Clearance of Neutrophils From ICH-Affected Brain by Macrophages Is Beneficial and Is Assisted by Lactoferrin and CD91.

BACKGROUND: Within hours after intracerebral hemorrhage (ICH) onset, masses of polymorphonuclear neutrophils (PMNs) infiltrate the ICH-affected brain. After degranulation involving controlled release of many toxic antimicrobial molecules, the PMNs undergo rapid apoptosis and then are removed by phagocytic microglia/macrophages (MΦ) through a process called efferocytosis. Effective removal of PMNs may limit secondary brain damage and inflammation; however, the molecular mechanisms governing these cleanup activities are not well understood. We propose that scavenger receptor CD91 on myeloid phagocytes especially in presence of CD91 ligand, LTF (lactoferrin, protein abundant in PMNs), plays an important role in clearance of dead apoptotic PMNs (ANs). METHODS: Mice/rats were subjected to an autologous blood injection model of ICH. Primary cultured microglia were used to assess phagocytosis of ANs. Immunohistochemistry was employed to assess CD91 expression and PMN infiltration. CD91 knockout mice selectively in myeloid phagocytes (Mac-CD91-KO) were used to establish the CD91/LTF function in phagocytosis and in reducing ICH-induced injury, as assessed using behavioral tests, hematoma resolution, and oxidative stress. RESULTS: Masses of PMNs are found in ICH-affected brain, and they contain LTF. MΦ at the outer border of hematoma are densely packed, expressing CD91 and phagocytosing ANs. Microglia deficient in CD91 demonstrate defective phagocytosis of ANs, and mice deficient in CD91 (Mac-CD91-KO) subjected to ICH injury have increased neurological dysfunction that is associated with impaired hematoma resolution (hemoglobin and iron clearance) and elevated oxidative stress. LTF that normally ameliorates ICH injury in CD91-proficient control mice shows reduced therapeutic effects in Mac-CD91-KO mice. CONCLUSIONS: Our study suggests that CD91 plays a beneficial role in improving ANs phagocytosis and ultimately post-ICH outcome and that the beneficial effect of LTF in ICH is in part dependent on presence of CD91 on MΦ.

Hemorrhagic Transformation in Noncardioembolic Acute Ischemic Stroke: MRI Analysis From PACIFIC-STROKE.

BACKGROUND: In the phase 2 PACIFIC-STROKE trial (Proper Dosing and Safety of the Oral FXIa Inhibitor BAY 2433334 in Patients Following Acute Noncardioembolic Stroke), asundexian, an oral factor XIa inhibitor, did not increase the risk of hemorrhagic transformation (HT). In this secondary analysis, we aimed to investigate the frequency, types, and risk factors of HT on brain magnetic resonance imaging (MRI). METHODS: This was a secondary analysis of the PACIFIC-STROKE trial. Patients with mild-to-moderate acute noncardioembolic ischemic stroke were randomly assigned to asundexian or placebo plus guideline-based antiplatelet therapy. Brain MRIs were required at baseline (≤120 hours after stroke onset) and at 26 weeks or end-of-study. HT was defined using the Heidelberg classification and classified as early HT (identified on baseline MRI) or late HT (new HT by 26 weeks) based on iron-sensitive sequences. Multivariable logistic regression models were used to test factors that are associated with early HT and late HT, respectively. RESULTS: Of 1745 patients with adequate baseline brain MRI (mean age, 67 years; mean National Institutes of Health Stroke Scale score, 2.8), early HT at baseline was detected in 497 (28.4%). Most were hemorrhagic infarctions (hemorrhagic infarction type 1: 15.2%; HI2: 12.7%) while a few were parenchymal hematomas (parenchymal hematoma type 1: 0.4%; parenchymal hematoma type 2: 0.2%). Early HT was more frequent with longer symptom onset-to-MRI interval. Male sex, diabetes, higher National Institutes of Health Stroke Scale large (>15 mm) infarct size, cortical involvement by infarct, higher number of acute infarcts, presence of chronic brain infarct, cerebral microbleed, and chronic cortical superficial siderosis were independently associated with early HT in the multivariable logistic regression model. Of 1507 with follow-up MRI, HT was seen in 642 (42.6%) overall, including 361 patients (23.9%) with late HT (new HT: 306; increased grade of baseline HT: 55). Higher National Institutes of Health Stroke Scale, large infarct size, cortical involvement of infarct, and higher number of acute infarcts predicted late HT. CONCLUSIONS: About 28% of patients with noncardioembolic stroke had early HT, and 24% had late HT detectable by MRI. Given the high frequency of HT on MRI, more research is needed on how it influences treatment decisions and outcomes.

