Ganesh, Aravind

Background: Endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT) have an unclear benefit in those with pre-stroke dementia or cognitive impairment, as these patients were often excluded from landmark stroke trials. We performed a systematic review and meta-analysis to assess the outcomes of IVT and EVT in these populations. Aims: Our systematic review, conforming to the Meta-Analysis of Observational Studies in Epidemiology guidelines, investigated studies on acute ischemic stroke patients with pre-stroke dementia or cognitive impairment treated with IVT or EVT. Primary outcome was favorable 90-day outcome (mRS 0–2). Secondary outcomes included 90-day mortality, symptomatic intracranial hemorrhage (SICH), and radiographic intracranial hemorrhage (ICH). Summary of review: Nine articles were identified, with five observational studies of IVT use in patients with (n = 1078) and without dementia (n = 2805) being selected for the meta-analysis. There were no significant differences in favorable outcome (adjusted OR: 0.61, 95% CI 0.24–1.59), mortality (unadjusted OR: 1.19, 95% CI 0.86–1.64), ICH (unadjusted OR: 1.32, 95% CI 0.79–2.19), and symptomatic ICH (unadjusted OR: 0.94, 95% CI 0.70–1.25) for patients undergoing IVT with pre-stroke dementia versus those without. One EVT study (n = 615 with dementia vs n = 9600 without) found no significant differences in outcomes apart from an increased odds of ICH for those with pre-existing dementia (adjusted OR: 1.57, 95% CI 1.03–2.40). A pooled analysis of three IVT studies showed no significant association of cognitive impairment (n = 93 vs n = 211 without) with all assessed outcomes, whereas a study of EVT found that pre-stroke cognitive impairment was associated with poor 90-day outcomes (mRS 3–6). Conclusion: These results suggest no substantial safety issues in the use of IVT or EVT for patients with pre-existing dementia or cognitive impairment compared to those without. However, the efficacy of these therapies in this demographic remains uncertain. Further rigorous studies that include a more nuanced outcome measurement approach are warranted. Registration: URL: https://www.crd.york.ac.uk/PROSPERO/ ; Unique identifier: CRD42021240499.

Symptomatic non-stenotic carotid plaques (SyNC) are an under-researched and under-recognized source of stroke. Various imaging markers of non-stenotic carotid plaques that are associated with stroke risk have been identified, but these causal relationships need to be confirmed in additional prospective studies. Currently, there exists neither a standardized SyNC definition nor a dedicated set of imaging protocols, although researchers have started to address these shortcomings. Moreover, many neuroradiologists are still unaware of the condition, and hence do not comment on high-risk plaque features other than stenosis in their reports. Regarding SyNC treatment, scant data exist as to whether and to what extent medical, interventional and surgical treatments could influence the course of the disease; the relative lack of data on the ‘natural’ history of untreated SyNC makes treatment comparisons difficult. In our opinion, endovascular SyNC treatment represents the most promising treatment option for SyNC, since it allows for targeted elimination of the embolic source, with few systemic side effects and without the need for general anesthesia. However, currently available carotid devices are designed to treat stenotic lesions, and thus are not optimally designed for SyNC. Developing a device specifically tailored to SyNC could be an important step towards establishing endovascular SyNC treatment in clinical practice. In this review, we provide an overview of the current state of evidence with regard to epidemiological, clinical and imaging features of SyNC, propose a SyNC definition based on imaging and clinical features, and outline a possible pathway towards evidence-based SyNC therapies, with a special focus on endovascular SyNC treatment.