Left Ventricular Diastolic Dysfunction Is Associated with Poor Functional Outcomes after Endovascular Thrombectomy.

INTRODUCTION: With the advent of endovascular thrombectomy (ET), patients with acute ischaemic strokes (AIS) with large vessel occlusion (LVO) have seen vast improvements in treatment outcomes. Left ventricular diastolic dysfunction (LVDD) has been shown to herald poorer prognosis in conditions such as myocardial infarction. However, whether LVDD is related to functional recovery and outcomes in ischaemic stroke remains unclear. We studied LVDD for possible relation with clinical outcomes in patients with LVO AIS who underwent ET. METHODS: We studied a retrospective cohort of 261 LVO AIS patients who had undergone ET at a single comprehensive stroke centre and correlated LVDD to short-term mortality (in-hospital death) as well as good functional recovery defined as modified Rankin Scale of 0-2 at 3 months. RESULTS: The study population had a mean age of 65-years-old and were predominantly male (54.8%). All of the patients underwent ET with 206 (78.9%) achieving successful reperfusion. Despite this, 25 (9.6%) patients demised during the hospital admission and 149 (57.1%) did not have good function recovery at 3 months. LVDD was present in 82 (31.4%) patients and this finding indicated poorer outcomes in terms of functional recovery at 3 months (OR 2.18, 95% CI 1.04-4.54, p = 0.038) but was not associated with increased in-hospital mortality (OR 2.18, 95% CI 0.60-7.99, p = 0.240) after adjusting for various confounders. CONCLUSION: In addition to conventional echocardiographic indices such as left ventricular ejection fraction, LVDD may portend poorer outcomes after ET, and this relationship should be investigated further.

Acute Myocardial Infarction and Risk of Cognitive Impairment and Dementia: A Review.

Cognitive impairment (CI) shares common cardiovascular risk factors with acute myocardial infarction (AMI), and is increasingly prevalent in our ageing population. Whilst AMI is associated with increased rates of CI, CI remains underreported and infrequently identified in patients with AMI. In this review, we discuss the evidence surrounding AMI and its links to dementia and CI, including pathophysiology, risk factors, management and interventions. Vascular dysregulation plays a major role in CI, with atherosclerosis, platelet activation, microinfarcts and perivascular inflammation resulting in neurovascular unit dysfunction, disordered homeostasis and a dysfunctional neurohormonal response. This subsequently affects perfusion pressure, resulting in enlarged periventricular spaces and hippocampal sclerosis. The increased platelet activation seen in coronary artery disease (CAD) can also result in inflammation and amyloid-ß protein deposition which is associated with Alzheimer's Dementia. Post-AMI, reduced blood pressure and reduced left ventricular ejection fraction can cause chronic cerebral hypoperfusion, cerebral infarction and failure of normal circulatory autoregulatory mechanisms. Patients who undergo coronary revascularization (percutaneous coronary intervention or bypass surgery) are at increased risk for post-procedure cognitive impairment, though whether this is related to the intervention itself or underlying cardiovascular risk factors is debated. Mortality rates are higher in dementia patients with AMI, and post-AMI CI is more prevalent in the elderly and in patients with post-AMI heart failure. Medical management (antiplatelet, statin, renin-angiotensin system inhibitors, cardiac rehabilitation) can reduce the risk of post-AMI CI; however, beta-blockers may be associated with functional decline in patients with existing CI. The early identification of those with dementia or CI who present with AMI is important, as subsequent tailoring of management strategies can potentially improve outcomes as well as guide prognosis.

Left Ventricular Ejection Fraction Association with Acute Ischemic Stroke Outcomes in Patients Undergoing Thrombolysis.

