Long-term cognitive and neurovascular changes after carotid endarterectomy.

BACKGROUND: Carotid endarterectomy (CEA) has been associated with both cognitive decline and improvement, but the underlying neurovascular mechanisms are unclear. The aim of this study was to investigate the relationship between neurovascular indices and cognitive changes after CEA. METHODS: We studied 55 patients with severe (≥70%) symptomatic or asymptomatic carotid stenosis before and six months after CEA. A wide array of neuropsychological tests was arranged in eight cognitive domains and cognitive functions specific to hemisphere ipsilateral to operation. Differences in cognitive performance between patients and 38 matching healthy controls were studied with linear mixed models. Neurovascular functioning and microembolic signals were assessed with transcranial Doppler ultrasound of the middle cerebral artery. Associations between neurovascular indices and cognitive change were assessed with linear regression analyses. RESULTS: On group level, the CEA patients improved more than controls in working memory, whereas no cognitive deterioration was detected. Also on individual level, improvement was most frequently observed in working memory. Worse preoperative cerebrovascular reactivity was related with improvement in cognitive functions of the ipsilateral hemisphere. Low preoperative pulsatility index was associated with improvement in executive functioning and ipsilateral cognitive functions. Poorer preoperative blood flow velocity associated with improvement in complex attention. Microembolic signals were rare. CONCLUSION: The present findings suggest that CEA may have beneficial long-term effects on cognition. These effects may specifically involve patients with impaired preoperative circulatory adaptive mechanisms.

IV Thrombolysis in Basilar Artery Occlusion: Outcomes and Comparison With Endovascular Thrombectomy.

BACKGROUND AND OBJECTIVES: Recanalization is considered a prerequisite for favorable outcome in basilar artery occlusion (BAO). Intravenous thrombolysis (IVT) has been successfully used for eligible patients with BAO well beyond the 4.5-hour time window but has been largely underrepresented in the best medical management arms in recent randomized controlled trials of recanalization therapy in BAO. We aimed to analyze the outcomes of patients with BAO treated with IVT only and to compare IVT with endovascular thrombectomy (EVT). METHODS: This observational single-center, retrospective cohort study included consecutive patients with BAO treated with IVT and/or EVT up to 48 hours of symptom onset during 1995-2022. The primary outcome was favorable functional outcome (modified Rankin Scale 0-3) at 3 months collected by a stroke physician by phone. In the first part, we described the outcomes and factors associated with functional outcome in the IVT-only cohort during 1995-2022. In the second part, we used doubly robust inverse probability-weighted regression adjustment models to compare functional outcome of patients treated with IVT vs EVT+/-IVT during 2010-2022. RESULTS: In the whole cohort of 376 patients with acute BAO treated with recanalization therapy, 245 (65.2%) received only IVT. In the IVT-only cohort, most patients had moderate-to-severe clinical presentation (median NIH Stroke Scale 18) but no extensive early ischemic changes in the posterior circulation on admission. Half of them had onset-to-treatment time over 6 hours. 46.5% of the IVT-treated patients achieved 3-month favorable functional outcome, whereas mortality was 35.9%. sICH occurred in 11.1%. In a multivariable analysis, younger age, milder symptom severity, and less baseline ischemic changes predicted favorable functional outcome. In the 2010-2022 cohort, when compared with patients treated with EVT+/-IVT (n = 121), the IVT-only cohort (n = 122) had higher odds for favorable functional outcome (IVT 58.2% vs EVT 43.0% (aOR 2.82 [95% CI 1.31-6.05]). DISCUSSION: IVT alone produced outcomes comparable with those in recent trials of endovascular BAO recanalization. Furthermore, in head-to-head comparison in our cohort, the IVT-only approach was more often associated with favorable outcome than EVT+/-IVT. Thus, it should not be overlooked as the first-line recanalization therapy in acute BAO, even in longer time windows. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that tPA is as effective as thrombectomy for basilar artery thrombosis.

MANF protein expression is upregulated in immune cells in the ischemic human brain and systemic recombinant MANF delivery in rat ischemic stroke model demonstrates anti-inflammatory effects.

