Cerebrovascular Diseases Extra最新文献

Background: Stroke related to infections represents a less common but significant cause, particularly in low- and middle-income countries. This review examines the pathophysiology of stroke from infections, involving both direct and indirect mechanisms.

Summary: Bacterial infections such as tuberculous meningitis and infective endocarditis can directly cause strokes through local inflammation, arteritis, and septic embolism. Viral infections like Varicella zoster virus and HIV increase stroke risk through chronic immune activation, vasculopathy, and endothelial dysfunction. Parasitic infections, particularly malaria and neurocysticercosis, can cause strokes via vascular occlusion and inflammatory responses. Fungal infections like aspergillosis and mucormycosis can lead to strokes through vasculitis and direct invasion of the CNS.

Key messages: Understanding the mechanisms by which various infectious agents contribute to stroke pathogenesis is essential for developing targeted therapeutic strategies and improving patient outcomes. Further research is needed to establish effective prevention and treatment for infection-related strokes, especially in low- and middle-income countries.

Introduction: Intracranial artery stenosis (ICAS) is a significant contributor to cortical infarcts, and studies have also shown associations between ICAS and structural brain changes, such as lacunes, white matter hyperintensities (WMHs), and brain atrophy. We aimed to assess the associations between ICAS and cortical infarcts, lacunes, WMHs, and brain parenchymal fraction (BPF) in a general population.

Methods: We included 1,842 participants (981 women and 861 men) aged 40-84 years who participated in a cross-sectional population-based study. Three-dimensional time-of-flight magnetic resonance angiography was used for the assessment of ICAS, while 3D T2-fluid-attenuated inversion recovery sequences, 3D T1-weighted sequences, and susceptibility-weighted images were used for evaluation of brain structure. ICAS was defined as a ≥50% focal narrowing of the intracranial arterial flow diameter. WMHs were assessed by the Fazekas score and automated volumetric measurements. BPF was used as a proxy for brain atrophy.

Results: The 111 participants (6.0%) with ICAS had significantly more cortical infarcts (23.4% vs. 5.5%, p < 0.001) and lacunes (27.0% vs. 7.7%, p < 0.001) compared to participants without ICAS (1,731). Multivariable-adjusted analysis showed an independent association between ICAS and cortical infarcts (OR: 2.23, 95% CI: 1.27 to 3.90, p = 0.005) and lacunes (OR 2.05, 95% CI: 1.24 to 3.41, p = 0.005), mainly driven by lacunes in the posterior circulation (OR: 4.76, 95% CI: 1.75 to 12.97, p = 0.002). ICAS was independently associated with moderate-to-severe periventricular Fazekas score (OR 2.04, 95% CI: 1.26 to 3.28) and BPF (β-coefficient -0.0131, 95% CI: -0.0232 to -0.0030). There was no significant association between ICAS and deep moderate-to-severe Fazekas score or WMH volumes.

Conclusion: ICAS was associated with both cortical infarcts in the anterior and posterior circulation and with lacunes in the posterior circulation. The results also indicate a relationship between ICAS and periventricular WMHs and brain atrophy.

Introduction: Timely thrombolytic therapy improves outcomes in acute ischemic stroke. Manual chart review to screen for thrombolysis contraindications may be time-consuming and prone to errors. We developed and tested a large language model (LLM)-based tool to identify thrombolysis contraindications from clinical notes using synthetic data in a proof-of-concept study.

Methods: We generated 150 synthetic clinical notes containing randomly assigned thrombolysis contraindications using LLMs. We then used Llama 3.1 405B with a custom prompt to generate a list of thrombolysis contraindications from each note. Performance was evaluated using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and F1 score.

Results: A total of 150 synthetic notes were generated using five different models: ChatGPT-4o, Llama 3.1 405B, Llama 3.1 70B, ChatGPT-4o mini, and Gemini 1.5 Flash. On average, each note contained 241.6 words (SD 110.7; range 80-549) and included 1.5 contraindications (SD 1.1; range 0-5). Our tool achieved a sensitivity of 90.9% (95% CI: 86.3%-94.3%), specificity of 99.2% (95% CI: 98.8%-99.5%), PPV of 87.7% (95% CI: 82.7%-91.7%), NPV of 99.4% (95% CI: 99.1%-99.6%), accuracy of 98.7% (95% CI: 98.2%-99.0%), and an F1 score of 0.892. Among the false positives, 24 (86%) were due to the inclusion of irrelevant contraindications, and 4 (14%) resulted from repetitive information. No hallucinations were observed.