(1) Background: Little is known about how left ventricular systolic dysfunction (LVSD) affects functional and clinical outcomes in acute ischemic stroke (AIS) patients undergoing thrombolysis; (2) Methods: A retrospective observational study conducted between 2006 and 2018 included 937 consecutive AIS patients undergoing thrombolysis. LVSD was defined as left ventricular ejection fraction (LVEF) < 50%. Univariate and multivariate binary logistic regression analysis was performed for demographic characteristics. Ordinal shift regression was used for functional modified Rankin Scale (mRS) outcome at 3 months. Survival analysis of mortality, heart failure (HF) admission, myocardial infarction (MI) and stroke/transient ischemic attack (TIA) was evaluated with a Cox-proportional hazards model; (3) Results: LVSD patients in comparison with LVEF ≥ 50% patients accounted for 190 and 747 patients, respectively. LVSD patients had more comorbidities including diabetes mellitus (100 (52.6%) vs. 280 (37.5%), p < 0.001), atrial fibrillation (69 (36.3%) vs. 212 (28.4%), p = 0.033), ischemic heart disease (130 (68.4%) vs. 145 (19.4%), p < 0.001) and HF (150 (78.9%) vs. 46 (6.2%), p < 0.001). LVSD was associated with worse functional mRS outcomes at 3 months (adjusted OR 1.41, 95% CI 1.03-1.92, p = 0.030). Survival analysis identified LVSD to significantly predict all-cause mortality (adjusted HR [aHR] 3.38, 95% CI 1.74-6.54, p < 0.001), subsequent HF admission (aHR 4.23, 95% CI 2.17-8.26, p < 0.001) and MI (aHR 2.49, 95% CI 1.44-4.32, p = 0.001). LVSD did not predict recurrent stroke/TIA (aHR 1.15, 95% CI 0.77-1.72, p = 0.496); (4) Conclusions: LVSD in AIS patients undergoing thrombolysis was associated with increased all-cause mortality, subsequent HF admission, subsequent MI and poorer functional outcomes, highlighting a need to optimize LVEF.

Etiologies, mechanisms, and risk factors of ischemic stroke in a young Asian adult cohort.

OBJECTIVES: Risk factors and causes of acute ischemic stroke (AIS) are more diverse in young adults, and traditional stroke classifications may be inadequate. Precise characterisation of AIS is important for guiding management and prognostication. We describe stroke subtypes, risk factors and etiologies for AIS in a young Asian adult population. MATERIALS AND METHODS: Young AIS patients aged 18-50 years admitted to two comprehensive stroke centres from 2020-2022 were included. Stroke etiologies and risk factors were adjudicated using Trial of Org 10172 in Acute Stroke Treatment (TOAST) and International Pediatric Stroke Study (IPSS) risk factors. Potential embolic sources (PES) were identified in a subgroup with embolic stroke of undetermined source (ESUS). These were compared across sex, ethnicities and age groups (18-39 years versus 40-50 years). RESULTS: A total of 276 AIS patients were included, with mean age 43±5.7 years and 70.3% male. Median duration of follow-up was 5 months (IQR: 3-10). The most common TOAST subtypes were small-vessel disease (32.6%) and undetermined etiology (24.6%). IPSS risk factors were identified in 95% of all patients and 90% with undetermined etiology. IPSS risk factors included atherosclerosis (59.5%), cardiac disorders (18.7%), prothrombotic states (12.4%) and arteriopathy (7.7%). In this cohort, 20.3% had ESUS, of which 73.2% had at least one PES, which increased to 84.2% in those <40 years old. CONCLUSIONS: Young adults have diverse risk factors and causes of AIS. IPSS risk factors and ESUS-PES construct are comprehensive classification systems that may better reflect heterogeneous risk factors and etiologies in young stroke patients.

Association of Shunt Size and Long-Term Clinical Outcomes in Patients with Cryptogenic Ischemic Stroke and Patent Foramen Ovale on Medical Management.

INTRODUCTION: Patent foramen ovale (PFO) is a potential source of cardiac embolism in cryptogenic ischemic stroke, but it may also be incidental. Right-to-left shunt (RLS) size may predict PFO-related stroke, but results have been controversial. In this cohort study of medically-managed PFO patients with cryptogenic stroke, we aimed to investigate the association of shunt size with recurrent stroke, mortality, newly detected atrial fibrillation (AF), and to identify predictors of recurrent stroke. METHODS: Patients with cryptogenic stroke who screened positive for a RLS using a transcranial Doppler bubble study were included. Patients who underwent PFO closure were excluded. Subjects were divided into two groups: small (Spencer Grade 1, 2, or 3; n = 135) and large (Spencer Grade 4 or 5; n = 99) shunts. The primary outcome was risk of recurrent stroke, and the secondary outcomes were all-cause mortality and newly detected AF. RESULTS: The study cohort included 234 cryptogenic stroke patients with medically-managed PFO. The mean age was 50.5 years, and 31.2% were female. The median period of follow-up was 348 (IQR 147-1096) days. The rate of recurrent ischemic stroke was higher in patients with large shunts than in those with small shunts (8.1% vs. 2.2%, p = 0.036). Multivariate analyses revealed that a large shunt was significantly associated with an increased risk of recurrent ischemic stroke [aOR 4.09 (95% CI 1.04-16.0), p = 0.043]. CONCLUSIONS: In our cohort of cryptogenic stroke patients with medically managed PFOs, those with large shunts were at a higher risk of recurrent stroke events, independently of RoPE score and left atrium diameter.