Optimum Baseline Clinical Severity Scale Cut Points for Prognosticating Intracerebral Hemorrhage: INTERACT Studies.

BACKGROUND: The optimal cut point of baseline National Institutes of Health Stroke Scale (NIHSS) and Glasgow Coma Scale scores for prognosticating acute intracerebral hemorrhage (ICH) is unknown. METHODS: Secondary analyses of participant data are from the INTERACT (Intensive Blood Pressure Reduction in Acute Intracerebral Hemorrhage Trials) 1 and 2 studies. Receiver operating characteristic analyses were used to compare the predictive performance of baseline NIHSS and Glasgow Coma Scale scores, ICH score, and max-ICH score. Optimal cut points for predicting 90-day clinical outcomes (death or major disability [defined as modified Rankin Scale scores 3-6], major disability [defined as modified Rankin Scale scores 3-5], and death alone) were determined using the Youden index. Logistic regression models were adjusted for age, sex, hematoma volume, and other known risk factors for poor prognosis. We validated our findings in the INTERACT1 database. RESULTS: There were 2829 INTERACT2 patients (age, 63.5±12.9 years; male, 62.9%; ICH volume, 10.96 [5.77-19.49] mL) included in the main analyses. The baseline NIHSS score (area under the curve, 0.796) had better prognostic utility for predicting death or major disability than the Glasgow Coma Scale score (area under the curve, 0.650) and ICH score (area under the curve, 0.674) and was comparable to max-ICH score (area under the curve, 0.789). Similar findings were observed when assessing the outcome of major disability. A cut point of 10 on baseline NIHSS optimally (sensitivity, 77.5%; specificity, 69.2%) predicted death or major disability (adjusted odds ratio, 4.50 [95% CI, 3.60-5.63]). The baseline NIHSS cut points that optimally predicted major disability and death alone were 10 and 12, respectively. The predictive effect of NIHSS≥10 for poor functional outcomes was consistent in all subgroups including age and baseline hematoma volume. Results were consistent when analyzed in the independent INTERACT1 validation database. CONCLUSIONS: In patients with mild-to-moderate ICH, a baseline NIHSS score of ≥10 was optimal for predicting poor outcomes at 90 days. Prediction based on baseline NIHSS is better than baseline Glasgow Coma Scale score. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT00226096 and NCT00716079.

Magnesium and Hematoma Expansion in Intracerebral Hemorrhage: A FAST-MAG Randomized Trial Analysis.

BACKGROUND: Observational studies suggest that magnesium may have hemostatic effects. FAST-MAG (Field Administration of Stroke Therapy-Magnesium) was a pragmatic clinical trial of magnesium sulfate administered prehospital for acute clinical stroke syndromes and included patients with intracerebral hemorrhage. Exploratory secondary analysis by the treatment group found no reduction in hematoma expansion (HE) associated with magnesium treatment in intracerebral hemorrhage but did not consider serum magnesium levels achieved. We analyzed FAST-MAG intracerebral hemorrhage data for associations between serum magnesium level, HE, and early neurological deterioration, accounting for groupwise biases. METHODS: HE was defined as hematoma volume increase ≥3 mL within 24 hours and early neurological deterioration as ≥1-point Glasgow Coma Scale decline from arrival to hospital day 4. Comparing treatment and placebo groups confirmed biased availability of neuroimaging data. Therefore, HE and neurological deterioration were analyzed and stratified by treatment and placebo groups using univariate tests and adjusted logistic regression. RESULTS: Spontaneous intracerebral hemorrhage was present in 381 patients. Placebo patients had fewer serial neuroimaging studies available (123 [65.4%] versus 145 [75.1%]; P=0.038). Necessary data were available in 104 magnesium- and 85 placebo-treated patients (age, 64.9 [13.0] years; 67.7% male). In the magnesium group, higher magnesium level was associated with less HE (adjusted odds ratio, 0.64 per mg/dL [95% CI, 0.42-0.93]) and less neurological deterioration (adjusted odds ratio, 0.54 per mg/dL [95% CI, 0.33-0.82]). In the placebo group, magnesium level was not associated with either HE or neurological deterioration. CONCLUSIONS: Magnesium may exhibit a hemostatic effect that was only observable in the FAST-MAG magnesium treatment group. Equipoise should be maintained, and specific trials are needed. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00059332.

