Current neurovascular research最新文献

Introduction: Endovascular treatment (EVT) performed in the early time window has been shown to decrease the incidence of malignant middle cerebral artery infarction (MMI). However, the incidence of MMI in patients undergoing EVT during the late time window is unclear. This study aimed to investigate the prevalence of MMI in patients undergoing late EVT and compare it with that in patients undergoing early EVT.

Methods: We retrospectively analyzed consecutive patients with anterior large vessel occlusion stroke who underwent EVT at Xuanwu Hospital between January 2013 and June 2021. Eligible patients were divided into early EVT (within 6 h) and late EVT (6-24 h) groups according to the time from their stroke onset to puncture and compared. The occurrence of MMI post-EVT was the primary outcome.

Results: A total of 605 patients were recruited, of whom 300 (50.4%) underwent EVT within 6 h and 305 (49.6%) underwent EVT within 6-24 h. A total of 119 patients (19.7%) developed MMI. 68 patients (22.7%) in the early EVT group and 51 patients (16.7 %) in the late EVT group developed MMI (p = 0.066). After adjusting for covariate variables, late EVT was independently associated with a lower incidence of MMI (odds ratio, 0.404; 95% confidence interval, 0.242-0.675; p = 0.001).

Conclusion: MMI is not an uncommon phenomenon in the modern thrombectomy era. Compared with the early time window, patients selected by stricter radiological criteria to undergo EVT in the late time window are independently associated with a lower incidence of MMI.

Background and objective: The potential impact of rebleeding and Delayed Cerebral Ischemia (DCI) on long-term survival in patients with aneurysmal subarachnoid hemorrhage (aSAH) remained unclear. This study aimed to investigate whether DCI and rebleeding increase the risk of long-term all-cause mortality in patients with aSAH who survived the follow-up period of one year.

Methods: We retrospectively collected data on patients with atraumatic aSAH who were still alive 12 months after aSAH occurrence between December 2013 and June 2019 from the electronic health system. Patients were then classified by the occurrence of rebleeding or DCI during hospitalization. Death records were obtained from an administrative database, the Chinese Household Registration Administration System, until April 20, 2021. Multivariable Cox proportional hazards models were used to compare overall survival in different groups. Sensitivity analysis was performed with propensity-score matching (PSM).

Results: A total of 2,607 patients were alive one year after aSAH. The crude annual death rate from any cause among patients who had rebleeding (7.2 per 100 person-years) and patients who had DCI (3.7 per 100 person-years) during hospitalization was higher than that of patients with neither event (2.1 per 100 person-years). Multivariate analysis showed that rebleeding is an independent risk factor for long-term mortality (adjusted hazard ratio (aHR), 2.37; 95% confidence interval (CI), 1.47- 3.81). DCI was an independent prognostic factor of poorer overall survival (aHR, 2.09; 95% CI, 1.54-2.84).

Conclusion: Amongst patients alive one year after aSAH, rebleeding and DCI during hospitalization were independently associated with higher rates of long-term mortality.

Background: Previous studies have demonstrated that statins can relieve inflammatory brain injury after intracerebral hemorrhage (ICH), but the mechanisms remain poorly characterized. This study aims to test whether simvastatin exerts an anti-inflammatory effect by regulating the proresolving mediators.

Methods: First, male Sprague-Dawley rats had an injection of 200 μL autologous blood. Then, rats were randomly divided into groups treated with simvastatin (i.p. 2 mg/kg) or vehicle. Next, all rats underwent pro-resolving mediator lipoxin A4 (LXA4) level detection, flow cytometric, immunofluorescence, brain edema measurement, neurological scoring and western blot analysis.