Conclusion: Our LLM-based tool may identify stroke thrombolysis contraindications from synthetic clinical notes with high sensitivity and PPV. Future studies will validate its performance using real EMR data and integrate it into acute stroke workflows to facilitate faster and safer thrombolysis decision-making.

Introduction: In Vietnam, the incidence of transient ischemic attack (TIA) or ischemic stroke has increased in recent years due to lifestyle changes. Carotid stenosis is a common cause of TIA/ischemic stroke. This study aimed to determine the prevalence and identify risk factors for ipsilateral internal carotid artery (ICA) stenosis in patients with TIA or ischemic stroke.

Methods: We recruited consecutive patients admitted to Bach Mai hospital from June/2021 to June/2022 with the diagnosis of TIA/ischemic stroke. The primary outcome was the presence of significant ipsilateral carotid stenosis (≥50%) by using carotid imaging modalities (duplex ultrasonography, computed tomography angiography, or magnetic resonance angiography). Univariable and multivariable logistic regression analyses were performed to identify risk factors associated with 50-99% ICA stenosis.

Results: In total, 1,191 consecutive patients with TIA/ischemic stroke were included. Of these, 62 (5.2%, 95% confidence interval [CI]: 4.0-6.6) had 50-99% ipsilateral ICA stenosis. Patients with significant ICA stenosis were more likely to have advanced age, male sex, and prior stroke. In multivariable logistic regression, advanced age (OR 1.49 per 10-year increment; 95% CI: 1.17-1.90, p = 0.001), male sex (OR 4.94; 95% CI: 2.15-11.38, p < 0.001), and prior stroke (OR 2.01; 95% CI: 1.12-3.62, p = 0.02) were risk factors for ICA stenosis.

Conclusion: The observed prevalence of extracranial ICA stenosis in TIA/ischemic stroke patients in Vietnam appears to be lower compared to Western nations, yet it is relatively comparable to that of other Asian countries. Male sex, prior stroke, and advanced age constitute significant risk factors for symptomatic ICA stenosis.

Introduction: Patients who have undergone reperfusion treatments, like all ischemic stroke patients, are at risk of recurrent ischemic strokes in the first 90 days. Current guidelines recommend single antiplatelet therapy for secondary prevention at variable time points after the procedure. This study assessed the practices and perspectives of healthcare professionals on the use of dual antiplatelet therapy in patients with non-cardioembolic ischemic stroke who have undergone reperfusion therapy.

Methods: We conducted a multinational cross-sectional web-based survey using Qualtrics involving neurologists and non-neurologist stroke physicians (including neurosurgeons, interventional neuroradiologists, and internal medicine physicians). Participants were asked about their current practices and presented with six structured case scenarios to determine their treatment preferences. In the case scenarios, we assessed their willingness to randomize to a clinical trial comparing single versus dual antiplatelets. Multinomial logistic regression analysis was performed to assess the relationship between demographic characteristics and willingness to randomize.

Results: A total of 278 clinicians from 26 countries participated in the survey. The most common continent of practice was Asia (155/278; 55.9%). The most common area of practice was neurology (220/278; 79.1%), with most participants having 5-15 years of experience (115/278; 41.5%) and working in comprehensive stroke centers (205/278; 73.9%). Antiplatelet Choice: For a small infarct post-intravenous thrombolysis and endovascular thrombectomy (EVT), 194/278 (69.8%) preferred aspirin, and 49/278 (17.6%) chose a dual antiplatelet strategy with aspirin and clopidogrel. Loading of Antiplatelet: A total of 121/278 (43.5%) indicated they would not administer a loading dose in cases even with small final infarctions. Timing of Antiplatelet Initiation: Preferences varied; 61/278 (21.7%) considered early initiation immediately post-EVT, and 103/278 (37.2%) considered 24 h post-EVT. Willingness to Randomize: A total of 16/278 (77.7%) were willing or would consider randomizing in a clinical trial with dual antiplatelet. On regression analyses, the willingness to randomize was influenced by years of practice and the local volume of reperfusion therapy.