Mesencephalic astrocyte-derived neurotrophic factor (MANF) has cytoprotective effects on various injuries, including cerebral ischemia, and it can promote recovery even when delivered intracranially several days after ischemic stroke. In the uninjured rodent brain, MANF protein is expressed almost exclusively in neurons, but post-ischemic MANF expression has not been characterized. We aimed to investigate how endogenous cerebral MANF protein expression evolves in infarcted human brains and rodent ischemic stroke models. During infarct progression, the cerebral MANF expression pattern both in human and rat brains shifted drastically from neurons to expression in inflammatory cells. Intense MANF immunoreactivity took place in phagocytic microglia/macrophages in the ischemic territory, peaking at two weeks post-stroke in human and one-week post-stroke in rat ischemic cortex. Using double immunofluorescence and mice lacking MANF gene and protein from neuronal stem cells, neurons, astrocytes, and oligodendrocytes, we verified that MANF expression was induced in microglia/macrophage cells in the ischemic hemisphere. Embarking on the drastic expression transition towards inflammatory cells and the impact of blood-borne inflammation in stroke, we hypothesized that exogenously delivered MANF protein can modulate tissue recovery processes. In an attempt to enhance recovery, we designed a set of proof-of-concept studies using systemic delivery of recombinant MANF in a rat model of cortical ischemic stroke. Intranasal recombinant MANF treatment decreased infarct volume and reduced the severity of neurological deficits. Intravenous recombinant MANF treatment decreased the levels of pro-inflammatory cytokines and increased the levels of anti-inflammatory cytokine IL-10 in the infarcted cortex one-day post-stroke. In conclusion, MANF protein expression is induced in activated microglia/macrophage cells in infarcted human and rodent brains, and this could implicate MANF's involvement in the regulation of post-stroke inflammation in patients and experimental animals. Moreover, systemic delivery of recombinant MANF shows promising immunomodulatory effects and therapeutic potential in experimental ischemic stroke.

Retinal vessel diameters and microvascular abnormalities in patients with carotid stenosis before and 6 months after carotid endarterectomy: A prospective study.

PURPOSE: To assess retinal findings in patients with severe carotid stenosis (CS) before and after carotid endarterectomy (CEA) compared to those in controls. METHODS: This study is based on 70 patients (male 81%, mean age 69) scheduled for CEA in Helsinki University Hospital and 41 healthy nonmedicated controls (male 76%, mean age 68). Our examinations included fundus photographs. Semi-automated software (Vesselmap, Imedos) served for evaluation of central retinal arterial equivalent (CRAE) and venular equivalent (CRVE), and arterio-venous ratio (AVR) in both eyes. We assessed fundus photographs to subjectively grade microvascular abnormalities in the ipsilateral eyes including focal arteriolar narrowing and irregularities, arteriolar wall reflex, arterio-venous crossing signs and arteriolar and venular tortuosity in the macula. RESULTS: CRAE was similar in the ipsi-and contralateral eyes of our patients, and similar to that of the controls both pre- and postoperatively. Preoperatively, we observed higher CRVE in the patients' ipsilateral than in their contralateral eyes (222 vs. 217 µm, p = 0.009), and likewise higher than in controls' eyes (222 vs. 214 µm, p = 0.024). CRVE decreased postoperatively in the patients' ipsilateral eyes (222 vs. 217 µm, p = 0.037). Among the microvascular abnormalities, arteriolar and venular tortuosity in the macula showed higher grades in the patients than in the controls preoperatively (p = 0.035 and p = 0.043), but not postoperatively (p = 0.15 and p = 0.10). CONCLUSIONS: CRVE decreased after CEA, showing that venules constrict after the mechanical hindrance of blood flow is removed. Higher grades in arteriolar and venular tortuosity in the macula, a potential ocular biomarker of CS, subsided after CEA.

Glutamine synthetase in human carotid plaque macrophages associates with features of plaque vulnerability: An immunohistological study.

BACKGROUND AND AIMS: Glutamine synthetase (GLUL), the sole generator of glutamine, is a metabolic nexus molecule also involved in atherosclerosis. We recently demonstrated a 2.2-fold upregulation of GLUL mRNA in stroke-causing carotid plaques when compared with plaques from asymptomatic patients. Here we compared in the same cohort GLUL mRNA expression with plaque gross morphology, and the colocalization of immunodetectable GLUL protein with histopathological changes and molecular and mechanical mediators linked to plaque development. METHODS: Endarterectomy specimens from 19 asymptomatic and 24 stroke patients were sectioned longitudinally and immunostained for GLUL, CD68, α-smooth muscle actin, iron, heme oxygenase-1 and CD163, and graded semiquantitatively in every 1 mm2. The amounts of cholesterol clefts and erythrocytes were graded. The fibrous cap thickness within each 1 mm2 area was measured. The association between the local pathological findings was analyzed by a hierarchical mixed modelling approach. RESULTS: The previously found correlation between GLUL mRNA and clinical symptomatology was supported by the increased GLUL mRNA in diseased tissue and increased local GLUL immunoreactivity in areas with multiple different atherosclerotic changes. A longer symptom-to-operation time correlated with lower GLUL mRNA (Rs = -0.423, p=0.050) but few outliers had a significantly higher GLUL mRNA levels, which persisted throughout the post-symptomatic period. Plaque ulceration associated with 1.8-fold higher GLUL mRNA (p=0.006). Macrophages were the main GLUL immunoreactive cells. GLUL immunostaining colocalized with erythrocytes, iron, CD163, and heme oxygenase-1. The correlations between local variables were consistent in both asymptomatic and stroke-causing plaques. An inverse correlation was found between the fibrous cap thickness and local GLUL immunoreactivity (p=0.012). Considerable variability in interplaque expression pattern of GLUL was present. CONCLUSIONS: Our results link connect macrophage GLUL expression with carotid plaque features characterizing plaque vulnerability.

