Consistencies and Differences in Intermediate Physiological Phenotypes of Vascular Ageing between Ischaemic Stroke Aetiologies.

OBJECTIVE: Arterial stiffness, cerebral pulsatility, and beat-to-beat blood pressure variability partly mediate the relationship between hypertension and stroke, but it is unknown if these intermediate phenotypes of vascular ageing differ between stroke aetiologies. We therefore aimed to characterize differences in these intermediate cardiovascular phenotypes between patients presenting with strokes of different aetiologies. METHODS: In consecutive patients on best medical management 1 month after TIA or nondisabling stroke (Oxford Vascular Study), arterial stiffness (PWV) was measured by applanation tonometry (Sphygmocor), middle cerebral blood flow velocity, and pulsatility index (MCA-PI) were measured by transcranial ultrasound (TCD, DWL Doppler Box), and beat-to-beat BP variability was measured with a Finometer. Differences between patients with large artery (LAS), small vessel (SVD), cardioembolic (CE), or undetermined events were derived, including adjustment for cardiovascular risk factors. Relationships were characterized by mixed linear models. RESULTS: In 909 eligible patients, MCA-PI, PWV, and SBPV were all positively skewed. Mean values were greatest in LAS than CE and lowest in SVD (p < 0.001). However, after adjustment for age, sex, and risk factors, PI was greatest in LAS and lowest in CE stroke, whilst PWV was greatest in SVD and undetermined stroke (p < 0.001). In multivariate linear models, age was more strongly associated with PWV and PI in patients with small vessel stroke than other aetiologies, particularly under the age of 65, but SBPV was only weakly associated with demographic indices in all stroke subtypes. CONCLUSIONS: Intermediate cardiovascular phenotypes of vascular ageing had similar demographic associations between stroke aetiologies, but these were particularly strong in patients with small vessel stroke under the age of 65, implying a potential role of these phenotypes in increasing stroke risk in this patient group.

Aortic Stiffness, Pulse Pressure, and Cerebral Pulsatility Progress Despite Best Medical Management: The OXVASC Cohort.

BACKGROUND: Increased cerebral arterial pulsatility is associated with cerebral small vessel disease, recurrent stroke, and dementia despite the best medical treatment. However, no study has identified the rates and determinants of progression of arterial stiffness and pulsatility. METHODS: In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (OXVASC [Oxford Vascular Study]), arterial stiffness (pulse wave velocity [PWV]) and aortic systolic, aortic diastolic, and aortic pulse pressures (aoPP) were measured by applanation tonometry (Sphygmocor), while middle cerebral artery (MCA) peak (MCA-PSV) and trough (MCA-EDV) flow velocity and Gosling pulsatility index (PI; MCA-PI) were measured by transcranial ultrasound (transcranial Doppler, DWL Doppler Box). Repeat assessments were performed at the 5-year follow-up visit after intensive medical treatment and agreement determined by intraclass correlation coefficients. Rates of progression and their determinants, stratified by age and sex, were determined by mixed-effects linear models, adjusted for age, sex, and cardiovascular risk factors. RESULTS: In 188 surviving, eligible patients with repeat assessments after a median of 5.8 years. PWV, aoPP, and MCA-PI were highly reproducible (intraclass correlation coefficients, 0.71, 0.59, and 0.65, respectively), with progression of PWV (2.4%; P<0.0001) and aoPP (3.5%; P<0.0001) but not significantly for MCA-PI overall (0.93; P=0.22). However, PWV increased at a faster rate with increasing age (0.009 m/s per y/y; P<0.0001), while aoPP and MCA-PI increased significantly above the age of 55 years (aoPP, P<0.0001; MCA-PI, P=0.009). Higher aortic systolic blood pressure and diastolic blood pressure predicted a greater rate of progression of PWV and aoPP, but not MCA-PI, although current MCA-PI was particularly strongly associated with concurrent aoPP (P<0.001). CONCLUSIONS: Arterial pulsatility and aortic stiffness progressed significantly after 55 years of age despite the best medical treatment. Progression of stiffness and aoPP was determined by high blood pressure, but MCA-PI predominantly reflected current aoPP. Treatments targetting cerebral pulsatility may need to principally target aortic stiffness and pulse pressure to have the potential to prevent cerebral small vessel disease.