Association Between Hematoma Volume and Risk of Subsequent Ischemic Stroke: A MISTIE III and ATACH-2 Analysis.

BACKGROUND: Nontraumatic intracerebral hemorrhage (ICH) is independently associated with a long-term increased risk of major arterial ischemic events. While the relationship between ICH location and ischemic risk has been studied, whether hematoma volume influences this risk is poorly understood. METHODS: We pooled individual patient data from the MISTIE III (Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation Phase 3) and the ATACH-2 (Antihypertensive Treatment of Acute Cerebral Hemorrhage-2) trials. The exposure was hematoma volume, treated as a continuous measure in the primary analysis, and dichotomized by the median in the secondary analyses. The outcome was a symptomatic, clinically overt ischemic stroke, adjudicated centrally within each trial. We evaluated the association between hematoma volume and the risk of an ischemic stroke using Cox regression analyses after adjustment for demographics, vascular comorbidities, and ICH characteristics. RESULTS: Of 1470 patients with ICH, the mean age was 61.7 (SD, 12.8) years, and 574 (38.3%) were female. The median hematoma volume was 17.3 mL (interquartile range, 7.2-35.7). During a median follow-up of 107 days (interquartile range, 91-140), a total of 30 ischemic strokes occurred, of which 22 were in patients with a median ICH volume of ≥17.3 mL and a cumulative incidence of 4.6% (95% CI, 3.1-7.1). Among patients with a median ICH volume <17.3 mL, there were 8 ischemic strokes with a cumulative incidence of 3.1% (95% CI, 1.7-6.0). In primary analyses using adjusted Cox regression models, ICH volume was associated with an increased risk of ischemic stroke (hazard ratio, 1.02 per mL increase [95% CI, 1.01-1.04]). In secondary analyses, ICH volume of ≥17.3 mL was associated with an increased risk of ischemic stroke (hazard ratio, 2.5 [95% CI, 1.1-7.2]), compared with those with an ICH volume <17.3 mL. CONCLUSIONS: In a heterogeneous cohort of patients with ICH, initial hematoma volume was associated with a heightened short-term risk of ischemic stroke.

ARISE I Consensus Statement on the Management of Chronic Subdural Hematoma.

ARISE (Aneurysm/AVM/cSDH Roundtable Discussion With Industry and Stroke Experts) organized a one-and-a-half day meeting and workshop and brought together representatives from academia, industry, and government to discuss the most promising approaches to improve outcomes for patients with chronic subdural hematoma (cSDH). The emerging role of middle meningeal artery embolization in clinical practice and the design of current and potential future trials were the primary focuses of discussion. Existing evidence for imaging, indications, agents, and techniques was reviewed, and areas of priority for study and key questions surrounding the development of new and existing treatments for cSDH were identified. Multiple randomized, controlled trials have met their primary efficacy end points, providing high-level evidence that middle meningeal artery embolization is a potent adjunctive therapy to the standard (surgical and nonsurgical) management of neurologically stable cSDH patients in terms of reducing rates of disease recurrence. Pooled data analyses following the formal conclusion and publication of these trials will form a robust foundation upon which guidelines can be strengthened for cSDH treatment modalities and optimal patient selection, as well as delineate future lines of investigation.

Influence of Time to Achieve Target Systolic Blood Pressure on Outcome After Intracerebral Hemorrhage: The Blood Pressure in Acute Stroke Collaboration.