Conclusion: Antiplatelet management for secondary stroke prevention in patients with non-cardioembolic ischemic stroke following reperfusion therapy is variable. However, more than three-fourths of participants were willing to consider randomization to a clinical trial exploring the prevention of recurrent stroke after reperfusion therapy.

Introduction: Intracranial large artery atherosclerosis (ICAS) is a common cause of stroke in Asia. Prior epidemiological publications on ICAS have largely been single-country reports. This collaborative study involving several Asian countries aims to investigate the characteristics and outcomes of patients with stroke attributable to ICAS.

Methods: This is an international, multicenter, observational, prospective cohort study of patients admitted with acute ischemic stroke secondary to ICAS to stroke centers in six Asian countries. Stroke due to ICAS was diagnosed when there was a ≥50% intracranial large artery stenosis ipslateral to a non-lacunar infarct, without significant ipsilateral extracranial stenosis, cardiac cause or other mechanism found for the stroke. Data were collected on patient demographics, vascular risk factors, stroke location, and severity. Outcomes of interest were stroke recurrence and mortality at 12-month follow-up.

Results: A total of 356 patients were recruited. Mean age was 62.7 ± 13.8 years, and 39.9% were females. Mean NIHSS on admission was 9 ± 8, with majority of patients having mild (39.3%) or moderate (37.9%) strokes. Stroke recurrence was 6.7% (95% CI: 4.4-9.9%) while mortality rate was 13.2% (95% CI: 9.9-17.2%) within 1 year. The risk of stroke recurrence was associated with increasing age (odds ratio [OR]: 1.04, 95% CI: 1-1.06, p = 0.05) and hypertension (OR: 3.23, 95% CI: 1.09-9.61, p = 0.035). Mortality was associated with age (OR: 1.05, 95% CI: 1.01-1.08, p = 0.006) and NIHSS (OR: 1.12, 95% CI: 1.07-1.17, p < 0.001).

Conclusions: This multicenter Asian study demonstrates a high risk of stroke recurrence and mortality among patients with acute stroke due to ICAS. They are associated with age (both), as well as hypertension (for recurrence) and NIHSS (for mortality). Better treatment modalities are needed to reduce the frequency of adverse outcomes in symptomatic ICAS.

Introduction: There are limited data on the characteristics of stroke in young adults in East Asia including Japan. We aimed to clarify the clinical characteristics of ischemic stroke in Japanese young adults.

Methods: We prospectively enrolled ischemic stroke patients aged 18-50 years old who were admitted to 5 high-volume stroke centers within 14 days after onset between February 2018 and January 2023. We collected clinical and imaging data based on the study protocol and analyzed them for conventional and specific stroke risk factors, stroke etiology, and clinical outcome.

Results: We enrolled 275 subjects (median age, 46 years; men, 71%; full-time workers, 75%; median NIHSS score at admission, 2 points). The major risk factors were dyslipidemia (59%), hypertension (49%), and smoking (32%). Hyperhomocysteinemia, migraine, and antiphospholipid syndrome were found in 21%, 11%, and 5%, respectively. The RNF213 p.R4810K variant was identified in 4.5%. The most common stroke etiologies were small vessel occlusion (26%) and arterial dissection (25%; intracranial in 20% and extracranial in 5%). The stroke recurrence rate was 5% at 3 months. Modified Rankin scale 0-1 at 3 months was observed in 76%, whereas 61% were able to return to their previous full-time work and 31% exhibited symptoms of depression.

Conclusions: The leading stroke etiologies in young adults in Japan were small vessel occlusion and intracranial arterial dissection, which differ from those observed in Western countries. Most young stroke patients had a favorable outcome, but some of them encountered problems relating to employment or mental health after their stroke.

Introduction: The recently proposed cerebral small vessel disease (CSVD) score system may help capture the overall burden of CSVD. This study aimed to investigate the associations between carotid artery ultrasound features and the burden score and cognitive performance of CSVD patients.

Methods: This is a cross-sectional analysis of an ongoing prospective study. From May 2019 to October 2023, 287 patients with at least one neuroimaging marker of CSVD were recruited and underwent carotid ultrasound examination, brain magnetic resonance imaging (MRI) scans, and neuropsychological assessment. Carotid artery properties, including carotid plaque, intima-media thickness (IMT), β stiffness index (β-index), Peterson's elastic modulus (PEM), and pulse wave velocity-β (PWV-β), were calculated. The CSVD score was graded according to MRI evaluation. Participants were classified as having cognitive impairment (CI) or normal cognitive function (NCF) according to Montreal Cognitive Assessment (MoCA) scale.