Body Mass Index and Arterial Stiffness Are Associated With Greater Beat-to-Beat Blood Pressure Variability After Transient Ischemic Attack or Minor Stroke.

[Figure: see text].

Transcriptional programming of lipid and amino acid metabolism by the skeletal muscle circadian clock.

Circadian clocks are fundamental physiological regulators of energy homeostasis, but direct transcriptional targets of the muscle clock machinery are unknown. To understand how the muscle clock directs rhythmic metabolism, we determined genome-wide binding of the master clock regulators brain and muscle ARNT-like protein 1 (BMAL1) and REV-ERBα in murine muscles. Integrating occupancy with 24-hr gene expression and metabolomics after muscle-specific loss of BMAL1 and REV-ERBα, here we unravel novel molecular mechanisms connecting muscle clock function to daily cycles of lipid and protein metabolism. Validating BMAL1 and REV-ERBα targets using luciferase assays and in vivo rescue, we demonstrate how a major role of the muscle clock is to promote diurnal cycles of neutral lipid storage while coordinately inhibiting lipid and protein catabolism prior to awakening. This occurs by BMAL1-dependent activation of Dgat2 and REV-ERBα-dependent repression of major targets involved in lipid metabolism and protein turnover (MuRF-1, Atrogin-1). Accordingly, muscle-specific loss of BMAL1 is associated with metabolic inefficiency, impaired muscle triglyceride biosynthesis, and accumulation of bioactive lipids and amino acids. Taken together, our data provide a comprehensive overview of how genomic binding of BMAL1 and REV-ERBα is related to temporal changes in gene expression and metabolite fluctuations.

Increasing Blood Pressure Variability Predicts Poor Functional Outcome Following Acute Stroke.

INTRODUCTION: Increasing blood pressure variability has been reported following acute stroke, but there is uncertainty about how best to measure it and about the impact on prognosis following acute ischaemic stroke and transient ischaemic attack. METHODS: Enhanced casual blood pressure and ambulatory blood pressure monitoring were completed at baseline (≤48 h post symptom onset). Blood pressure variability was defined by standard deviation and coefficient of variation of systolic, diastolic, mean arterial pressure, and pulse pressure. Modified Rankin scale score ≥3 described poor functional outcome assessed at 1- and 12-months post-stroke. Multivariable logistic regression models incorporating blood pressure variability measurement and other factors were performed, and odds ratio and 95% confidence intervals reported. RESULTS: 232 patients were recruited; 45 were dependent at 1-month, and 37 at 12-months. Dependent patients were more likely to be older, with a higher burden of pre-morbid conditions, and with increased blood pressure variability. Enhanced casual standard deviations of diastolic blood pressure [1.19 (1.02 to 1.39)] and mean arterial pressure [1.20 (1.00 to 1.43)] predicted dependency at 1-month. Predictors of 12-month dependency included: enhanced casual standard deviation of mean arterial pressure [1.21 (1.0-1.46)]; 24 h ambulatory monitor standard deviations of diastolic blood pressure [2.30 (1.08-4.90)] and mean arterial pressure [1.72 (1.09-2.72)], and the coefficient of variation of mean arterial pressure [1.76 (1.05-2.94)]; day-time ambulatory monitor coefficient of variation of systolic blood pressure [1.44 (1.02-2.03)] and mean arterial pressure [1.46 (1.02-2.08)]; and night-time ambulatory standard deviation of diastolic blood pressure [1.65 (1.03 -2.63)], and the coefficient of variation of mean arterial pressure and [1.38 (1.00- 1.90)] and pulse pressure [1.29 (1.00-1.65)]. CONCLUSION: Increasing blood pressure variability is independently and modestly associated with poor functional outcome at 1- and 12-months following acute stroke.

Confounding of Cerebral Blood Flow Velocity by Blood Pressure During Breath Holding or Hyperventilation in Transient Ischemic Attack or Stroke.