Differential Cognitive Functioning and Benefit From Surgery in Patients Undergoing Coronary Artery Bypass Grafting and Carotid Endarterectomy.

Background: Stenosing atherosclerosis in both coronary and carotid arteries can adversely affect cognition. Also their surgical treatments, coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA), are associated with cognitive changes, but the mechanisms of cognitive decline or improvement may not be the same. This study was designed to compare the cognitive profile and outcome in patients undergoing surgical treatment for coronary or carotid disease. Methods: A total of 100 CABG patients and 44 CEA patients were recruited in two previously reported studies. They were subjected to a comprehensive neuropsychological examination prior to surgery and in the acute (3-8 days) and stable (3 months) phase after operation. A group of 17 matched healthy controls were assessed with similar intervals. We used linear mixed models to compare cognitive trajectories within six functional domains between the CABG, CEA and control groups. Postoperative cognitive dysfunction (POCD) and improvement (POCI) were determined with the reliable change index method in comparison with healthy controls. Results: Before surgery, the CEA patients performed worse than CABG patients or healthy controls in the domains of executive functioning and processing speed. The CABG patients exhibited postoperative cognitive dysfunction more often than the CEA patients in most cognitive domains in the acute phase but had regained their performance in the stable phase. The CEA patients showed more marked postoperative improvement in executive functioning than the CABG group in the acute phase, but the difference did not reach significance in the stable phase. Conclusion: Our findings suggest that anterior cerebral dysfunction in CEA patients impairs preoperative cognition more severely than global brain dysfunction in CABG patients. However, CEA may have more beneficial effects on cognition than CABG, specifically in executive functions mainly operated by the prefrontal lobes. In addition, the results underline that POCD is a heterogeneous condition and dependent on type of revascularization surgery.

Flicker-induced retinal vascular dilation in ipsi- and contralateral eyes of patients with carotid stenosis before and after carotid endarterectomy: a prospective study.

PURPOSE: Retinal vascular function was assessed in patients with carotid stenosis (CS) before and six months after carotid endarterectomy (CEA) and in controls at a six-month interval. METHODS: We studied 68 patients (81% male, mean age 69) and 41 healthy non-medicated controls (77%, 68) from March 2015 to December 2018. Our ophthalmological examination included flicker-induced arteriolar and venular measurements with a Dynamic Vessel Analyser in both eyes. RESULTS: At baseline, flicker-induced arteriolar and venular dilation was reduced in the ipsilateral eyes of the patients compared with dilation in the controls (arteriolar 1.0% versus 2.6%, p = 0.001 and venular 2.2% versus 2.8%, p = 0.049). These differences subsided after CEA. In patients' ipsilateral eyes, flicker-induced arteriolar dilation was borderline postoperatively (preoperative 1.0% versus postoperative 1.6%, p = 0.06), whereas venular dilation increased (2.2% versus 2.8%, p = 0.025). We found various tentative associations with the change in flicker-induced dilations after CEA, but not with the preoperative dilations. CONCLUSIONS: Postoperative recovery of the reduced flicker-induced arteriolar and venular dilatation in the ipsilateral eye shows that, after CEA, the activity-dependent vascular reactivity of haemodynamically compromised retinal tissue can improve.

Ocular signs of carotid stenosis in ipsi- and contralateral eyes before and after carotid endarterectomy: a prospective study.