Results: We found that simvastatin significantly increased the plasma level of LXA4, an endogenous formyl-peptide receptor 2 (FPR2) agonist, in the early stage of ICH. Consistent with the effect of simvastatin, exogenous LXA4 administration also promoted apoptosis of the circulating neutrophils, reduced neutrophils brain infiltration, and ameliorated inflammatory brain injury after ICH. In addition, similar to simvastatin, exogenous LXA4 markedly decreased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK) and the apoptosis-related proteins myeloid cell leukemia 1(Mcl-1)/Bax ratio (a decreased ratio represents the induction of apoptosis) in circulating neutrophils isolated from ICH rats. Notably, all of the aforementioned effects of simvastatin on ICH were significantly abolished by Boc-2, a selective antagonist of FPR2. Moreover, simvastatin led to a similar Mcl-1/Bax ratio reduction as SB203580 (a p38 MAPK inhibitor), but it was abolished by P79350 (a p38 MAPK agonist).

Conclusion: Collectively, these results suggest that simvastatin ameliorates ICH-mediated inflammatory brain injury, possibly by upregulating the level of pro-resolving mediator LXA4 and further stimulating the FPR2/p38 MAPK signaling pathway.

Background: Uric acid (UA) has both antioxidative and pro-oxidative properties. The study aimed to investigate the relationship between serum UA and hemorrhagic transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke.

Methods: The patients undergoing intravenous thrombolysis from two hospitals in China were retrospectively analyzed. HT was evaluated using computed tomography images reviewed within 24- 36h after thrombolysis. Symptomatic intracranial hemorrhage (sICH) was defined as HT accompanied by worsening neurological function. Multivariate logistic regression and spline regression models were performed to explore the relationship between serum UA levels and the risk of HT and sICH.

Results: Among 503 included patients, 60 (11.9%) were diagnosed with HT and 22 (4.4%) developed sICH. Patients with HT had significant lower serum UA levels than those without HT (245 [214-325 vs. 312 [256-370] μmol/L, p < 0.001). Multivariable logistic regression analysis indicated that patients with higher serum UA levels had a lower risk of HT (OR per 10-μmol/L increase 0.96, 95%CI 0.92-0.99, p = 0.015). Furthermore, multiple-adjusted spline regression models showed a Ushaped association between serum UA levels and HT (p < 0.001 for non-linearity). Similar results were present between serum UA and sICH. Restricted cubic spline models predicted the lowest risk of HT and sICH when the serum UA levels were 386μmol/L.

Conclusion: The data show the U-shaped relationship between serum UA levels and the risk of HT and sICH after intravenous thrombolysis.

Objective: To our knowledge, no previous studies have investigated the impact of stroke severity on the smoking paradox after intravenous thrombolysis (IVT). We aimed to explore the contribution of stroke severity to the association between smoking and stroke prognosis after IVT.

Methods: We enrolled consecutive patients who received IVT within 4.5 hours from stroke onset. A logistic regression model was used to estimate the unadjusted and adjusted odds ratios (ORs) with their 95% confidence intervals (CIs) for poor functional outcome and mortality at 3 months.

Results: Among patients with moderate stroke, smokers experienced a lower risk of 3-month poor outcomes than non-smokers (33.0% vs. 44.4%, unadjusted OR: 0.616; 95% CI: 0.402-0.945). However, among those with severe stroke, smokers had a higher risk of 3-month poor outcomes than non-smokers (81.6% vs. 55.9%, unadjusted OR: 3.496; 95% CI: 1.207-10.127). After adjustment, the negative correlation between smoking and 3-month poor outcome following IVT lost statistical significance in patients with moderate stroke (OR: 0.677 [95% CI: 0.418-1.097]). However, smoking remained a risk factor for 3-month poor outcomes in patients with severe stroke (OR: 4.216 [95% CI: 1.236-14.385]). We also observed a significant interaction between smoking and stroke severity with regard to the risk of poor functional outcomes (p=0.023). However, no such interaction influenced mortality (p=0.901).

Conclusion: Stroke severity affects the association between smoking and 3-month clinical functional outcomes following IVT.