studies or randomized controlled trials reporting data on NCCT markers of HE and outcome in spontaneous ICH including at least 50 subjects. The outcomes of interest were HE (hematoma growth >33%, >33% and/or >6 mL, >33% and/or >12.5 mL), poor functional outcome (modified Rankin Scale 3-6 or 4-6) at discharge or at 90 days, and mortality. We pooled data in random-effects models and extracted cumulative odds ratio (OR) for each NCCT marker.

RESULTS

We included 25 eligible studies (n = 10,650). The following markers were associated with increased risk of HE and poor outcome, respectively: black hole sign (OR = 3.70, 95% confidence interval [CI] = 1.42-9.64 and OR = 5.26, 95% CI = 1.75-15.76), swirl sign (OR = 3.33, 95% CI = 2.42-4.60 and OR = 3.70; 95% CI = 2.47-5.55), heterogeneous density (OR = 2.74; 95% CI = 1.71-4.39 and OR = 2.80; 95% CI = 1.78-4.39), blend sign (OR = 3.49; 95% CI = 2.20-5.55 and OR = 2.21; 95% CI 1.16-4.18), hypodensities (OR = 3.47; 95% CI = 2.18-5.50 and OR = 2.94; 95% CI = 2.28-3.78), irregular shape (OR = 2.01, 95% CI = 1.27-3.19 and OR = 3.43; 95% CI = 2.33-5.03), and island sign (OR = 7.87, 95% CI = 2.17-28.47 and OR = 6.05, 95% CI = 4.44-8.24).

CONCLUSION

Our results suggest that multiple NCCT ICH shape and density features, with different effect size, are important markers for HE and clinical outcome and may provide useful information for future randomized controlled trials.

Safety and Use of MLC601/MLC901 (NeuroAiDTM) in Primary Intracerebral Hemorrhage: A Cohort Study from the NeuroAiD Safe Treatment Registry

Background: MLC601/MLC901 (NeuroAiD™) is a combination of natural products shown to be safe and to aid neurological recovery after brain injuries, especially ischemic stroke. Few studies have investigated NeuroAiD in primary intracerebral hemorrhage (ICH). The NeuroAiD Safe Treatment (NeST) Registry explores NeuroAiD use in the real-world setting. This cohort study aimed to assess its use and safety in ICH. Methods: The online NeST Registry of subjects with ICH given NeuroAiD prospectively collected clinical data at baseline and monthly visits (V) 1 to 3. Outcome measures included compliance, side effects, Glasgow Coma Scale (GCS), National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), and Short Orientation-Memory-Concentration Test (SOMCT). Results: Sixty-six subjects were included. NeuroAiD was well-tolerated with fair compliance over three months. Two non-serious side effects were reported. Mean scores significantly improved on all outcome scales. The proportion of subjects with favorable outcomes significantly improved from baseline to V3: NIHSS 0–4, from 12% to 59% (p < 0.0001); GCS 13–15, from 64% to 88% (p = 0.007); mRS 0–1, from 9% to 37% (p = 0.004); and SOMCT score 0–8, from 44% to 68% (p = 0.029). Conclusions: NeuroAiD in the real-world setting was safe and showed potential for a sustained positive effect on neurological recovery after ICH.

Circulating TIMP-1 is associated with hematoma volume in patients with spontaneous intracranial hemorrhage

Matrix metalloproteinases (MMPs) are proteolytic zinc-endopeptidases regulated by tissue Inhibitors of matrix metalloproteinases (TIMPs). We evaluated the potential of MMPs and TIMPs as clinical tools for Intracranial Haemorrhage (ICH). Spontaneous non-traumatic ICH patients were recruited from two hospitals: Complejo Hospitalario de Navarra (CHN = 29) and Vall d´Hebron (VdH = 76). Plasmatic levels of MMP-1, -2, -7, -9, -10 and TIMP-1 and their relationship with clinical, radiological and functional variables were evaluated. We further studied the effect of TIMP-1 (0.05-0.2 mg/Kg) in an experimental tail-bleeding model. In CHN, TIMP-1 was associated with admission-hematoma volume and MMP-7 was elevated in patients with deep when compared to lobar hematoma. In VdH, admission-hematoma volume was associated with TIMP-1 and MMP-7. When data from both hospitals were combined, we observed that an increase in 1 ng/ml in TIMP-1 was associated with an increase of 0.14 ml in haemorrhage (combined β = 0.14, 95% CI = 0.08-0.21). Likewise, mice receiving TIMP-1 (0.2 mg/Kg) showed a shorter bleeding time (p < 0.01). Therefore, the association of TIMP-1 with hematoma volume in two independent ICH cohorts suggests its potential as ICH biomarker. Moreover, increased TIMP-1 might not be sufficient to counterbalance MMPs upregulation indicating that TIMP-1 administration might be a beneficial strategy for ICH.