PURPOSE: We describe hypoperfusion-related and embolic ocular signs of carotid stenosis (CS) before and six months after carotid endarterectomy (CEA) in a CS population. METHODS: We enrolled prospectively 70 CEA patients (81% male, mean age 69) and 41 non-medicated control subjects (76%, 68), from March 2015 to December 2018, assessing intraocular pressure (IOP), best-corrected visual acuity (BCVA) in logMAR units and performing a bio-microscopy examination. RESULTS: Main index symptoms included amaurosis fugax (Afx) (29, 41%) and hemispheric TIA (17, 24%), and 17 (24%) were asymptomatic. Of the 70, 17 patients (24%, 95% CI 16-36) showed ocular signs of CS. Of four embolic (Hollenhorst plaques) findings, one small macular plaque disappeared postoperatively. Four had hypoperfusion, that is ocular ischaemic syndrome (OIS), requiring panretinal photocoagulation: one for multiple mid-peripheral haemorrhages, two for iris neovascularization and one for neovascular glaucoma (NVG); only the NVG proved irreversible. Nine (de novo in three) showed mild OIS, that is only few mid-peripheral haemorrhages, ranging pre- /postoperatively in ipsilateral eyes from one to eleven (median two)/ one to two (median one), and in contralateral eyes from three to nine (median five)/ one to six (median three). Pre- and postoperative median BCVA was 0 or better, and mean IOP was normal, except in the NVG patient. Temporary visual impairment from 0 to 0.3 occurred in one eye soon after CEA due to ocular hyperperfusion causing macular oedema. CONCLUSIONS: Ocular signs of CS are common in CEA patients, ranging from few mid-peripheral haemorrhages to irreversible NVG. Clinicians should be aware of these signs in detecting CS.

Ultra-Early Differential Diagnosis of Acute Cerebral Ischemia and Hemorrhagic Stroke by Measuring the Prehospital Release Rate of GFAP.

BACKGROUND: Plasma glial fibrillary acidic protein (GFAP) and tau are promising markers for differentiating acute cerebral ischemia (ACI) and hemorrhagic stroke (HS), but their prehospital dynamics and usefulness are unknown. METHODS: We performed ultra-sensitivite single-molecule array (Simoa®) measurements of plasma GFAP and total tau in a stroke code patient cohort with cardinal stroke symptoms [National Institutes of Health Stroke Scale (NIHSS) ≥3]. Sequential sampling included 2 ultra-early samples, and a follow-up sample on the next morning. RESULTS: We included 272 cases (203 ACI, 60 HS, and 9 stroke mimics). Median (IQR) last-known-well to sampling time was 53 (35-90) minutes for initial prehospital samples, 90 (67-130) minutes for secondary acute samples, and 21 (16-24) hours for next morning samples. Plasma GFAP was significantly higher in patients with HS than ACI (P < 0.001 for <1 hour and <3 hour prehospital samples, and <3 hour secondary samples), while total tau showed no intergroup difference. The prehospital GFAP release rate (pg/mL/minute) occurring between the 2 very early samples was significantly higher in patients with HS than ACI [2.4 (0.6-14.1)] versus 0.3 (-0.3-0.9) pg/mL/minute, P < 0.001. For cases with <3 hour prehospital sampling (ACI n = 178, HS n = 59), a combined rule (prehospital GFAP >410 pg/mL, or prehospital GFAP 90-410 pg/mL together with GFAP release >0.6 pg/mL/minute) enabled ruling out HS with high certainty (NPV 98.4%) in 68% of patients with ACI (sensitivity for HS 96.6%, specificity 68%, PPV 50%). CONCLUSIONS: In comparison to single-point measurement, monitoring the prehospital GFAP release rate improves ultra-early differentiation of stroke subtypes. With serial measurement GFAP has potential to improve future prehospital stroke diagnostics.

The Low-Expression Variant of FABP4 Is Associated With Cardiovascular Disease in Type 1 Diabetes.

Fatty acid binding protein 4 (FABP4) is implicated in the pathogenesis of cardiometabolic disorders. Pharmacological inhibition or genetic deletion of FABP4 improves cardiometabolic health and protects against atherosclerosis in preclinical models. As cardiovascular disease (CVD) is common in type 1 diabetes, we examined the role of FABP4 in the development of complications in type 1 diabetes, focusing on a functional, low-expression variant (rs77878271) in the promoter of the FABP4 gene. For this, we assessed the risk of CVD, stroke, coronary artery disease (CAD), end-stage kidney disease, and mortality using Cox proportional hazards models for the FABP4 rs77878271 in 5,077 Finnish individuals with type 1 diabetes. The low-expression G allele of rs77878271 increased the risk of CVD, independent of confounders. Findings were tested for replication in 852 Danish and 3,678 Finnish individuals with type 1 diabetes. In the meta-analysis, each G allele increased the risk of stroke by 26% (P = 0.04), CAD by 26% (P = 0.006), and CVD by 17% (P = 0.003). In Mendelian randomization, a 1-SD unit decrease in FABP4 increased risk of CAD 2.4-fold. Hence, in contrast with the general population, among patients with type 1 diabetes the low-expression G allele of rs77878271 increased CVD risk, suggesting that genetically low FABP4 levels may be detrimental in the context of type 1 diabetes.