OBJECTIVE: To investigate whether an earlier time to achieving and maintaining systolic blood pressure (SBP) at 120 to 140 mm Hg is associated with favorable outcomes in a cohort of patients with acute intracerebral hemorrhage. METHODS: We pooled individual patient data from randomized controlled trials registered in the Blood Pressure in Acute Stroke Collaboration. Time was defined as time form symptom onset plus the time (hour) to first achieve and subsequently maintain SBP at 120 to 140 mm Hg over 24 hours. The primary outcome was functional status measured by the modified Rankin Scale at 90 to 180 days. A generalized linear mixed models was used, with adjustment for covariables and trial as a random effect. RESULTS: A total of 5761 patients (mean age, 64.0 [SD, 13.0], 2120 [36.8%] females) were included in analyses. Earlier SBP control was associated with better functional outcomes (modified Rankin Scale score, 3-6; odds ratio, 0.98 [95% CI, 0.97-0.99]) and a significant lower risk of hematoma expansion (0.98, 0.96-1.00). This association was stronger in patients with bigger baseline hematoma volume (>10 mL) compared with those with baseline hematoma volume ≤10 mL (0.006 for interaction). Earlier SBP control was not associated with cardiac or renal adverse events. CONCLUSIONS: Our study confirms a clear time relation between early versus later SBP control (120-140 mm Hg) and outcomes in the one-third of patients with intracerebral hemorrhage who attained sustained SBP levels within this range. These data provide further support for the value of early recognition, rapid transport, and prompt initiation of treatment of patients with intracerebral hemorrhage.

Mas receptor activation facilitates innate hematoma resolution and neurological recovery after hemorrhagic stroke in mice.

BACKGROUND: Intracerebral hemorrhage (ICH) is a devastating neurological disease causing severe sensorimotor dysfunction and cognitive decline, yet there is no effective treatment strategy to alleviate outcomes of these patients. The Mas axis-mediated neuroprotection is involved in the pathology of various neurological diseases, however, the role of the Mas receptor in the setting of ICH remains to be elucidated. METHODS: C57BL/6 mice were used to establish the ICH model by injection of collagenase into mice striatum. The Mas receptor agonist AVE0991 was administered intranasally (0.9 mg/kg) after ICH. Using a combination of behavioral tests, Western blots, immunofluorescence staining, hematoma volume, brain edema, quantitative-PCR, TUNEL staining, Fluoro-Jade C staining, Nissl staining, and pharmacological methods, we examined the impact of intranasal application of AVE0991 on hematoma absorption and neurological outcomes following ICH and investigated the underlying mechanism. RESULTS: Mas receptor was found to be significantly expressed in activated microglia/macrophages, and the peak expression of Mas receptor in microglia/macrophages was observed at approximately 3-5 days, followed by a subsequent decline. Activation of Mas by AVE0991 post-treatment promoted hematoma absorption, reduced brain edema, and improved both short- and long-term neurological functions in ICH mice. Moreover, AVE0991 treatment effectively attenuated neuronal apoptosis, inhibited neutrophil infiltration, and reduced the release of inflammatory cytokines in perihematomal areas after ICH. Mechanistically, AVE0991 post-treatment significantly promoted the transformation of microglia/macrophages towards an anti-inflammatory, phagocytic, and reparative phenotype, and this functional phenotypic transition of microglia/macrophages by Mas activation was abolished by both Mas inhibitor A779 and Nrf2 inhibitor ML385. Furthermore, hematoma clearance and neuroprotective effects of AVE0991 treatment were reversed after microglia depletion in ICH. CONCLUSIONS: Mas activation can promote hematoma absorption, ameliorate neurological deficits, alleviate neuron apoptosis, reduced neuroinflammation, and regulate the function and phenotype of microglia/macrophages via Akt/Nrf2 signaling pathway after ICH. Thus, intranasal application of Mas agonist ACE0991 may provide promising strategy for clinical treatment of ICH patients.

A single-center experience of type B aortic intramural hematoma.