Evaluating Hematoma Expansion Scores in Acute Spontaneous Intracerebral Hemorrhage: A Systematic Scoping Review

Background and Purpose- In acute spontaneous intracerebral hemorrhage, multiple hematoma expansion scores have been proposed for use in clinical trial environments. We performed a systematic scoping review to identify all existing hematoma expansion scores and describe their development, validation, and relative performance. Methods- Two reviewers searched MEDLINE, PUBMED, EMBASE, and CENTRAL (Cochrane Central Register of Controlled Trials) for studies that derived or validated a hematoma expansion prediction score in adults presenting with spontaneous intracerebral hemorrhage. A descriptive analysis of the extracted data was performed, focusing on score development techniques and predictive capabilities. Results- Of the 14 434 records retrieved, 15 studies met inclusion criteria and 10 prediction scores were identified. Validation analysis using independent samples was performed in 9 studies on 5 scores. All derivation studies reported high performance with C statistics ranging from 0.72 to 0.93. In validation, the C-statistic range was broader with studies reporting 0.62 to 0.77. For every score, the risk of expansion increased with each point increase, although patients with high scores were rare. Conclusions- At present, 10 hematoma expansion scores have been developed, of which 5 have been externally validated. Real-world performance in validation studies was lower than performance in derivation studies. Data from the current literature are insufficient to support a meaningful meta-analysis.

A combination of Deferoxamine mesylate and minimally invasive surgery with hematoma lysis for evacuation of intracerebral hemorrhage

Intracerebral hemorrhage is associated with significant morbidity and mortality. Some clinical trials demonstrated a trend towards benefit with surgical evacuation of intracerebral hemorrhage, without strong statistically significant results. Subsequent studies focused on minimally invasive techniques. Improved outcomes were more likely with surgical reduction of intracerebral hemorrhage volume to ≤15 mL. Deferoxamine is currently being evaluated as a therapeutic tool in intracerebral hemorrhage with promising results. There continues to be a lack of level I evidence supporting medical and surgical tools for intracerebral hemorrhage evacuation. Could a combination of minimally invasive surgery with hematoma lysis and Deferoxamine result in more effective hematoma evacuation?

Standards for Detecting, Interpreting, and Reporting Noncontrast Computed Tomographic Markers of Intracerebral Hemorrhage Expansion

Significant hematoma expansion (HE) affects one-fifth of people within 24 hours after acute intracerebral hemorrhage (ICH), and its prevention is an appealing treatment target. Although the computed tomography (CT)-angiography spot sign predicts HE, only a minority of ICH patients receive contrast injection. Conversely, noncontrast CT (NCCT) is used to diagnose nearly all ICH, so NCCT markers represent a widely available alternative for prediction of HE. However, different NCCT signs describe similar features, with lack of consensus on the optimal image acquisition protocol, assessment, terminology, and diagnostic criteria. In this review, we propose practical guidelines for detecting, interpreting, and reporting NCCT predictors of HE. ANN NEUROL 2019;86:480-492.

Deferoxamine mesylate in patients with intracerebral haemorrhage (i-DEF): a multicentre, randomised, placebo-controlled, double-blind phase 2 trial

BACKGROUND

Iron from haemolysed blood is implicated in secondary injury after intracerebral haemorrhage. We aimed to assess the safety of the iron chelator deferoxamine mesylate in patients with intracerebral haemorrhage and to establish whether the drug merits investigation in a phase 3 trial.

