Carotid Artery Velocity Research Articles

Morphological and Hemodynamic Features of the Carotid Artery on Color Doppler Ultrasound in Hypertensive Patients

Objective: 1. Described the characteristics and morphology of the carotid artery on color Doppler ultrasonography in patients with hypertensive. 2. Determine the relationship between carotid intima-media thickness (cIMT) on color Doppler ultrasound images and some clinical and laboratory parameters and some risk factors in hypertensive patients. Subjects and methods: This was a cross-sectional descriptive study on 64 hospitalized hypertensive patients. Results: 62.5% are female. Mean age 66.41±11.91. The right common cIMT 0.74 (0.7-0.81) mm; the left was 0.8 (0.7-0.8) mm; the average cIMT on both sides was 0.75 (0.75-0.79) mm. Mean peak systolic velocity of the right common carotid artery 58.03±14.74 cm/s; left side 60.71±15.73 cm/s. Right common carotid end-diastolic velocity 14.68±4.88 cm/s; left side 16.09±6.04 cm/s. Right common carotid resistance index 0.75±0.063; left side 0.74±0.067. There were 25 (39.1%) cases of right common carotid atherosclerotic plaque with the thickest 2.500.71mm and 33 (51.6%) cases of left common carotid plaque with the thickest 2.3 (1.99-2)mm. There were an independent correlation between age and sex with the cIMT on both sides with correlation coefficients of R=0.514, p=0.013; R=0.514, p < 0.0001, respectively. Conclusion: There were a correlation between the common cIMT with age and sex, every 1 year increase will increase the thickness of the common cIMT by 0.005 mm. cIMT was higher than in men.

Shear wave elastography to evaluate the effect of serum uric acid levels on carotid artery elasticity in patients with high-normal blood pressure

Background: Populations with normal high blood pressure often already have elevated blood uric acid levels and a higher chance of developing atherosclerosis, which accelerates the process of cardiovascular disease. The risk of atherosclerosis increases with thickening of the carotid artery intima-media, and changes in carotid artery elasticity precede intima-media changes, so early monitoring of carotid artery elasticity is of great significance in the prevention of cardiovascular disease. Using shear wave elastography (SWE) to evaluate the effect of serum uric acid (SUA) levels on carotid artery elasticity in patients with high-normal blood pressure (BP). Methods: One hundred and fifteen patients with high-normal BP were selected, and then divided into tertiles according to the SUA levels. The left carotid intima-media thickness (IMT), peak systolic velocity (PSV) and diameter of common carotid artery were measured by two-dimensional ultrasound and Doppler flow imaging. Longitudinal elasticity of the left anterior carotid wall was measured by SWE, including the mean values of the minimum elastic modulus (MEmin), maximum elastic modulus (MEmax) and mean elastic modulus (MEmean). Results: IMT, MEmean, MEmin and MEmax were obviously higher in the 3rd tertile (all P < 0.05), while there were no obviously different between the 1st tertile and 2nd tertile. Pearson correlation analysis showed positive correlations between SUA and SWE-related parameters, while there was no correlation with IMT. Multiple linear regression analysis found that age, systolic BP, and SUA levels were independently associated with SWE-related parameters. Conclusion: SWE will be more helpful than IMT in monitoring the effect of blood uric acid levels on carotid artery elasticity in patients with high-normal BP.

Comparing Carotid Artery Velocities with Current ASCVD Risk Stratification: A Novel Approach to Simpler Risk Assessment