Results: A total of 209 eligible patients were included in the final analysis. A significant difference was revealed regarding the CSVD score between CI and NCF participants (p < 0.001). After adjusted for covariates, increased IMT (OR = 1.11, 95% CI: 1.04-1.37, p = 0.030) and PWV-β (OR = 1.24, 95% CI: 1.09-1.51, p = 0.006) were both associated with the presence of CI. IMT and PWV-β were also associated with worse performance on attention and processing speed (IMT: β = -0.13, p = 0.011; PWV-β: β = -0.21, p = 0.011), and executive function (IMT: β = -0.20, p = 0.024; PWV-β: β = -0.33, p = 0.008). Additionally, PEM was negatively associated with executive function (β = -0.20, p = 0.009). Furthermore, binary logistic regression indicated that IMT (OR = 1.45, 95% CI: 1.18-2.01, p = 0.006), β-index (OR = 1.30, 95% CI: 1.10-1.64, p = 0.008) and PWV-β (OR = 1.23, 95% CI: 1.01-1.89, p = 0.047) were independently related to a moderate to severe CSVD burden score.

Conclusions: Carotid artery atherosclerosis and stiffness are associated with the burden score and cognitive performance of CSVD patients. Noninvasive ultrasound parameters of the carotid artery are capable of discriminating high-risk individuals with CSVD.

Introduction: This study investigates the impact of trimethylamine oxide (TMAO) on recurrent cerebral infarction in minor ischaemic stroke (MIS).

Methods: A rat model was used, with dietary choline levels adjusted to vary TMAO levels. TMAO was quantified via liquid chromatography-mass spectrometry, and histological changes in brain and aortic tissues were analysed using HE staining.

Results: Data analysis showed that TMAO levels and neurological deficit scores increased progressively across groups, correlating positively with the severity of cerebral and arterial pathology. High choline diets significantly elevated TMAO levels, aggravating infarction and atherosclerosis, while low choline diets reduced these effects.

Conclusions: TMAO demonstrated medium-high diagnostic value for neurological deficits, infarction size, and arterial damage. These findings suggest that elevated TMAO levels are linked to worse outcomes in MIS, highlighting the potential of TMAO as a biomarker for diagnosis and prevention of recurrent cerebral infarction.

Introduction: Recent trials have demonstrated the remarkable benefit of endovascular treatment (EVT) up to 24 h in patients with large vessel occlusion (LVO) and target mismatch profiles; however, benefits of late-window EVT in Vietnamese population remain poorly understood. This study aims to evaluate the real-world outcomes of EVT in acute ischemic stroke (AIS) patients selected using perfusion imaging within the 6-24-h window.

Methods: This is a prospective study of consecutive patients with anterior circulation LVO stroke who underwent EVT within 6-24 h after last known well between August 2022 and March 2024. Patients were selected based on the DAWN/DEFUSE-3 criteria (Perfusion-RAPID, iSchemaView). The primary outcome was the proportion of patients with functional independence at 90 days (modified Rankin Scale score of 0-2). The secondary outcomes were successful reperfusion defined by thrombolysis in cerebral infarction (TICI) ≥2b on the final procedure and subgroup analysis between good (hypoperfusion intensity ratio [HIR] <0.4) and poor collaterals (HIR ≥0.4) groups. Safety outcomes were mortality rate and symptomatic intracranial hemorrhage (sICH).

Results: Of 122 enrolled patients, 68% met inclusion criteria of DEFUSE-3 trial, 61% met DAWN trial criteria. Mean age was 66 years, median baseline NIHSS was 13, median time from stroke onset to hospital arrival was 12.55 h (9.50-16.48), and median infarct volume was 11.5 mL. The rate of functional independence at 90 days was 45.9%. Successful reperfusion (TICI score of ≥2b) was achieved by 83.6% of cases. The 90-day mortality rate was 10.7%; sICH was reported in 8 patients (6.6%). Patients with good collaterals had better functional outcome.

Conclusions: This real-world observational study suggests that late-window EVT may be safe and effective in eligible Vietnamese patients selected based on perfusion imaging, thus supporting its practical use in this patient population. HIR is a robust indicator of collateral status and could made it a valuable addition to stroke imaging workup in clinical setting.