The use of colchicine as an anti-inflammatory agent for stroke prevention in patients with coronary artery disease: a systematic review and meta-analysis.

OBJECTIVE: The primary objective is to evaluate the use of colchicine as an anti-inflammatory agent for stroke prevention in patients with coronary artery disease. BACKGROUND: There has been a rising number of randomized controlled trials conducted in patients with coronary artery disease on the use of colchicine in reducing cardiovascular complications. Recent publications suggest colchicine reduces the risk of stroke and other cardiovascular events. METHODS: We performed a systematic review of known trials in the current literature to characterize the clinical characteristics and outcomes of colchicine treatment in patients with coronary artery disease. A literature search was performed in PubMed, Embase and SCOPUS using a suitable keyword search strategy from inception to 4 June 2021. All studies evaluating cardiovascular outcomes of colchicine treatment in patients with coronary artery disease were included. RESULTS: The systemic review included 5 randomized controlled trials assessing a total of 11,790 patients. Majority of studies used a colchicine dosing regimen of 0.5 mg once daily, with the median follow-up duration ranging from 6 to 36 months. Meta-analytic estimates for stroke incidence highlighted a statistically significant benefit for patients that were administered colchicine compared to placebo (OR 0.47, 95% CI 0.27-0.81, p = 0.006), and a non-significant benefit for myocardial infarction. There was no significant association between colchicine treatment and the adverse effects of gastrointestinal symptoms and myopathy/myalgia. CONCLUSIONS: The use of colchicine reduces the risk of stroke in patients with a history of coronary artery disease, without a significant increase in gastrointestinal and myopathy/myalgia adverse effects.

Effect of frailty on outcomes of endovascular treatment for acute ischaemic stroke in older patients.

BACKGROUND: frailty has been shown to be a better predictor of clinical outcomes than age alone across many diseases. Few studies have examined the relationship between frailty, stroke and stroke interventions such as endovascular thrombectomy (EVT). OBJECTIVE: we aimed to investigate the impact of frailty measured by clinical frailty scale (CFS) on clinical outcomes after EVT for acute ischemic stroke (AIS) in older patients ≥70 years. METHODS: in this retrospective cohort study, we included all consecutive AIS patients age ≥ 70 years receiving EVT at a single comprehensive stroke centre. Patients with CFS of 1-3 were defined as not frail, and CFS > 3 was defined as frail. The primary outcome was modified Rankin Score (mRS) at 90 days. The secondary outcomes included duration of hospitalisation, in-hospital mortality, carer requirement, successful reperfusion, symptomatic intracranial haemorrhage and haemorrhagic transformation. RESULTS: a total of 198 patients were included. The mean age was 78.1 years and 52.0% were female. Frail patients were older, more likely to be female, had more co-morbidities. CFS was significantly associated with poor functional outcome after adjustment for age, NIHSS and time to intervention (adjusted odds ratio [aOR] 1.54, 95% confidence interval [CI] 1.04-2.28, P = 0.032). There was trend towards higher mortality rate in frail patients (frail: 18.3%; non-frail: 9.6%; P = 0.080). There were no significant differences in other secondary outcomes except increased carer requirement post discharge in frail patients (frail: 91.6%; non-frail: 72.8%; P = 0.002). CONCLUSIONS: frailty was associated with poorer functional outcome at 90 days post-EVT in patients ≥ 70 years.

Association of triglyceride-glucose index with clinical outcomes in patients with acute ischemic stroke receiving intravenous thrombolysis.