PurposeTo explore the potential of a novel approach to simplify risk assessment by comparing carotid artery velocities with current atherosclerotic cardiovascular disease (ASCVD) risk stratification method using nonlinear measurements.MethodsIn this prospective study conducted at a medical center in southern Taiwan from January 1, 2020, to December 31, 2021, 1636 participants aged 40–75 years without prior ASCVD events were enrolled. Carotid flow velocity was obtained through duplex ultrasonography. ASCVD risk was categorized into two groups according to the 2022 USPSTF guidelines for primary prevention. We analyzed associations between flow indices and ASCVD risk using logistic regression and generalized additive models (GAMs).ResultsThe end diastolic velocity (EDV) of common carotid artery (CCA) and the peak systolic velocity (PSV) of internal carotid artery (ICA) were inversely and nonlinearly associated with cardiovascular event risk. Multivariate logistic regression analysis with ROC curves revealed that the optimal speed for the EDV of CCA was approximately 23.75 cm/s, and the optimal PSV and EDV of ICA were approximately 81.75 cm/s and 26.75 cm/s, respectively. The GAMs showed U-shaped relationships between elevated ASCVD risk and blood flow velocity in the carotid arteries, with inflection points of approximately 82 cm/s in the PSV of ICA and near 25 cm/s in the EDV of CCA. Both methods revealed similar results.ConclusionsThe EDVs and PSVs of the CCA and ICA are associated with the development of cardiovascular events. Optimal velocity ranges were identified; however, further hemodynamic investigations are warranted.

Ultrasonographic Predictors for Post-operative Ischemic Events After Indirect Revascularization Surgeries in Patients with Moyamoya Disease

ObjectiveRecurrent stroke after revascularization surgeries predicts poor outcome in patients with moyamoya disease (MMD). Early identification of patients with stroke risk paves the way for rescue intervention. This study aimed to investigate the role of ultrasound in identifying patients at risk of post-operative ischemic events (PIEs). MethodsThis prospective study enrolled patients with symptomatic MMD who underwent indirect revascularization surgeries. Ultrasound examinations were performed preoperatively and at 3 mo post-operatively to evaluate the hemodynamic changes in extracranial and intracranial arteries on the operated side. PIE was defined as ischemic stroke or transient ischemic attack in the operated hemisphere within 1 y. The areas under receiver operating characteristic curves were compared between models for prediction of PIE. ResultsA total of 56 operated hemispheres from 36 patients (mean age, 23.0 ± 18.5 y) were enrolled in this study, and 27% developed PIE. In multivariate logistic regression models, PIE was associated with lower end-diastolic velocity and flow volume (FV) of the ipsilateral external carotid artery (ECA), and lower FV of ipsilateral superficial temporal artery and occipital artery at 3 mo post-operatively (all p < 0.05). Moreover, the post-operative FV of the ipsilateral ECA was the only one factor that significantly increased the areas under receiver operating characteristic curves from 0.727 to 0.932 when adding to a clinical–angiographic model for prediction of PIE (p = 0.017). This parameter was significantly lower in hemispheres with PIE, both in adult and pediatric patients. ConclusionAfter indirect revascularization, surgeries in patients with symptomatic MMD, FV of ipsilateral ECA at 3 mo helps clinicians to identify patients at risk of PIE.

Objective Evaluation of Stellate Ganglion Block Effects Using Ultrasound Wave Intensity Technology: A Study on Hemodynamics.

Emerging evidence suggests that although Horner's syndrome manifests observable facial changes, it may not comprehensively evaluate the hemodynamic alterations associated with stellate ganglion block (SGB). This study endeavors to systematically evaluate the influence of SGB on the elasticity and flow velocity of the common carotid artery (CCA) and brachial artery utilizing ultrasound wave intensity analysis (usWIA). Particularly, it focuses on patients necessitating monitoring for its effects on specific organs or regions. Totally, we selected 33 patients, where only 31 patients (comprising 15 males and 16 females) were included between September 2020 to January 2022 after screening patients who require SGB treatment for painful disorders. The side on which the SGB was administered depended on the patient's painful side, 13 cases underwent left stellate ganglion block (LSGB), and 18 cases underwent right stellate ganglion block (RSGB). Wave intensity (WI) data were collected by usWIA on the CCA and brachial artery before the administration of SGB and after the manifestation of Horner's syndrome. We then compared the changes in these data pre- and post-SGB using SPSS 26.0. The results showed an increase in arterial compliance (AC) of the CCA and brachial artery on the blocked side after SGB (P < 0.05). In contrast, pressure-strain elastic modulus (EP) and arterial stiffness pulse wave velocity (PWVβ) decreased (for all P < 0.05). Furthermore, the minimum velocity (Vmin) of the CCA exhibited a significant increase (P < 0.01), while wave intensity pulse wave velocity (PWVwi) was significantly reduced (P < 0.01). In contrast, on the contralateral side of the CCA, EP and PWVβ increased after SGB (for all P < 0.05), while AC decreased (P < 0.05). SGB has been observed to enhance the elasticity and blood flow velocity of arteries within its innervated areas. In clinical practice, usWIA can serve as an objective measurement tool for assessing the impact of SGB on arterial elasticity and flow velocity in specific organs or regions. Furthermore, unilateral SGB has been noted to diminish the arterial elasticity of the CCA on the contralateral side.

