Stroke最新文献

Background: Vascular territory mapping (VTM) software estimates which intracerebral vessel provides predominant arterial flow to a brain voxel. The presence of antegrade flow in the setting of acute middle cerebral artery (MCA) occlusion is associated with improved outcomes. We identify whether VTM software is a determinant of antegrade flow in patients with proximal MCA occlusion.

Methods: Consecutive patients with the first branch of MCA (M1) occlusion were analyzed from the International Stroke Perfusion Imaging Registry with their computed tomography perfusion reprocessed through VTM software. Authors reviewed dynamic 4-dimensional computed tomography angiography for the presence of an acute M1 thrombus and also for the presence of residual antegrade flow. The VTM software assigned regions of the brain to an estimated feeding vessel (anterior cerebral artery, MCA, and posterior cerebral artery). A binomial logistic regression was performed to determine the effects of VTM, ischemic core (cerebral blood flow <30), and perfusion lesion (delay time >3) on the likelihood that patients had the presence of any antegrade flow in the MCA territory. A secondary analysis was performed to assess the relationship between imaging variables and 3-month modified Rankin Scale outcomes.

Results: The final data set included 130 patients with M1 occlusion. The median age of participants was 74 years (interquartile range, 62-81) with an onset-to-scan time of 2.1 hours (interquartile range, 1.4-3.8) and a National Institutes of Health Stroke Scale score of 15 (interquartile range, 12-20). Eighteen patients were identified with antegrade flow on 4-dimensional digital subtraction angiography. Patients with antegrade flow had significantly larger VTM volume normal side MCA, 101 (72-180) mL, compared with those with complete occlusion, 41 (21-71) mL. VTM volume normal side MCA volume significantly predicted antegrade flow and outcome, and 1 mL VTM volume normal side MCA volume increased odds of antegrade flow by 1.024 (95% CI, 1.013-1.036). Ischemic core and the perfusion lesion volumes did not predict antegrade flow.

Conclusions: VTM software was more effective than traditional perfusion parameters in the detection of antegrade flow. The results demonstrate a potential clinical utility for VTM; however, larger cohorts will be required to detect whether VTM can predict clinical outcome after reperfusion treatment.

Background: Stroke secondary to intracranial atherosclerotic disease (ICAD) is associated with high recurrence risk despite currently available secondary prevention strategies. In patients with systemic atherosclerosis, a significant reduction of stroke risk with no increase in intracranial or fatal hemorrhage was seen when rivaroxaban 2.5 mg twice daily was added to aspirin. However, there are no trials in ICAD using this combination. To facilitate the design of future ICAD trials, the CATIS-ICAD study (Combination Antithrombotic Treatment for Prevention of Recurrent Ischemic Stroke in Intracranial Atherosclerotic Disease) assessed (1) the feasibility of recruitment, (2) the safety of low-dose rivaroxaban plus aspirin compared with standard-of-care antiplatelet therapy, and (3) trends toward efficacy.

Methods: This was a prospective, randomized, open-label, blinded end point pilot trial conducted in 10 Canadian centers. Eligible participants aged ≥40 years, with acute ischemic stroke or high-risk transient ischemic attack, were randomly assigned in a 1:1 ratio to receive low-dose rivaroxaban plus aspirin or aspirin alone within 7 to 100 days of their index event. The primary safety outcome was hemorrhagic stroke. The main efficacy end point was the composite of ischemic stroke or covert brain infarct on magnetic resonance imaging at the end of the study.

Results: A total of 101 participants were randomized. Average enrollment was 10 participants/site per year. Average follow-up was 20 months. Median time from index stroke to randomization was 67 days. The median age of participants was 67 years (±10.94), and 29% of participants were women. There was no hemorrhagic stroke in either arm. The composite efficacy outcome was less frequent in the combination arm (15.7%) compared with the aspirin arm (24.0%), with a hazard ratio of 0.78 ([95% CI, 0.32-1.93]; P=0.59) favoring the intervention.

Conclusions: A multicenter randomized trial comparing the combination of low-dose rivaroxaban and aspirin in patients with recent ischemic stroke or transient ischemic attack due to ICAD is feasible and appears safe without an increased risk of hemorrhagic stroke. A numerical trend toward efficacy for the composite primary end point of symptomatic ischemic stroke and covert infarcts was observed. These findings will inform the design of a phase III trial.

Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04142125.

Background: How cerebral microbleeds (CMBs) are formed, and how they cause tissue damage is not fully understood, but it has been suggested they are associated with inflammation, and they could also be related to increased blood-brain barrier (BBB) leakage. We investigated the relationship of CMBs with inflammation and BBB leakage in cerebral small vessel disease, and in particular, whether these 2 processes were increased in the vicinity of CMBs.

Methods: In 54 patients with sporadic cerebral small vessel disease presenting with lacunar stroke, we simultaneously assessed microglial activation using the positron emission tomography ligand [11C]PK11195 and BBB leakage using dynamic contrast enhanced magnetic resonance imaging, on a positron emission tomography-magnetic resonance imaging system. To assess local inflammation and BBB leakage, 3 one-voxel concentric shells were generated around each CMB on susceptibility-weighted imaging and resampled to positron emission tomography and T1 mapping images, respectively. In these 3 shells, we calculated the mean of PK11195 nondisplaceable binding potential (BPND) as a marker of microglial activation, as well as the mean influx rate as a marker of BBB leakage. In addition, 93 blood biomarkers related to cardiovascular disease, inflammation, and endothelial activation were measured to quantify systemic inflammation.

Results: No significant associations were found between the number of CMBs and the measures for microglial activation (β=2.6×10^-5, P=0.050) and BBB leakage (β=-0.0001, P=0.400) in the white matter. There was no difference in measures of microglial activation (P=0.403) or BBB leakage (P=0.423) across the 3 shells surrounding the CMBs. Furthermore, after correcting for multiple comparisons, no associations were observed between systemic inflammation biomarkers and the number of CMBs.

Conclusions: We found no evidence that CMBs are associated with either microglial activation assessed by [11]CPK11195 positron emission tomography or BBB leakage assessed by dynamic contrast enhanced magnetic resonance imaging, either globally or locally, in sporadic cerebral small vessel disease. There was also no association with markers of systemic inflammation.

Considerable variation exists in the delivery of acute stroke care and stroke outcomes across settings and population groups. This is attributable in part to variation in resources among emergency departments in the United States, most notably in rural regions. Structural constraints of the US health care system, including the geographic distribution of where patients live relative to the location of hospitals and certified stroke centers, will continue to mean that many patients with stroke initially present to community emergency departments that have fewer stroke-related resources. These sites also tend to serve populations in rural areas who experience disparities in care and outcomes. Reducing health disparities related to stroke for populations in rural areas requires investment in these more remote community settings as the anchor of the stroke chain of survival for their respective communities. This scientific statement performs a critical appraisal examining challenges in rural stroke care related to access and variation in stroke-related capabilities for the acute phase of care to inform strategies and propose solutions. The scientific statement considers the value of expansion of Acute Stroke Ready Hospital and Primary Stroke Center certification in rural areas, the role of telehealth and improved transfer processes, as well as increased engagement and mentorship from larger, comprehensive centers to the rural hospitals to which they are connected. Multistakeholder collaboration and policy interventions need to be directed to enhance public awareness, impart staff training, grow infrastructure, enhance access to clinical expertise, streamline data management, and implement quality assessment and improvement programs.

In recent years, stroke incidence in older adults has declined strikingly, but stroke in younger women has become more common. Abnormalities of menstruation, the shedding of the uterine lining at the beginning of each menstrual cycle, may offer clues about stroke risk in young and midlife women. Endometrial and structural uterine abnormalities are associated with anemia and may be associated with hypercoagulability, possibly increasing stroke risk. Patient factors that influence both menstruation and stroke risk include coagulopathies, polycystic ovarian syndrome, endometriosis, migraine, and other systemic disorders, in addition to menopause. Environmental and iatrogenic factors that influence both menstruation and stroke risk include hormonal contraceptives, nicotine, xenoestrogens, phytoestrogens, oophorectomy, and hysterectomy. Importantly, secondary stroke prevention can affect menstruation. Our current review presents literature supporting the idea that abnormal menstruation may indicate elevated stroke risk in premenopausal women.