METHODS

We did a multicentre, futility-design, randomised, placebo-controlled, double-blind, phase 2 trial at 40 hospitals in Canada and the USA. Adults aged 18-80 years with primary, spontaneous, supratentorial intracerebral haemorrhage were randomly assigned (1:1) to receive deferoxamine mesylate (32 mg/kg per day) or placebo (saline) infusions for 3 consecutive days within 24 h of haemorrhage onset. Randomisation was done via a web-based trial-management system centrally in real time, and treatment allocation was concealed from both participants and investigators. The primary outcome was good clinical outcome, which was defined as a modified Rankin Scale score of 0-2 at day 90. We did a futility analysis: if the 90% upper confidence bound of the absolute risk difference between the two groups in the proportion of participants with a good clinical outcome was less than 12% in favour of deferoxamine mesylate, then to move to a phase 3 efficacy trial would be futile. Primary outcome and safety data were analysed in the modified intention-to-treat population, comprising only participants in whom the study infusions were initiated. This trial is registered with ClinicalTrials.gov, number NCT02175225, and is completed.

FINDINGS

We recruited 294 participants between Nov 23, 2014, and Nov 10, 2017. The modified intention-to-treat population consisted of 144 patients assigned to the deferoxamine mesylate group and 147 assigned to the placebo group. At day 90, among patients with available data for the primary outcome, 48 (34%) of 140 participants in the deferoxamine mesylate group, and 47 (33%) of 143 patients in the placebo group, had modified Rankin Scale scores of 0-2 (adjusted absolute risk difference 0·6% [90% upper confidence bound 6·8%]). By day 90, 70 serious adverse events were reported in 39 (27%) of 144 patients in the deferoxamine mesylate group, and 78 serious adverse events were reported in 49 (33%) of 147 patients in the placebo group. Ten (7%) participants in the deferoxamine mesylate and 11 (7%) in the placebo group died. None of the deaths were judged to be treatment related.

INTERPRETATION

Deferoxamine mesylate was safe. However, the primary result showed that further study of the efficacy of deferoxamine mesylate with anticipation that the drug would significantly improve the chance of good clinical outcome (ie, mRS score of 0-2) at day 90 would be futile.

FUNDING

US National Institutes of Health and US National Institute of Neurological Disorders and Stroke.

Iron Pathophysiology in Stroke

Ischemic and hemorrhagic stroke are the common types of stroke that lead to brain injury neurological deficits and mortality. All forms of stroke remain a serious health issue, and there is little successful development of drugs for treating stroke. Incomplete understanding of stroke pathophysiology is considered the main barrier that limits this research progress. Besides mitochondria and free radical-producing enzymes, labile iron is an important contributor to oxidative stress. Although iron regulation and metabolism in cerebral stroke are not fully understood, much progress has been achieved in recent years. For example, hepcidin has recently been recognized as the principal regulator of systemic iron homeostasis and a bridge between inflammation and iron regulation. This review discusses recent research progress in iron pathophysiology following cerebral stroke, focusing molecular regulation of iron metabolism and potential treatment targets.

Regulation of Neurological Devices and Neurointerventional Endovascular Approaches for Acute Ischemic Stroke

The United States Food and Drug Administration (FDA) Center for Devices and Radiological Health (CDRH) is charged with ensuring patients in the US have timely access to high-quality, safe, and effective medical devices of public health importance. Within CDRH, the Division of Neurological and Physical Medicine Devices reviews medical technologies that interface with the central and peripheral nervous system (neurotechnologies), including neurointerventional medical devices that are used in the treatment of stroke. Endovascular treatments have demonstrated recent advances in reaching the marketplace and providing more options for patients with acute ischemic stroke and intracranial aneurysms specifically. Depending upon the pathway chosen for regulatory approval, and the evidentiary standard for different regulatory pathways, neurotechnologies can have well-established safety and effectiveness profiles, varying degrees of scientific and clinical uncertainty regarding safety and effectiveness, or when a humanitarian use exists, need only demonstrate a probable benefit and safety to the patient so potentially life-saving treatments can reach the marketplace. Reperfusion therapies have had specific advances in the treatment of stroke patients that originally had limited or no treatment options and for preventative treatments in providing care to patients with intracranial aneurysms to avoid potentially more catastrophic outcomes. Collaboration in multiple forums and environments will be important to continue to foster the neurointerventional technology sector and positively impact clinical medicine, from diagnosing and treating a neurological disorder, to potentially altering the progression of disease, and in many ways, contemporary approved devices have brought a new sense of hope and optimism that serious and otherwise disabling neurological diseases can be treated and in many cases cured with modern therapy. We present here the scope of FDA’s regulatory landscape for neurological devices and neurointerventional endovascular approaches for acute ischemic stroke; this is essential information for those seeking to successfully translate medical device neurotechnologies for patient and consumer use.