Background and Purpose- Breath holding (BH) and hyperventilation are used to assess abnormal cerebrovascular reactivity, often in relation to severity of small vessel disease and risk of stroke with carotid stenosis, but responses may be confounded by blood pressure (BP) changes. We compared effects of BP and end-tidal carbon dioxide (etCO2) on middle cerebral artery mean flow velocity (MFV) in consecutive transient ischemic attack and minor stroke patients. Methods- In the population-based, prospective OXVASC (Oxford Vascular Study) phenotyped cohort, change in MFV on transcranial Doppler ultrasound (ΔMFV, DWL-DopplerBox), beat-to-beat BP (Finometer), and etCO2 was measured during 30 seconds of BH or hyperventilation. Two blinded reviewers independently assessed recording quality. Dependence of ΔMFV on ΔBP and ΔetCO2 was determined by general linear models, stratified by quartiles. Results- Four hundred eighty-eight of 602 (81%) patients with adequate bone windows had high-quality recordings, more often in younger participants (64.6 versus 68.7 years; P<0.01), whereas 426 had hyperventilation tests (70.7%). During BH, ΔMFV was correlated with a rise in mean blood pressure (MBP; r2=0.15, P<0.001) but not ΔCO2 (r2=0.002, P=0.32), except in patients with ΔMBP <10% (r2=0.13, P<0.001). In contrast during hyperventilation, the fall in MFV was similarly correlated with reduction in CO2 and reduction in MBP (ΔCO2: r2=0.13, P<0.001; ΔMBP: r2=0.12, P<0.001), with a slightly greater effect of ΔCO2 when ΔMBP was <10% (r2=0.15). Stratifying by quartile, MFV increased linearly during BH across quartiles of ΔMBP, with no increase with ΔetCO2. In contrast, during hyperventilation, MFV decreased linearly with ΔetCO2, independent of ΔMBP. Conclusions- In older patients with recent transient ischemic attack or minor stroke, cerebral blood flow responses to BH were confounded by BP changes but reflected etCO2 change during hyperventilation. Correct interpretation of cerebrovascular reactivity responses to etCO2, including in small vessel disease and carotid stenosis, requires concurrent BP measurement.

Prognostic Significance of Blood Pressure Variability on Beat-to-Beat Monitoring After Transient Ischemic Attack and Stroke.

BACKGROUND AND PURPOSE: Visit-to-visit and day-to-day blood pressure (BP) variability (BPV) predict an increased risk of cardiovascular events but only reflect 1 form of BPV. Beat-to-beat BPV can be rapidly assessed and might also be predictive. METHODS: In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (Oxford Vascular Study), BPV (coefficient of variation) was measured beat-to-beat for 5 minutes (Finometer), day-to-day for 1 week on home monitoring (3 readings, 3× daily), and on awake ambulatory BP monitoring. BPV after 1-month standard treatment was related (Cox proportional hazards) to recurrent stroke and cardiovascular events for 2 to 5 years, adjusted for mean systolic BP. RESULTS: Among 520 patients, 26 had inadequate beat-to-beat recordings, and 22 patients were in atrial fibrillation. Four hundred five patients had all forms of monitoring. Beat-to-beat BPV predicted recurrent stroke and cardiovascular events independently of mean systolic BP (hazard ratio per group SD, stroke: 1.47 [1.12-1.91]; P=0.005; cardiovascular events: 1.41 [1.08-1.83]; P=0.01), including after adjustment for age and sex (stroke: 1.47 [1.12-1.92]; P=0.005) and all risk factors (1.40 [1.00-1.94]; P=0.047). Day-to-day BPV was less strongly associated with stroke (adjusted hazard ratio, 1.29 [0.97-1.71]; P=0.08) but similarly with cardiovascular events (1.41 [1.09-1.83]; P=0.009). BPV on awake ambulatory BP monitoring was nonpredictive (stroke: 0.89 [0.59-1.35]; P=0.59; cardiovascular events: 1.08 [0.77-1.52]; P=0.65). Despite a weak correlation (r=0.119; P=0.02), beat-to-beat BPV was associated with risk of recurrent stroke independently of day-to-day BPV (1.41 [1.05-1.90]; P=0.02). CONCLUSIONS: Beat-to-beat BPV predicted recurrent stroke and cardiovascular events, independently of mean systolic BP and risk factors but short-term BPV on ambulatory BP monitoring did not. Beat-to-beat BPV may be a useful additional marker of cardiovascular risk.