Intravenous tissue plasminogen activator (tPA) remains the cornerstone of recanalization therapy for acute ischemic stroke (AIS), albeit with varying degrees of response. The triglyceride-glucose (TyG) index is a novel marker of insulin resistance, but association with outcomes among AIS patients who have received tPA has not been well elucidated. We studied 698 patients with AIS who received tPA from 2006 to 2018 in a comprehensive stroke centre. TyG index was calculated using the formula: ln[fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. TyG index was significantly lower in patients that survived at 90-days than those who died (8.61 [Interquartile Range: 8.27-8.99] vs 8.76 [interquartile range: 8.39-9.40], p = 0.007). In multivariate analysis, TyG index was significantly associated with 90-day mortality (OR: 2.12, 95% CI: 1.39-3.23, p = 0.001), poor functional outcome (OR: 1.41 95% CI: 1.05-1.90, p = 0.022), and negatively associated with early neurological improvement (ENI) (OR: 0.68, 95% CI: 0.52-0.89, p = 0.004). There was no association between TyG index and symptomatic intracranial hemorrhage. 'High TyG' (defined by TyG index ≥ 9.15) was associated with mortality, poor functional outcomes and no ENI. In conclusion, the TyG index, a measure of insulin resistance, was significantly associated with poorer clinical outcomes in AIS patients who received tPA.

Myocardial infarction, stroke and cardiovascular mortality among migraine patients: a systematic review and meta-analysis.

BACKGROUND: An increasing number of studies have shown an association between migraine and cardiovascular disease, in particular cardio- and cerebro-vascular events. METHODS: Three electronic databases (PubMed, Embase and Scopus) were searched from inception to May 22, 2021 for prospective cohort studies evaluating the risk of myocardial infarction, stroke and cardiovascular mortality in migraine patients. A random effects meta-analysis model was used to summarize the included studies. RESULTS: A total of 18 prospective cohort studies were included consisting of 370,050 migraine patients and 1,387,539 controls. Migraine was associated with myocardial infarction (hazard ratio, 1.36; 95% CI, 1.23-1.51; p = < 0.001), unspecified stroke (hazard ratio, 1.30; 95% CI, 1.07-1.60; p = 0.01), ischemic stroke (hazard ratio, 1.35; 95% CI, 1.03-1.78; p = 0.03) and hemorrhagic stroke (hazard ratio, 1.43; 95% CI, 1.07-1.92; p = 0.02). Subgroup analysis of migraine with aura found a further increase in risk of myocardial infarction and both ischemic and hemorrhagic stroke, as well as improved substantial statistical heterogeneity. Migraine with aura was also associated with an increased risk of cardiovascular mortality (hazard ratio, 1.27; 95% CI, 1.14-1.42; p = < 0.001). CONCLUSION: Migraine, especially migraine with aura, is associated with myocardial infarction and stroke. Migraine with aura increases the risk of overall cardiovascular mortality.

Evaluating the safety and efficacy of intravenous thrombolysis for acute ischemic stroke patients with a history of intracerebral hemorrhage: a systematic review and meta-analysis.

Previous intracerebral hemorrhage (ICH) is labelled as a contraindication for the use of intravenous tissue plasminogen activator (IV-tPA) in acute ischemic stroke (AIS) based on expert opinion. However, there is a paucity of data available regarding the benefits and risks of IV-tPA in this population. Recent small retrospective cohort studies reporting its off-label use suggest it may be beneficial. This study aims to investigate the safety and efficacy of IV-tPA in AIS patients with previous ICH. We performed a systematic review and meta-analysis of studies reporting on IV-tPA use in AIS patients with and without previous ICH. We searched Embase, PubMed and Cochrane Library from inception to 20 April 2021. Outcomes measured included symptomatic ICH (sICH), 3-month modified Rankin Scale (mRS) score, and 3-month mortality. We included seven retrospective cohort studies comprising 5760 AIS patients who had received IV-tPA, of which 134 had previous ICH. There was no significant difference in the odds of sICH (OR 1.57, 95% CI 0.78-3.15, p = 0.21) and 3-month mRS (mRS 0-1: OR 0.78, 95% CI 0.37-1.65, p = 0.52; mRS 0-2: OR 1.07, 95% CI 0.36-3.15, p = 0.90) between patients with and without previous ICH. There was a trend towards higher 3-month mortality in patients with previous ICH (OR 1.69, 95% CI 0.98-2.91, p = 0.06), although this did not reach statistical significance. The use of IV-tPA in AIS patients with previous ICH was not associated with an increased risk of sICH or disability at 3 months. Further larger studies are needed to establish the safety and efficacy of IV-tPA use in this population.