Warfarin Treatment Is Associated to Increased Internal Carotid Artery Calcification.

Background: Long-term treatment with the vitamin K antagonist warfarin is widely used for the prevention of venous thrombosis and thromboembolism. However, vitamin K antagonists may promote arterial calcification, a phenomenon that has been previously studied in coronary and peripheral arteries, but not in extracranial carotid arteries. In this observational cohort study, we investigated whether warfarin treatment is associated with calcification of atherosclerotic carotid arteries. Methods: Overall, 500 consecutive patients underwent carotid endarterectomy, 82 of whom had received long-term warfarin therapy. The extent of calcification was assessed with preoperative computed tomography angiography, and both macroscopic morphological grading and microscopic histological examination of each excised carotid plaque were performed after carotid endarterectomy. Results: Compared with non-users, warfarin users had significantly more computed tomography angiography-detectable vascular calcification in the common carotid arteries (odds ratio 2.64, 95% confidence interval 1.51-4.63, P < 0.001) and even more calcification in the internal carotid arteries near the bifurcation (odds ratio 18.27, 95% confidence interval 2.53-2323, P < 0.001). Histological analysis revealed that the intramural calcified area in plaques from warfarin users was significantly larger than in plaques from non-users (95% confidence interval 3.36-13.56, P = 0.0018). Conclusions: Long-lasting warfarin anticoagulation associated with increased calcification of carotid atherosclerotic plaques, particularly in locations known to be the predilection sites of stroke-causing plaques. The clinical significance of this novel finding warrants further investigations.

Comatose With Basilar Artery Occlusion: Still Odds of Favorable Outcome With Recanalization Therapy.

Background: Around 30-60% of patients with basilar artery occlusion (BAO) present with coma, which is often considered as a hallmark of poor prognosis. Aim: To examine factors that will help predict outcomes in patients with BAO comatose on admission. Methods: A total of 312 patients with angiography-proven BAO were analyzed. Comas were assessed as Glasgow Coma Scale (GCS) of ≤8 or impaired level of consciousness ascertained in the medical records. Outcomes were evaluated with the modified Rankin Scale (mRS) over a phone call at 3 months. In our study, 53 patients were excluded due to inadequate data on the level of consciousness. Results: In total, 103/259 (39.8%) of BAO patients were comatose on admission. Factors associated with acute coma were higher age, coronary artery disease, convulsions, extent of early ischemia by posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) < 8, absence of patent posterior collateral vasculature, and occlusion over multiple segments of BA. A total of 21/103 (20.4%) of comatose patients had a favorable outcome (mRS 0-3), and 12/103 (11.7%) had a good outcome (mRS 0-2). Factors associated with a favorable outcome in comatose BAO patients were younger age (p = 0.010), less extensive baseline ischemia (p = 0.027), recanalization (p = 0.013), and avoiding symptomatic intracranial hemorrhage (sICH) (p = 0.038). Factors associated with the poorest outcome or death (mRS 5-6) were older age (p = 0.001), diabetes (p = 0.022), atrial fibrillation (p = 0.016), lower median GCS [4 (IQR 3.6) vs. 6 (5-8); p = 0.006], pc-ASPECTS < 8 (p = 0.003), unsuccessful recanalization (p = 0.006), and sICH (p = 0.010). Futile recanalization (mRS 4-6) was significantly more common in comatose patients (49.4 vs. 18.5%, p < 0.001). Conclusions: One in five BAO patients with acute coma had a favorable outcome. Older patients with cardiovascular comorbidities and already existing ischemic lesions before reperfusion therapies tended to have a poor prognosis, especially if no recanalization is achieved and sICH occurred.

Subfoveal choroidal thickness in ipsi- and contralateral eyes of patients with carotid stenosis before and after carotid endarterectomy: a prospective study.