Impact of yoga on the central and peripheral vascular function among desk-based workers: A single-centered trial study

Background The aim of this study was to observe and analyze vascular function in ‘prolonged sitting’, followed by a yoga asana routine and pranayama intervention. Participants in this study include those who work from desks in offices. The study required the participants to attend on three separate days at random, and they had to finish a computerized test on each day. On the first day, participants were required to complete a computer test while sitting still for four hours (with the exception of washroom breaks). The next day, they underwent a computerized test along with a pranayama intervention. Finally, on the last day, they underwent a computerized test along with a yoga asana intervention. At the start of the study and after two and four hours, we measured the diameter and velocity of the common carotid artery (CCA) and superficial femoral artery (SFA). Methods The study was a within-subjects prospective single-center trial conducted in the Department of Radio-Diagnosis and Imaging, Kasturba Medical Hospital, Manipal, India, between September 2022 and January 2023. Participants were asked to do one of the following ‘activities’ over successive weeks: Week 1 – Prolonged sitting; Week 2 – Pranayama intervention; and Week 3 – Yoga asana intervention during prolonged sitting. The baseline and follow-up variables of pulse velocity, endothelial thickness, and shear rate were assessed for normality through a Shapiro-Wilk Test. Results Our sample included 11 participants with moderate physical activity, five with high physical activity and one with low physical activity. Yoga asana intervention comprised participants sitting continuously for four hours, with a yoga asana intervention being provided every hour, lasting for 10 minutes. Conclusions Yoga asana improves vascular functions in prolonged sitting conditions. This routine can promote the concept of interrupted sitting and ways to reduce it with efficient yoga asana practice without changing the work culture and provide better physical relief. Trial registration Clinical Trials Registry – India ( CTRI/2022/09/045628), date of registration: 19/09/2022(CTRI/2022/9/045628)https://ctri.nic.in/Clinicaltrials/main1.php?EncHid=16349.27799,

Questioning the Role of Carotid Artery Ultrasound in Assessing Fluid Responsiveness in Critical Illness: A Systematic Review and Meta-Analysis.

A noninvasive and accurate method of identifying fluid responsiveness in hemodynamically unstable patients has long been sought by physicians. Carotid ultrasound (US) is one such modality previously canvassed for this purpose. The aim of this novel systematic review and meta-analysis is to investigate whether critically unwell patients who are requiring intravenous (IV) fluid resuscitation (fluid responders) can be identified accurately with carotid US. The protocol was registered with PROSPERO on the 30/11/2022 (ID number: CRD42022380284). Studies investigating carotid ultrasound accuracy in assessing fluid responsiveness in hemodynamically unstable patients were included. Studies were identified through searches of six databases, all run on 4 November 2022, Medline, Embase, Emcare, APA PsycInfo, CINAHL, and Cochrane Library. Risk of bias was assessed using the QUADAS-2 and the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) guidelines. Results were pooled, meta-analysis was conducted where amenable, and hierarchical summary receiver operating characteristic models were established to compare carotid ultrasound measures. Seventeen studies were included (n = 842), with 1048 fluid challenges. 441 (42.1%) were fluid responsive. Four different carotid US measures were investigated, including change in carotid doppler peak velocity (∆CDPV), carotid blood flow (CBF), change in carotid artery velocity time integral (∆CAVTI), and carotid flow time (CFT). Pooled carotid US had a pooled sensitivity, specificity, and AUROC with 95% confidence intervals (CI) of 0.73 (0.66-0.78), 0.82 (0.72-0.90), and 0.81 (0.78-0.85), respectively. ∆CDPV had sensitivity, specificity, and AUROC with 95% CI of 0.72 (0.64-0.80), 0.87 (0.73-0.94), and 0.82 (0.78-0.85), respectively. CBF had sensitivity, specificity, and AUROC with 95% CI of 0.70 (0.56-0.80), 0.80 (0.50-0.94), and 0.77 (0.78-0.85), respectively. Risk of bias and assessment was undertaken using the QUADAS-2 and GRADE tools. The QUADAS-2 found that studies generally had an unclear or high risk of bias but with low applicability concerns. The GRADE assessment showed that ∆CDPV and CBF had low accuracy for sensitivity and specificity. It appears that carotid US has a limited ability to predict fluid responsiveness in critically unwell patients. ∆CDPV demonstrates the greatest accuracy of all measures analyzed. Further high-quality studies using consistent study design would help confirm this.