Association of Global Cardiac Calcification with Atrial Fibrillation and Recurrent Stroke in Patients with Embolic Stroke of Undetermined Source.

BACKGROUND: Calcium deposits in the heart have been associated with cardiovascular events, mortality, stroke, and atrial fibrillation (AF). However, there is no accepted standard method for scoring cardiac calcifications. Existing methods have also not been validated for the assessment of patients with embolic stroke of undetermined source (ESUS). The aim of this study was to evaluate the association of various cardiac calcification scores with new-onset AF and stroke recurrence in a cohort of patients with ESUS. METHODS: In this study, 181 consecutive patients with stroke diagnosed with ESUS were identified and evaluated. They were followed for new-onset AF and ischemic stroke recurrence for a median duration of 2.1 years. Various echocardiographic cardiac calcification scores were assessed on transthoracic echocardiography performed during the evaluation of ESUS and subsequently assessed for their relation to AF detection and recurrent stroke. The echocardiographic calcium scores assessed were the (1) global cardiac calcium score (GCCS), (2) echocardiographic calcium score (eCS), (3) echocardiographic calcification score, (4) echocardiographic composite cardiac calcium score, and (5) total heart calcification score. Only two of these scoring schemes, GCCS and eCS, quantified the cardiac calcium burden. RESULTS: Higher calcium scores as measured by GCCS and eCS were found to be significantly associated with subsequent AF detection as well as recurrent ischemic stroke in patients with ESUS. The association with recurrent stroke remained significant even after adjustment for comorbidities and AF. CONCLUSIONS: Higher cardiac calcification measured using the GCCS and eCS is independently associated with AF detection and recurrent ischemic stroke in patients with ESUS, and these scores can be useful markers for further risk stratification in patients with ESUS.

Intra-Arterial Adjunctive Medications for Acute Ischemic Stroke During Mechanical Thrombectomy: A Meta-Analysis.

BACKGROUND AND PURPOSE: In patients with acute ischemic stroke with large vessel occlusion, the role of intra-arterial adjunctive medications (IAMs), such as urokinase, tPA (tissue-type plasminogen activator), or glycoprotein IIb/IIIa inhibitors, during mechanical thrombectomy (MT) has not been clearly established. We aim to evaluate the efficacy and safety of concomitant or rescue IAM for acute ischemic stroke with large vessel occlusion patients undergoing MT. METHODS: We searched Medline, Embase, and Cochrane Stroke Group Trials Register databases from inception until March 13, 2020. We analyzed all studies with patients diagnosed with acute ischemic stroke with large vessel occlusion in the anterior or posterior circulation that provided data for the two treatment arms, (1) MT+IAM and (2) MT only, and also reported on at least one of the following efficacy outcomes, recanalization and 90-day modified Rankin Scale, or safety outcomes, symptomatic intracranial hemorrhage and 90-day mortality. Data were collated in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Sixteen nonrandomized observational studies with a total of 4581 patients were analyzed. MT only was performed in 3233 (70.6%) patients, while 1348 (29.4%) patients were treated with both MT and IAM. As compared with patients treated with MT alone, patients treated with combination therapy (MT+IAM) had a higher likelihood of achieving good functional outcome (risk ratio, 1.13 [95% CI, 1.03-1.24]) and a lower risk of 90-day mortality (risk ratio, 0.82 [95% CI, 0.72-0.94]). There was no significant difference in successful recanalization (risk ratio, 1.02 [95% CI, 0.99-1.06]) and symptomatic intracranial hemorrhage between the two groups (risk ratio, 1.13 [95% CI, 0.87-1.46]). CONCLUSIONS: In acute ischemic stroke with large vessel occlusion, the use of IAM together with MT may achieve better functional outcomes and lower mortality rates. Randomized controlled trials are warranted to establish the safety and efficacy of IAM as adjunctive treatment to MT.