PURPOSE: To compare subfoveal choroidal thickness (SFCT) and associated clinical variables in patients with carotid stenosis (CS) before and 6 months after carotid endarterectomy (CEA). METHODS: The prospective non-randomized Helsinki Carotid Endarterectomy Study - Brain and Eye Sub-sTudy included seventy patients (81% male, mean age 69 years) and 40 control subjects (77% male, 68 years), from March 2015 to December 2018. Ophthalmological examination included SFCT measured with enhanced-depth imaging-optical coherence tomography. Carotid stenosis (CS) was more severe (≥70% stenosis in 92%) ipsilateral to the CEA than contralaterally (<50% stenosis in 74%; p < 0.001). RESULTS: At baseline, patients had thinner mean SFCT than control subjects in both eyes (ipsilateral, 222 versus 257 µm and contralateral, 217 versus 258 µm, p ≤ 0.005). At follow-up, SFCT did not change in ipsi- and contralateral eyes compared to baseline in patients (p = 0.68 and p = 0.77), or in control subjects (p = 0.59 and p = 0.79). Patients with coronary artery disease had thinner mean SFCT versus those without it in ipsilateral eyes before CEA (200 versus 233 µm, p = 0.027). In ipsilateral eyes of patients before CEA, thinner SFCT and ocular signs of CS, plaque and hypoperfusion related findings combined, were associated (p = 0.036), and the best-corrected visual acuity, measured in logMAR, increased with increasing SFCT (r = -0.25; p = 0.046). CONCLUSIONS: Subfoveal choroidal thickness (SFCT) is thinner in patients with CS without association between SFCT and the grade of CS. Unchanged SFCT after CEA suggests, that choroidal vessels in severe CS are unable to react to increased blood flow. Bilaterally thin SFCT could be considered as yet another sign of CS.

Outcomes and long-term mortality after basilar artery occlusion-A cohort with up to 20 years' follow-up.

BACKGROUND: The data on long-term outcome after basilar artery occlusion (BAO) are scarce. Little is known about BAO survivors´ outcome over decades. AIM: We set out to investigate long-term survival and causes of death in BAO patients with up to two decades of follow-up. We also evaluated differences in outcome trends. METHODS: Two hundred and seven BAO patients treated with intravenous thrombolysis (IVT) at the Department of Neurology, Helsinki University Hospital, between 1995 and 2016, were analyzed. Short-term outcome was assessed by modified Rankin Scale (mRS) at 3 months. Long-term cumulative survival rate was analyzed using Kaplan-Meier analysis. Factors associated with mortality were analyzed with Cox regression. RESULTS: Moderate outcome (mRS 0-3) was achieved in 41.1% and good outcome (mRS 0-2) in 30.4% of patients at 3 months. Three-month mortality was 39.6%, of which 89% died within the first month. The median follow-up time in 3-month survivors was 8.9 years (maximum 21.8 years). Total mortality during follow-up was 52.2%. Cumulative mortality rate was 25.7%. Older age, coronary artery disease and more extensive ischemic changes on admission brain imaging were independently associated with long-term mortality. After the acute phase, the rate of other vascular causes of death increased in relation to stroke. CONCLUSIONS: The described evolution of a large, single-center BAO cohort shows a trend towards a higher rate of good and/or moderate outcome during later years in IVT-treated patients. Survivors showed relative longevity, and the rate of cardiac and other vascular causes of death increased in relation to stroke sequelae over the long term.

Predictive Factors for Pre-operative Recurrence of Cerebrovascular Symptoms in Symptomatic Carotid Stenosis.

OBJECTIVE: Across stroke subtypes, carotid artery stroke carries the highest risk of recurrence. Despite initiation of best medical therapy (BMT), some patients suffer recurrent neurological events before undergoing carotid endarterectomy (CEA). The aim was to identify clinical predictors of early recurrent events in patients with symptomatic carotid stenosis (sCS) awaiting CEA on modern BMT. METHODS: The Helsinki Carotid Endarterectomy Study 2 (HeCES2) is a cross sectional, longitudinal, prospective, and consecutive cohort study, which enrolled 500 symptomatic or asymptomatic patients with carotid stenosis scheduled for CEA in a tertiary stroke centre. Symptomatic patients were included for this analysis (n = 324). RESULTS: Of all 324 patients with sCS, 39 (12%) had a recurrent cerebrovascular event at a median of six days after the index symptom: four had an ischaemic stroke (1.2%), 16 a hemispheric transient ischaemic attack (TIA; 4.9%), and 19 amaurosis fugax (AFX; 5.9%). The recurrence rate was 4.0 % (n = 13) within 48 h and 9.9% (n = 32) within two weeks. None of the patients (n = 108) presenting with ocular symptoms (AFX or retinal artery occlusion) suffered recurrent hemispheric TIA or stroke. In Cox regression analysis, comorbid hypertension (hazard ratio [HR] 6.58, 95% confidence interval [CI] 1.33-32.47), hemispheric TIA as the index symptom (HR 3.42, 95% CI 1.70-6.90), the number of prior attacks (HR 1.12, 95% CI 1.08-1.15), and high low density lipoprotein/high density lipoprotein ratio (HR 1.51, 95% CI 1.09-2.11) were independently associated with an increased risk of recurrent event, while a history of major cardiovascular event (HR 0.33, 95% CI 0.11-0.96) and high serum fibrinogen level (HR 0.59, 95% CI 0.41-0.86) were associated with a decreased risk. CONCLUSION: More than every tenth patient with sCS experienced an early recurrent cerebrovascular event prior to scheduled CEA, despite optimal medication. However, stroke recurrence was lower than in earlier observational studies, which could be explained by improved care pathways, more aggressive medication, and expedited CEA. All recurrent strokes occurred in patients initially presenting with minor stroke.