Correlations between gene expression highlight a different activation of ACE/TLR4/PTGS2 signaling in symptomatic and asymptomatic plaques in atherosclerotic patients.

Inflammation has a key role and translates the effects of many known risk factors for the disease in atherosclerotic vulnerable plaques. Aiming to look into the elements that induce the development of either a vulnerable or stable atherosclerotic plaque, and considering that inflammation has a central role in the progression of lesions, we analyzed the expression of genes involved in the ACE/TLR4/PTGS2 signaling in carotid plaques of symptomatic and asymptomatic patients. Patients with internal carotid artery stenosis undergoing carotid endarterectomy at Verona University Hospital were included in this study. A total of 71 patients was considered for gene expression analysis (29 atherothrombotic stroke patients and 42 asymptomatic patients). Total RNA was extracted from the excised plaques and expression of PTGS2, ACE, TLR4, PTGER4, PTGER3, EPRAP and ACSL4 genes was analyzed by real-time PCR. The correlation between the pair of genes was studied by Spearman coefficient. From the analyzed genes, we did not observe any individual difference in gene expression but the network of co-expressed genes suggests a different activation of pathways in the two groups of plaques.

White Matter Imaging Correlates of Early Cognitive Impairment Detected by the Montreal Cognitive Assessment After Transient Ischemic Attack and Minor Stroke.

BACKGROUND AND PURPOSE: Among screening tools for cognitive impairment in large cohorts, the Montreal Cognitive Assessment (MoCA) seems to be more sensitive to early cognitive impairment than the Mini-Mental State Examination (MMSE), particularly after transient ischemic attack or minor stroke. We reasoned that if MoCA-detected early cognitive impairment is pathologically significant, then it should be specifically associated with the presence of white matter hyperintensities (WMHs) and reduced fractional anisotropy (FA) on magnetic resonance imaging. METHODS: Consecutive eligible patients with transient ischemic attack or minor stroke (Oxford Vascular Study) underwent magnetic resonance imaging and cognitive assessment. We correlated MoCA and MMSE scores with WMH and FA, then specifically studied patients with low MoCA and normal MMSE. RESULTS: Among 400 patients, MoCA and MMSE scores were significantly correlated (all P<0.001) with WMH volumes (rMoCA=-0.336; rMMSE=-0.297) and FA (rMoCA=0.409; rMMSE=0.369) and-on voxel-wise analyses-with WMH in frontal white matter and reduced FA in almost all white matter tracts. However, only the MoCA was independently correlated with WMH volumes (r=-0.183; P<0.001), average FA values (r=0.218; P<0.001), and voxel-wise reduced FA in anterior tracts after controlling for the MMSE. In addition, patients with low MoCA but normal MMSE (n=57) had higher WMH volumes (t=3.1; P=0.002), lower average FA (t=-4.0; P<0.001), and lower voxel-wise FA in almost all white matter tracts than those with normal MoCA and MMSE (n=238). CONCLUSIONS: In patients with transient ischemic attack or minor stroke, early cognitive impairment detected with the MoCA but not with the MMSE was independently associated with white matter damage on magnetic resonance imaging, particularly reduced FA.

Time-of-Day Could Affect Cognitive Screening Performance in Older Patients with TIA and Stroke.