Predicting Clinical Outcomes in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy with Machine Learning : A Systematic Review and Meta-analysis.

PURPOSE: Conventional predictive models are based on a combination of clinical and neuroimaging parameters using traditional statistical approaches. Emerging studies have shown that the machine learning (ML) prediction models with multiple pretreatment clinical variables have the potential to accurately prognosticate the outcomes in acute ischemic stroke (AIS) patients undergoing thrombectomy, and hence identify patients suitable for thrombectomy. This article summarizes the published studies on ML models in large vessel occlusion AIS patients undergoing thrombectomy. METHODS: We searched electronic databases including PubMed from 1 January 2000 up to 14 October 2019 for studies that evaluated ML algorithms for the prediction of outcomes in stroke patients undergoing thrombectomy. We then used random-effects bivariate meta-analysis models to summarize the studies. RESULTS: We retained a total of five studies that evaluated ML (4 support vector machine, 1 decision tree model) with a combined cohort of 802 patients. The prevalence of good functional outcome defined by 90-day mRS of 0-2 when available. Random effects model demonstrated that the AUC was 0.846 (95% confidence interval, CI 0.686-0.902). A pooled diagnostic odds ratio of 12.6 was computed. The pooled sensitivity and specificity were 0.795 (95% CI 0.651-0.889) and 0.780 (95% CI 0.634-0.879), respectively. CONCLUSION: ML may be useful as an adjunct to clinical assessment to predict functional outcomes in AIS patients undergoing thrombectomy, and hence identify suitable patients for treatment. Further studies validating ML models in large multicenter cohorts are necessary to explore this further.

Association of Electrocardiographic P-Wave Markers and Atrial Fibrillation in Embolic Stroke of Undetermined Source.

BACKGROUND: Several P-wave indices are thought to represent underlying atrial remodeling and have been associated with ischaemic stroke even in the absence of atrial fibrillation (AF). However, the utility of these P-wave indices in predicting outcomes in patients with embolic stroke of undetermined source (ESUS) has not been studied. The aim of this study is to examine these different P-wave indices towards predicting new-onset AF and stroke recurrence in a cohort of patients with ESUS, thereby demonstrating the value of these electrocardiographic markers for stroke risk stratification. METHODS: Between October 2014 and October 2017, consecutive patients diagnosed with ESUS were followed for new-onset AF and ischaemic stroke recurrence. The various P-wave indices, namely, the P-terminal force in the precordial lead V1 (PTFV1), P-wave duration, P-wave dispersion, interatrial blocks, and P-wave axis, were assessed on the initial electrocardiogram on presentation and studied for their relation to eventual AF detection and recurrent stroke. RESULTS: 181 ischaemic stroke patients with ESUS were recruited and followed up for a median duration of 2.1 years. An abnormal PTFV1 was associated with occult AF detection but not with recurrent ischaemic strokes. No significant association was observed between the other P-wave indices with either occult AF or stroke recurrence. CONCLUSION: PTFV1 is associated with AF detection but not recurrent strokes in ESUS patients and can be a useful electrocardiographic marker for further risk stratification in ESUS patients.

Powered Air Purifying Respirator (PAPR) restores the N95 face mask induced cerebral hemodynamic alterations among Healthcare Workers during COVID-19 Outbreak.