Cognitive Dysfunction and Mortality After Carotid Endarterectomy.

Background: Carotid endarterectomy (CEA) has been associated with both postoperative cognitive dysfunction (POCD) and improvement (POCI). However, the prognostic significance of postoperative cognitive changes related to CEA is largely unknown. The aim of this study was to examine the associations between postoperative cognitive changes after CEA and long-term survival. Methods: We studied 43 patients 1 day before CEA as well as 4 days and 3 months after surgery with an extensive neuropsychological test array, and followed them for up to 14 years. POCD and POCI relative to baseline were determined with the reliable change index derived from 17 healthy controls. Associations between POCD/POCI and mortality within the patient group were studied with Cox regression analyses adjusted for confounders. Results: POCD in any functional domain was evident in 28% of patients 4 days after surgery and in 33% of patients 3 months after surgery. POCI was shown in 23% of patients at 4 days and in 44% of patients at 3 months. POCD at 3 months was associated with higher long-term mortality (hazard ratio 5.0, 95% CI 1.8-13.9, p = 0.002) compared with patients with no cognitive decline. Conclusions: Our findings suggest that POCD in a stable phase, 3 months after CEA predicts premature death. Evaluation of postoperative cognitive changes is essential, and POCD in a stable phase after CEA should prompt scrutiny of underlying factors and better adherence to therapies to prevent recurrences and to promote early intervention in imminent deterioration.

Meningeal Mast Cells Contribute to ATP-Induced Nociceptive Firing in Trigeminal Nerve Terminals: Direct and Indirect Purinergic Mechanisms Triggering Migraine Pain.

Peripheral mechanisms of primary headaches such as a migraine remain unclear. Meningeal afferents surrounded by multiple mast cells have been suggested as a major source of migraine pain. Extracellular ATP released during migraine attacks is a likely candidate for activating meningeal afferents via neuronal P2X receptors. Recently, we showed that ATP also increased degranulation of resident meningeal mast cells (Nurkhametova et al., 2019). However, the contribution of ATP-induced mast cell degranulation in aggravating the migraine pain remains unknown. Here we explored the role of meningeal mast cells in the pro-nociceptive effects of extracellular ATP. The impact of mast cells on ATP mediated activation of peripheral branches of trigeminal nerves was measured electrophysiologically in the dura mater of adult wild type (WT) or mast cell deficient mice. We found that a spontaneous spiking activity in the meningeal afferents, at baseline level, did not differ in two groups. However, in WT mice, meningeal application of ATP dramatically (24.6-fold) increased nociceptive firing, peaking at frequencies around 10 Hz. In contrast, in mast cell deficient animals, ATP-induced excitation was significantly weaker (3.5-fold). Application of serotonin to meninges in WT induced strong spiking. Moreover, in WT mice, the 5-HT3 antagonist MDL-7222 inhibited not only serotonin but also the ATP induced nociceptive firing. Our data suggest that extracellular ATP activates nociceptive firing in meningeal trigeminal afferents via amplified degranulation of resident mast cells in addition to direct excitatory action on the nerve terminals. This highlights the importance of mast cell degranulation via extracellular ATP, in aggravating the migraine pain.

Targets for improving dispatcher identification of acute stroke.