BACKGROUND AND PURPOSE: The impact of time-of-day on the cognitive performance of older patients with limited cognitive reserve after a transient ischemic attack (TIA) or stroke, and on short cognitive tests, such as the Montreal Cognitive Assessment (MoCA), is unknown. We retrospectively studied whether morning versus afternoon assessment might affect the classification of patients aged 70 or older as severe (SCI), mild (MCI), and no (NCI) cognitive impairment by the MoCA. METHODS: Morning (12 p.m. or earlier) versus afternoon (later than 12 p.m.) proportions of SCI (MoCA score <20), MCI (MoCA score 25-20) and NCI (MoCA score ≥26) were compared in a cohort of patients aged ≥70, attending a rapid-access TIA/stroke clinic. RESULTS: Of 278 patients, 113 (40.6%) were tested in the morning and 165 (59.4%) in the afternoon. The proportion with SCI was greater in the afternoon than in the morning (10.9 vs. 1.8%, respectively, p = 0.004), with no difference in age, education, diagnosis, disability, or vascular risk factors. CONCLUSIONS: Time-of-day appears to affect cognitive performance of older patients after they undergo TIA and minor stroke. If our cross-sectional findings are confirmed in cross-over studies with repeated testing, timing of assessments should be considered in clinical practice and in research studies.

Clinical outcomes of secondary prevention strategies for young patients with cryptogenic stroke and patent foramen ovale.

Background The aim of this study was to compare the immediate and long-term clinical outcomes of medical therapy and percutaneous patent foramen ovale (PFO) closure as secondary prevention strategies in patients younger than 55 years of age presenting with cryptogenic stroke and PFO. Methods Between January 2006 and April 2015, all patients with the diagnosis of cryptogenic stroke and PFO were analysed and prospectively followed. Stroke was confirmed in 159 out of 309 patients (51%). In the remaining cases, other neurological conditions were found and therefore excluded from further analysis. Patients received PFO closure or medical therapy on the basis of a pre-specified algorithm. Primary outcome was the assessment of recurrent ischaemic events at follow-up. Results Percutaneous PFO closure was performed in 77 patients (48%) and 82 (52%) were treated medically. Mean follow-up was 51.6 ± 34.8 months. Two ischaemic strokes occurred in the medical group only (2.4% vs 0%; P = 0.16) and no complications related to the invasive procedure were observed. Conclusions The diagnosis of stroke in patients with PFO could be confirmed in 50% of cases only, underlining the importance of a multidisciplinary evaluation of these patients. A very low ischaemic recurrence rate was observed in the medical therapy group, suggesting that a personalized treatment based on a prespecified diagnostic algorithm yields good clinical results irrespective of the treatment modality. Given the low number of recurrences, larger cohorts may be needed to prove significant differences.

Omega-3 fatty acids and protein metabolism: enhancement of anabolic interventions for sarcopenia.

PURPOSE OF REVIEW: The increased age observed in most countries, with the associated higher rates of chronic illnesses and cancer, and a diffuse sedentary lifestyle, will increase the number of patients with clinically relevant anabolic resistance, sarcopenia and its complications. The need for solutions to this major health issue is, therefore, pressing. RECENT FINDINGS: The metabolic derangements and other consequences associated with sarcopenia can be slowed or even prevented by specific nutritional interventions. New evidence is available about the efficacy of omega-3 fatty acid dietary supplementation to improve protein metabolism and counteract anabolic resistance through indirect effects. Studies show that the anabolic stimuli from substrates (e.g. amino acids or proteins), hormones (e.g. insulin) and/or physical activity in skeletal muscle can be enhanced by long-term fish oil administration. SUMMARY: The review of data from recent studies on this topic suggests that dietary omega-3 fatty acid supplementation, in association with an anabolic stimulus, could potentially provide a safe, simple and low-cost intervention to counteract anabolic resistance and sarcopenia. This intervention may contribute to prevent cachexia and disabilities. Supplementation should be given in the earlier stages of sarcopenia (e.g. precachexia). Further research should, however, be performed to better understand the mechanisms involved and the best dosage and timing of administration.

Cyclooxygenase 2, toll-like receptor 4 and interleukin 1ß mRNA expression in atherosclerotic plaques of type 2 diabetic patients.

