Are We Overlooking Stroke Chameleons? A Retrospective Study on the Delayed Recognition of Stroke Patients

Patient factors associated with treatment time for stroke before and after the onset of COVID-19

OBJECTIVES

Prior to our study, little was known about factors related to time-to-treatment for stroke pre- and post-COVID-19.

DESIGN

This was a retrospective cohort study to evaluate factors associated with delayed door-to-needle time among patients with acute ischemic stroke over two time-periods.

RESULTS

Final sample consisted of 932 charts with mean age of 68.1(±15.6). Significant factors associated with shorter door-to-needle time included ≤ four hours since symptom onset and stroke occurring during post-Covid-19 time-period. Those on anti-coagulants had 72 % higher odds of longer door-to-needle time. As patients got older and stroke symptoms were more severe, less time was spent in door-to-imaging.

CONCLUSION

Results highlight the importance of early recognition of stroke symptoms and rapid transport to the hospital. Faster response times in post-Covid-19 time-period may be attributable to systematic processes put in place to address pandemic-related challenges. Outcomes may depend on research to identify gaps in stroke treatment.

Three Days Delayed Recanalization Improved Neurological Function in pMCAO Rats by Increasing M2 Microglia-Possible Involvement of the IL-4R/STAT6/PPARγ Pathway

Current approved therapies for acute ischemic stroke have a restricted therapeutic time window. Delayed recanalization, which has been utilized clinically in patients who have missed the time window for administration, may be a promising alternative for stroke patients. However, the underlying molecular mechanisms remain undiscovered. Herein, we hypothesized that delayed recanalization would increase M2 microglial polarization through the IL-4R (interleukin-4 receptor)/STAT6 (signal transducer and activators of transcription 6)/PPARγ (peroxisome proliferator-activated receptor γ) pathway, subsequently promoting stroke recovery in rats. The permanent middle cerebral artery occlusion (pMCAO) model was induced via intravascular filament insertion. Recanalization was induced by withdrawing the filament at 3 days after MCAO (rMCAO). Interleukin (IL)-4 was administered intranasally at 3 days after pMCAO. AS1517499, a specific STAT6 inhibitor, was administered intranasally at 3 days after MCAO induction. Immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), western blot analysis, volumetric measurements of brain infarct, and neurological behavior tests were conducted. Delayed recanalization at 3 days after MCAO increased the polarization of M2 microglia, decreased inflammation, and improved neurological behavior. IL-4 treatment administered on the 3rd day after pMCAO increased M2 microglial polarization, improved neurological behavior, and reduced infarction volume of pMCAO rats. The inhibition of STAT6 decreased the level of p-STAT6 and PPARγ in rats treated with delayed recanalization. Delayed recanalization improved neurological function by increasing microglial M2 polarization, possibly involved with the IL-4R/STAT6/PPARγ pathway after MCAO in rats.

Recurrence of ischaemic stroke using epidemiology and neuroimaging: A retrospective study in Gansu Province

Objectives

This retrospective study aimed to investigate the clinical and imaging recurrence of ischaemic stroke (IS), and to evaluate the risk factors for recurrence. A combined clinical and imaging diagnostic model is important for stroke prevention and management.

Methods and materials

In accordance with the inclusion and exclusion criteria, we retrospectively analysed consecutively hospitalised patients with acute IS at the Affiliated Hospital of Gansu University of Chinese Medicine. Based on the epidemiological and imaging results, stroke episodes were divided into four categories: clinical first episode (CFE), clinical recurrence (CR), imaging first episode (IFE), and imaging recurrence (IR). Based on the above categories and clinical practice, a joint diagnostic system for IS was established for the first time, including the following five types: IFE, IR, CFE and IFE, CFE and IR, and CR and IR. A binomial logistic regression analysis was conducted to determine the factors which contributed to CR and IR.

Results

In total, 280 patients were assessed. The CR rate was 22.9% (64/280) and the IR rate was 62.9% (176/280). The only predictor of CR was hypertension (P = 0.019, odds ratio [OR] = 3.041, 95% confidence interval [95%CI] = 1.200-7.704). The factors of hypertension (P < 0.001, OR = 3.551, 95%CI = 1.781-7.080) and age (P = 0.031, OR = 1.031, 95%CI = 1.003-1.060) were predictors of IR.

Conclusion

The IR rates for IS were three times higher than the CR rates. The key to preventing IR and CR in IS was the management of blood pressure. Neuroimaging examinations were important for the early detection of IFE and IR in elderly patients with hypertension. A combined clinical imaging diagnostic model was developed for the first time.

Evolution of the stroke paradigm: A review of delayed recanalization

While the time window for reperfusion after ischemic stroke continues to increase, many patients are not candidates for reperfusion under current guidelines that allow for reperfusion within 24 h after last known well time; however, many case studies report favorable outcomes beyond 24 h after symptom onset for both spontaneous and medically induced recanalization. Furthermore, modern imaging allows for identification of penumbra at extended time points, and reperfusion risk factors and complications are becoming better understood. Taken together, continued urgency exists to better understand the pathophysiologic mechanisms and ideal setting of delayed recanalization beyond 24 h after onset of ischemia.

Stroke chameleons: acute central pain mimicking acute coronary syndrome

BACKGROUND AND PURPOSE

'Stroke chameleons' refer to a group of syndromes that initially are not diagnosed as cerebrovascular events but are then found to represent stroke. The objective of this study was to report on acute ischaemic stroke (AIS) patients with chest or epigastric pain of central origin, clinically resembling an acute coronary syndrome (ACS).

METHODS

A prospective list was kept of AIS patients admitted to our institution between 2002 and 2014 with stroke symptoms appearing as an ACS on first clinical evaluation. For each identified patient, clinical and radiological features, delay to correct diagnosis, stroke etiology and 3-month functional outcome were reviewed. Data were mainly extracted from the Acute Stroke Registry and Analysis of Lausanne (ASTRAL).

RESULTS

Five AIS patients presenting mainly with chest or epigastric pain leading to a wrong diagnosis of ACS were identified. Cardiac evaluation showed minor electrocardiogram changes in two patients and isolated troponin elevation in one, subsequently shown to be of non-coronary origin. The correct diagnosis of AIS was made only between 1 h and 72 h after hospital arrival. Four patients presented a vertebrobasilar stroke. None of the patients received acute stroke revascularization therapy despite two of them being in the time window for such treatment.

CONCLUSION

Acute ischaemic stroke presentation can infrequently resemble an ACS. In cases of negative cardiac work-up, a central origin of chest pain should be considered, especially in the presence of subtle other neurological symptoms or signs. Appropriate diagnosis of stroke could avoid treatment delays and improve outcomes.

Molecular Magnetic Resonance Imaging of Endothelial Activation in the Central Nervous System

Endothelial cells of the central nervous system over-express surface proteins during neurological disorders, either as a cause, or a consequence, of the disease. Since the cerebral vasculature is easily accessible by large contrast-carrying particles, it constitutes a target of choice for molecular magnetic resonance imaging (MRI). In this review, we highlight the most recent advances in molecular MRI of brain endothelial activation and focus on the development of micro-sized particles of iron oxide (MPIO) targeting adhesion molecules including intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), P-Selectin and E-Selectin. We also discuss the perspectives and challenges for the clinical application of this technology in neurovascular disorders (ischemic stroke, intracranial hemorrhage, subarachnoid hemorrhage, diabetes mellitus), neuroinflammatory disorders (multiple sclerosis, brain infectious diseases, sepsis), neurodegenerative disorders (Alzheimer's disease, vascular dementia, aging) and brain cancers (primitive neoplasms, metastasis).