BACKGROUND: Accurate identification of acute stroke by Emergency Medical Dispatchers (EMD) is essential for timely and purposeful deployment of Emergency Medical Services (EMS), and a prerequisite for operating mobile stroke units. However, precision of EMD stroke recognition is currently modest. AIMS: We sought to identify targets for improving dispatcher stroke identification. METHODS: Dispatch codes and EMS patient records were cross-linked to investigate factors associated with an incorrect dispatch code in a prospective observational cohort of 625 patients with a final diagnosis of acute stroke or transient ischemic attack (TIA), transported to our stroke center as candidates for recanalization therapies. Call recordings were analyzed in a subgroup that received an incorrect low-priority dispatch code indicating a fall or unknown acute illness (n = 46). RESULTS: Out of 625 acute stroke/TIA patients, 450 received a high-priority stroke dispatch code (sensitivity 72.0%; 95% CI, 68.5-75.5). Independent predictors of dispatcher missed acute stroke included a bystander caller (aOR, 3.72; 1.48-9.34), confusion (aOR, 2.62; 1.59-4.31), fall at onset (aOR, 1.86; 1.24-2.78), and older age (aOR [per year], 1.02; 1.01-1.04). Of the analyzed call recordings, 71.7% revealed targets for improvement, including failure to recognize a Face Arm Speech Time (FAST) test symptom (21/46 cases, 18 with speech disturbance), or failure to thoroughly evaluate symptoms (12/46 cases). CONCLUSIONS: Based on our findings, efforts to improve dispatcher stroke identification should primarily focus on improving recognition of acute speech disturbance, and implementing screening of FAST-symptoms in emergency phone calls revealing a fall or confusion. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov . Unique identifier: NCT02145663.

Haptoglobin Hp1 Variant Does Not Associate with Small Vessel Disease.

Haptoglobin (Hp) is a plasma protein that binds free hemoglobin and protects tissues from oxidative damage. An Hp2 allele has been associated with an increased risk of cardiovascular complications. On the other hand, recent studies have suggested that Hp1 allele increases risk to develop severe cerebral small vessel disease. We aimed to replicate this finding in a first-ever stroke patient cohort. Hp was genotyped by PCR and gel electrophoresis in the Helsinki Stroke Aging Memory Study in patients with DNA and magnetic resonance imaging (MRI) available (SAM; n = 316). Lacunar infarcts and white matter lesions (WML) classified by Fazekas grading from brain MRI were associated with Hp genotypes. As population controls, we used participants of Cardiovascular diseases-a sub study of Health 2000 Survey (n = 1417). In the SAM cohort, 63.0% of Hp1-1 carriers (n = 46), 52.5% of Hp1-2 carriers (n = 141) and 51.2% of Hp2-2 carriers (n = 129) had severe WML (p = 0.372). There was no difference in severe WMLs between Hp1-1 vs. Hp1-2 and Hp2-2 carriers (p = 0.201). In addition, 68.9% of Hp1-1 carriers (n = 45), 58.5% of Hp1-2 carriers (n = 135), and 61.8% of Hp2-2 carriers (n = 126) had one or more lacunar lesions (p = 0.472). There was no difference in the number of patients with at least one lacunar infarct between Hp1-1 vs. Hp1-2 and Hp2-2 groups (p = 0.322). Neither was there any difference when diabetic patients (type I and II) were examined separately. Hp1 allele is not associated with an increased risk for cerebral small vessel disease in a well-characterized Finnish stroke patient cohort.

Diagnosing cerebral ischemia with door-to-thrombolysis times below 20 minutes.

OBJECTIVES: To clarify diagnostic accuracy and consequences of misdiagnosis in the admission evaluation of stroke-code patients in a neurologic emergency department with less than 20-minute door-to-thrombolysis times. METHODS: Accuracy of admission diagnostics was studied in an observational cohort of 1,015 stroke-code patients arriving by ambulance as candidates for recanalization therapy between May 2013 and November 2015. Immediate admission evaluation was performed by a stroke neurologist or a neurology resident with dedicated stroke training, primarily utilizing CT-based imaging. RESULTS: The rate of correct admission diagnosis was 91.1% (604/663) for acute cerebral ischemia (ischemic stroke/TIA), 99.2% (117/118) for hemorrhagic stroke, and 61.5% (144/234) for stroke mimics. Of the 150 (14.8%) misdiagnosed patients, 135 (90.0%) had no acute findings on initial imaging and 100 (67.6%) presented with NIH Stroke Scale score 0 to 2. Misdiagnosis altered medical management in 70 cases, including administration of unnecessary treatments (thrombolysis n = 13, other n = 24), omission of thrombolysis (n = 5), delays to specific treatments of stroke mimics (n = 13, median 56 [31-93] hours), and delays to antiplatelet medication (n = 14, median 1 [1-2] day). Misdiagnosis extended emergency department stay (median 6.6 [4.7-10.4] vs 5.8 [3.7-9.2] hours; p = 0.001) and led to unnecessary stroke unit stay (n = 10). Detailed review revealed 8 cases (0.8%) in which misdiagnosis was possible or likely to have worsened outcomes, but no death occurred as a result of misdiagnosis. CONCLUSIONS: Our findings support the safety of highly optimized door-to-needle times, built on thorough training in a large-volume, centralized stroke service with long-standing experience. Augmented imaging and front-loaded specialist engagement are warranted to further improve rapid stroke diagnostics.