OBJECTIVES AND DESIGN: Inflammation has a prominent role in the development of atherosclerosis. Type 2 diabetes could contribute to atherosclerosis development by promoting inflammation. This status might accelerate changes in intrinsic vascular wall cells and favor plaque formation. Cyclooxygenase 2 (COX-2) is highly expressed in atherosclerotic plaques. COX-2 gene expression is promoted through activation of toll-like receptor 4 (TLR4) and pro-inflammatory cytokine interleukin 1ß (IL1-ß). Aim of this study is to investigate whether expression profiles of pro-inflammatory genes such as COX-2, TLR4 and IL1-ß in atherosclerotic plaques are altered in type 2 diabetes (T2D). METHODS: Total RNA was isolated from plaques of atherosclerotic patients and expression of COX-2, TLR4, IL1-ß analyzed using real-time PCR. Histological analysis was performed on sections of the plaque to establish the degree of instability. RESULTS: Statistically significant differences in mRNA expression of COX-2 and IL1-ß were found in plaques of T2D compared with non-T2D patients. A multi-variable linear regression model suggests that COX-2 mRNA expression is affected by T2D pathology and IL1-ß mRNA expression in atherosclerotic plaques. CONCLUSIONS: Our results support the hypothesis that T2D pathology contributes in vivo to increase the inflammatory process associated with the atherosclerotic plaque formation, as shown by an increment of COX-2 and IL1-ß mRNA expression.

Improving post-stroke dysphagia outcomes through a standardized and multidisciplinary protocol: an exploratory cohort study.

Stroke is a major cause of dysphagia. Few studies to date have reported on standardized multidisciplinary protocolized approaches to the management of post-stroke dysphagia. The aim of this retrospective cohort study was to evaluate the impact of a standardized multidisciplinary protocol on clinical outcomes in patients with post-stroke dysphagia. We performed retrospective chart reviews of patients with post-stroke dysphagia admitted to the neurological ward of Verona University Hospital from 2004 to 2008. Outcomes after usual treatment for dysphagia (T- group) were compared versus outcomes after treatment under a standardized diagnostic and rehabilitative multidisciplinary protocol (T+ group). Outcome measures were death, pneumonia on X-ray, need for respiratory support, and proportion of patients on tube feeding at discharge. Of the 378 patients admitted with stroke, 84 had dysphagia and were enrolled in the study. A significantly lower risk of in-hospital death (odds ratio [OR] 0.20 [0.53-0.78]), pneumonia (OR 0.33 [0.10-1.03]), need for respiratory support (OR 0.48 [0.14-1.66]), and tube feeding at discharge (OR 0.30 [0.09-0.91]) was recorded for the T+ group (N = 39) as compared to the T- group (N = 45). The adjusted OR showed no difference between the two groups for in-hospital death and tube feeding at discharge. Use of a standardized multidisciplinary protocolized approach to the management of post-stroke dysphagia may significantly reduce rates of aspiration pneumonia, in-hospital mortality, and tube feeding in dysphagic stroke survivors. Consistent with the study's exploratory purposes, our findings suggest that the multidisciplinary protocol applied in this study offers an effective model of management of post-stroke dysphagia.

Age-specific sex-differences in cerebral blood flow velocity in relation to haemoglobin levels.