BACKGROUND AND AIM: COVID-19 pandemic has resulted in an unprecedented increased usage of Personal protective equipment (PPE) by healthcare-workers. PPE usage causes headache in majority of users. We evaluated changes in cerebral hemodynamics among healthcare-workers using PPE. METHODS: Frontline healthcare-workers donning PPE at our tertiary center were included. Demographics, co-morbidities and blood-pressure were recorded. Transcranial Doppler (TCD) monitoring of middle cerebral artery was performed with 2-MHz probe. Mean flow velocity (MFV) and pulsatility index (PI) were recorded at baseline, after donning N95 respirator-mask, and after donning powered air-purifying respirator (PAPR), when indicated. End-tidal carbon-dioxide (ET-CO2) pressure was recorded for participants donning PAPR in addition to the N95 respirator-mask. RESULTS: A total of 154 healthcare-workers (mean age 29 ± 12 years, 67% women) were included. Migraine was the commonest co-morbidity in 38 (25%) individuals while 123 (80%) developed de-novo headache due to N95 mask. Donning of N95 respirator-mask resulted in significant increase in MFV (4.4 ± 10.4 cm/s, p < 0.001) and decrease in PI (0.13 ± 0.12; p < 0.001) while ET-CO2 increased by 3.1 ± 1.2 mmHg (p < 0.001). TCD monitoring in 24 (16%) participants donning PAPR and N95 respirator mask together showed normalization of PI, accompanied by normalization of ET-CO2 values within 5-min. Combined use of N95 respirator-mask and PAPR was more comfortable as compared to N95 respirator-mask alone. CONCLUSION: Use of N95 respirator-mask results in significant alterations in cerebral hemodynamics. However, these effects are mitigated by the use of additional PAPR. We recommend the use of PAPR together with the N95 mask for healthcare-workers doing longer duties in the hospital wards.

COVID-19 and ischemic stroke: a systematic review and meta-summary of the literature.

Acute ischemic stroke (AIS) is a life-threatening complication of coronavirus disease 2019 (COVID-19) infection. Increasing reports suggest an association between COVID-19 and AIS, although the underlying mechanism remains uncertain. We performed a systematic review to characterize the clinical characteristics, neuroimaging findings, and outcomes of AIS in COVID-19 patients. A literature search was performed in PubMed and Embase using a suitable keyword search strategy from 1st December 2019 to 29th May 2020. All studies reporting AIS occurrence in COVID-19 patients were included. A total of 39 studies comprising 135 patients were studied. The pooled incidence of AIS in COVID-19 patients from observational studies was 1.2% (54/4466) with a mean age of 63.4 ± 13.1 years. The mean duration of AIS from COVID-19 symptoms onset was 10 ± 8 days, and the mean NIHSS score was 19 ± 8. Laboratory investigations revealed an elevated mean D-dimer (9.2 ± 14.8 mg/L) and fibrinogen (5.8 ± 2.0 g/L). Antiphospholipid antibodies were detected in a significant number of cases. The majority of AIS neuroimaging patterns observed was large vessel thrombosis, embolism or stenosis (62.1%, 64/103), followed by multiple vascular territory (26.2%, 27/103). A high mortality rate was reported (38.0%, 49/129). We report the pooled incidence of AIS in COVID-19 patients to be 1.2%, with a high mortality rate. Elevated D-dimer, fibrinogen and the presence of antiphospholipid antibodies appear to be prominent in COVID-19 patients with concomitant AIS, but further mechanistic studies are required to elucidate their role in pathogenesis.

Impact of the COVID-19 pandemic on hyperacute stroke treatment: experience from a comprehensive stroke centre in Singapore.

The Coronavirus disease 2019 (COVID-19) pandemic is rapidly evolving and affecting healthcare systems across the world. Singapore has escalated its alert level to Disease Outbreak Response System Condition (DORSCON) Orange, signifying severe disease with community spread. We aimed to study the overall volume of AIS cases and the delivery of hyperacute stroke services during DORSCON Orange. This was a single-centre, observational cohort study performed at a comprehensive stroke centre responsible for AIS cases in the western region of Singapore, as well as providing care for COVID-19 patients. All AIS patients reviewed as an acute stroke activation in the Emergency Department (ED) from November 2019 to April 2020 were included. System processes timings, treatment and clinical outcome variables were collected. We studied 350 AIS activation patients admitted through the ED, 206 (58.9%) pre- and 144 during DORSCON Orange. Across the study period, number of stroke activations showed significant decline (p = 0.004, 95% CI 6.513 to - 2.287), as the number of COVID-19 cases increased exponentially, whilst proportion of activations receiving acute recanalization therapy remained stable (p = 0.519, 95% CI - 1.605 to 2.702). Amongst AIS patients that received acute recanalization therapy, early neurological outcomes in terms of change in median NIHSS at 24 h (-4 versus -4, p = 0.685) were largely similar between the pre- and during DORSCON orange periods. The number of stroke activations decreased while the proportion receiving acute recanalization therapy remained stable in the current COVID-19 pandemic in Singapore.