OBJECTIVE: The outcomes of the best medical treatment (BMT) and intervention treatment (INT) in a single-center experience were reported in type B intramural hematoma (IMH). METHODS: From February 2015 to February 2021, a total of 195 consecutive patients with type B IMH were enrolled in the study. The primary end point was mortality, and the secondary end points included clinical and imaging outcomes. The clinical outcomes were aortic-related death, retrograde type A aortic dissection, stent graft-induced new entry tear, endoleak, and reintervention. The imaging outcome was evaluated through the latest follow-up computed tomography angiography, which included aortic rupture, aortic dissection, aortic aneurysm, rapid growth of aortic diameter, newly developed or enlarged penetrating aortic ulcer or ulcer-like projection (ULP) and increased aortic wall thickness. Kaplan-Meier curves were used to assess the association between different treatments. RESULTS: Among the enrolled patients, 115 received BMT, and 80 received INT. There was no significant difference in early (1.7% vs 2.5%; P = 1.00) and midterm all-cause death (8.3% vs 5.2%; P = .42) between the BMT and INT groups. However, patients who underwent INT were at risk of procedure-related complications such as stent graft-induced new entry tear and endoleaks. The INT group was associated with a profound decrease in the risk of ULP, including newly developed ULP (4.3% vs 26.9%; P < .05), ULP enlargement (6.4% vs 31.3%; P < .05), and a lower proportion of high-risk ULP (10.9% vs 45.6%; P < .05). Although there was no significant difference in the incidence of IMH regression between the two groups, the maximum diameter of the descending aorta in patients receiving INT was larger compared with those treated with BMT. CONCLUSIONS: Based on our limited experience, patients with type B IMH treated with BMT or INT shared similar midterm clinical outcome. Patients who underwent INT may have a decreased risk of ULPs, but a higher risk of procedure-related events and patients on BMT should be closely monitored for ULP progression.

Natural history and long-term outcomes of medically managed Type B intramural hematoma.

OBJECTIVE: Type B intramural hematoma (IMH) is often managed medically, yet may progress to dissection, aneurysmal dilation, or rupture. The aim of this study was to report the natural history of medically managed Type B IMH, and factors associated with progression. METHODS: We reviewed patients with medically managed Type B IMH between January 1995 to December 2022 at a single center. Any patients with immediate surgical or endovascular intervention were excluded. Demographic profiles, comorbidities, imaging, and follow-up details were reviewed. Patients were divided into two groups: Group 1 had isolated IMH, and Group 2 had IMH along with aneurysm or dissection at the time of presentation. On follow-up, progression was defined as degeneration to aneurysm/dissection or increase in the thickness of IMH in Group 1. In Group 2, progression was an increase in the size of aneurysm or development of new dissection. RESULTS: Of 104 patients with Type B IMH during the study period, 92 were medically managed. The median age was 77 years, and 45 (48.9%) were females. Comorbidities included hypertension (83.7%), hypercholesterolemia (44.6%), and active smoking (47.8%). Mean Society for Vascular Surger comorbidity score was 6.3. Mean IMH thickness and aortic diameter at presentation were 8.9 mm and 38.3 mm, respectively. Median follow-up was 55 months. Overall survival at 1 year and 5 years was 85.8% and 61.9%, respectively. During follow-up, 19 patients (20.7%) required intervention, more common in Group 2 (Group 1, 8/66; 12.3% vs Group 2, 11/26; 42.3%; P = .001). This resulted in higher freedom from intervention in Group 1 at 1 year (93.5% vs 62.7%) and 5 years (87.5% vs 51.1%; P < .001). Indication for intervention was dissection (n = 4), aneurysm (n = 12), and progression of IMH (n = 3). In Group 1, progression was seen in 25 (37.9%), three (4.5%) remained stable, 29 (43.9%) had complete resolution of IMH, and nine patients were lost to follow-up. In Group 2, 11 patients (42.3%) had progression, seven (26.9%) remained stable, and eight were lost to follow-up. IMH thickness at presentation >7.2 mm is associated with both increased odds of progression (odds ratio, 3.3; 95% confidence interval, 1.2-11.1; P = .03) and intervention (odds ratio, 5.5; 95% confidence interval, 1.3-36.9; P = .03) during the follow-up. CONCLUSIONS: Although many patients with Type B IMH managed medically stabilize or regress, progression or need for intervention can occur in up to 40% of cases. This is associated with the presence of aneurysm, dissection, and IMH thickness. Long-term follow-up is mandatory as late interventions occur, particularly for higher risk patients.