INTRODUCTION: Cerebral blood flow (CBF) declines with age and abnormalities in CBF are associated with age-related cerebrovascular disease and neurodegeneration. Women have higher CBF than men, although this sex-difference diminishes to some extent with age in healthy subjects. The physiological drivers of these age/sex differences are uncertain, but might be secondary to age and sex-differences in haemoglobin (Hb) level. Hb levels are inversely correlated with CBF, are lower in women, and decline with age in men, but the interrelations between these factors have not been explored systematically either in healthy subjects or across the full age-range in patients with vascular risk factors. We aimed to determine the age-specific interrelations between sex, Hb, and CBF velocity in a large cohort of patients with cerebrovascular disease. PATIENTS AND METHODS: In patients with a recent transient ischaemic attack or minor stroke (Oxford Vascular Study) and no ipsilateral or contralateral stenosis of the carotid or intracranial arteries, we related peak-systolic velocity (PSV) and other parameters on transcranial Doppler ultrasound (TCD) of the middle cerebral artery to sex, age, Hb and vascular risk factors. RESULTS: Of 958 eligible subjects (mean age/SD = 68.04/14.26, 53.2% male), younger women (age < 55 years) had higher CBF velocities than men (mean sex difference in PSV at age < 55 years = 16.31 cm/s; p < 0.001), but this difference declined with age (interaction p < 0.001), such that it was no longer significant at age 75-84 (∆PSV = 3.26 cm/s; p = 0.12) and was reversed at age ⩾ 85 (∆PSV = -7.42 cm/s; p = 0.05). These changes mirrored trends in levels of Hb, which were higher in men at age < 55 (∆Hb = 1.92 g/dL; p < 0.001), but steadily decreased with age in men but not in women (interaction p < 0.001), with no residual sex-difference at age ⩾ 85 (∆Hb = 0.12 g/dL; p = 0.70). There was an inverse correlation between Hb and PSV in both women and men (both p ⩽ 0.01), and the sex-difference in PSV at age < 55 was substantially diminished after adjustment for Hb (∆PSV = 6.92; p = 0.036; ∆PSV = 5.92, p = 0.13 with further adjustment for end-tidal CO2). In contrast, the sex difference in PSV was unaffected by adjustment for systolic and diastolic blood pressure, heart rate, and vascular risk factors (history of hypertension, diabetes, hyperlipidaemia and smoking). DISCUSSION: CBF velocity is strongly correlated with Hb level at all ages, and sex-differences in CBF velocity appear to be explained in major part by age-related sex-differences in Hb.

Patent Foramen Ovale Closure in Older Patients With Stroke: Patient Selection for Trial Feasibility.

BACKGROUND AND OBJECTIVES: Whether patent foramen ovale (PFO) closure benefits older patients with PFO and cryptogenic stroke is unknown because randomized controlled trials (RCTs) have predominantly enrolled patients younger than 60 years of age. Our objective was to estimate anticipated effects of PFO closure in older patients to predict the numbers needed to plan an RCT. METHODS: Effectiveness estimates are derived from major observational studies (Risk of Paradoxical Embolism [RoPE] Study and Oxford Vascular Study, together referred to as the "RoPE-Ox" database) and all 6 major RCTs (Systematic, Collaborative, PFO Closure Evaluation [SCOPE] Consortium). To estimate stroke recurrence risk, observed outcomes were calculated for patients older than 60 years in the age-inclusive observational databases (n = 549). To estimate the reduction in the rate of recurrent stroke associated with PFO closure vs medical therapy based on the RoPE score and the presence of high-risk PFO features, a Cox proportional hazards regression model was developed on the RCT data in the SCOPE database (n = 3,740). These estimates were used to calculate sample sizes required for a future RCT. RESULTS: Five-year risk of stroke recurrence using Kaplan-Meier estimates was 13.7 (95% CI 10.5-17.9) overall, 14.9% (95% CI 10.2-21.6) in those with high-risk PFO features. Predicted relative reduction in the event rate with PFO closure was 12.9% overall, 48.8% in those with a high-risk PFO feature. Using these estimates, enrolling all older patients with cryptogenic stroke and PFO would require much larger samples than those used for prior PFO closure trials, but selectively enrolling patients with high-risk PFO features would require totals of 630 patients for 90% power and 471 patients for 80% power, with an average of 5 years of follow-up. DISCUSSION: Based on our projections, anticipated effect sizes in older patients with high-risk features make a trial in these subjects feasible. With lengthening life expectancy in almost all regions of the world, the utility of PFO closure in older adults is increasingly important to explore.

Polymorphism -2604G>A variants in TLR4 promoter are associated with different gene expression level in peripheral blood of atherosclerotic patients.

Toll-like receptor-4 (TLR4) is a primary receptor of the innate immune reaction and compelling evidence demonstrates its involvement in the pathogenesis of atherosclerosis and stroke. TLR4 is constitutively expressed on monocytes and endothelial cells; it is highly expressed in atherosclerotic plaques and in peripheral blood of patients after ischemic stroke. Polymorphisms in the promoter region that alter the transcriptional regulation of this gene may represent genetic risk factors involved in the predisposition to atherosclerotic disease. In this study we investigated the effect on TLR4 gene expression of three polymorphisms in the upstream regulatory region at positions -1607T>C/rs10759932, -2026A>G/rs1927914 and -2604G>A/rs10759931 in peripheral blood of atherosclerotic patients. RNA from individuals homozygous for the -2604A allele showed a lower expression of the gene when compared to patients carrying the counterparts GG+GA. Electrophoretic mobility shift assays showed differences in the electrophoretic mobility of the DNA-nuclear protein complexes formed by the G>A variants, suggesting that the two alleles differ in their binding affinity to transcriptional factors.

What is still missing in acute-phase treatment of stroke: a prospective observational study.

Early recognition of stroke symptoms and activation of emergency medical service (EMS) positively affects prognosis after a stroke. To assess stroke awareness among stroke patients and medical personnel in the catchment area of Verona Hospital and how it affects stroke care, we prospectively studied timing of acute stroke care in relation to patients' characteristics. Patients admitted to Medical Departments of Verona University Hospital between January 1st and December 31st 2009 with a diagnosis of TIA or stroke were enrolled. Outcome measures were: time between (i) symptoms onset and hospital arrival, (ii) hospital arrival and brain CT scan, blood examination, ECG and neurological evaluation. The following patient/event characteristics were also collected: means of hospital arrival, sex, age, degree of disability, type of event (first or recurrent) and acute-phase treatment. Of 578 patients providing complete information, 60 % arrived to the emergency department with the EMS (EMS+ group), while 40 % arrived on their own (EMS-). EMS+ group was older than EMS- (mean age 76.2, SD 13.2, vs. 72.3, SD 13, respectively), displayed more severe symptoms (mRS 4 vs. 2) and shorter time interval between symptoms onset and hospital arrival, hospital arrival and CT scan, ECG, laboratory tests and neurological evaluation (p < 0.0001); 22 % of the EMS+ patients were stroke recurrences versus 29 % of the EMS- (p = 0.058); 85 % of thrombolised patients were EMS+. We conclude that there is a lack of awareness of stroke symptoms and risks of recurrence even among patients who already had a stroke and among medical personnel.

Reduced Left Atrial Rotational Flow Is Independently Associated With Embolic Brain Infarcts.

BACKGROUND: Up to 25% of embolic strokes occur in individuals without atrial fibrillation (AF) or other identifiable mechanisms. OBJECTIVES: This study aims to assess whether left atrial (LA) blood flow characteristics are associated with embolic brain infarcts, independently of AF. METHODS: The authors recruited 134 patients: 44 with a history of ischemic stroke and 90 with no history of stroke but CHA2DS2VASc score ≥1. Cardiac magnetic resonance (CMR) evaluated cardiac function and LA 4-dimensional flow parameters, including velocity and vorticity (a measure of rotational flow), and brain magnetic resonance imaging (MRI) was performed to detect large noncortical or cortical infarcts (LNCCIs) (likely embolic), or nonembolic lacunar infarcts. RESULTS: Patients (41% female; age 70 ± 9 years) had moderate stroke risk (median CHA2DS2VASc = 3, Q1-Q3: 2-4). Sixty-eight (51%) had diagnosed AF, of whom 58 (43%) were in AF during CMR. Thirty-nine (29%) had ≥1 LNCCI, 20 (15%) had ≥1 lacunar infarct without LNCCI, and 75 (56%) had no infarct. Lower LA vorticity was significantly associated with prevalent LNCCIs after adjustment for AF during CMR, history of AF, CHA2DS2VASc score, LA emptying fraction, LA indexed maximum volume, left ventricular ejection fraction, and indexed left ventricular mass (OR: 2.06 [95% CI: 1.08-3.92 per SD]; P = 0.027). By contrast, LA flow peak velocity was not significantly associated with LNCCIs (P = 0.21). No LA parameter was associated with lacunar infarcts (all P > 0.05). CONCLUSIONS: Reduced LA flow vorticity is significantly and independently associated with embolic brain infarcts. Imaging LA flow characteristics may aid identification of individuals who would benefit from anticoagulation for embolic stroke prevention, regardless of heart rhythm.