Impact of yoga on the central and peripheral vascular function among desk-based workers: A single-centred trial study

Background The aim of this study was to observe and analyze vascular function in ‘prolonged sitting’, followed by a yoga routine and pranayama intervention. Participants in this study include those who work from desks in offices. The study required the participants to attend on three separate days at random, and they had to finish a computerized test on each day. On the first day, participants were required to complete a computer test while sitting still for four hours (with the exception of washroom breaks). The next day, they underwent a computerized test along with a pranayama intervention. Finally, on the last day, they underwent a computerized test along with a yoga intervention. At the start of the study and after two and four hours, we measured the diameter and velocity of the common carotid artery (CCA) and superficial femoral artery (SFA). Methods The study was a within-subjects prospective single-center trial conducted in the Department of Radio-Diagnosis and Imaging, Kasturba Medical Hospital, Manipal, India, between September 2022 and January 2023. Participants were asked to do one of the following ‘activities’ over successive weeks: Week 1 – Prolonged sitting; Week 2 – Pranayama intervention; and Week 3 – Yoga intervention during prolonged sitting. The baseline and follow-up variables of pulse velocity, endothelial thickness, and shear rate were assessed for normality through a Shapiro-Wilk Test. Results Our sample included 11 participants with moderate physical activity, five with high physical activity and one with low physical activity. Yoga intervention comprised participants sitting continuously for four hours, with a yoga session intervention being provided every hour, lasting for 10 minutes. Conclusions Yoga improves vascular functions in prolonged sitting conditions. This routine can promote the concept of interrupted sitting and ways to reduce it with efficient yoga practice without changing the work culture and provide better physical relief. Trial registration Clinical Trials Registry – India ( CTRI/2022/09/045628), date of registration: 19/09/2022(CTRI/2022/9/045628)https://ctri.nic.in/Clinicaltrials/main1.php?EncHid=16349.27799,

Cold stimulation of the oral cavity redistributes blood towards the brain in healthy volunteers.

The aim of this study was to analyze cold stimulation-induced changes in cerebral and cardiac hemodynamics. Upon ingestion of an ice cube, the changes in resistance index, mean flow velocity and flow index of the middle cerebral arteries (MCA) were assessed using transcranial Doppler sonography. Extracranial duplex sonography was used to measure the mean flow velocity and resistance index of the right internal carotid artery (ICA). The change in mean arterial pressure, heart rate, root mean square of successive differences (RMSSD) and end-tidal carbon dioxide pressure were analyzed additionally. These changes were compared to sham stimulation. Compared with sham stimulation, cooling of the oral cavity resulted in significant changes in cerebral and cardiac hemodynamics. The cold stimulation decreased the resistance index in the MCA (-4.5% ± 5.4%, p < 0.0001) and right ICA (-6.3% ± 15.6%, p = 0.001). This was accompanied by an increase in mean flow velocity (4.1% ± 8.0%, p < 0.0001) and flow index (10.1% ± 43.6%, p = 0.008) in the MCA. The cardiac effects caused an increase in mean arterial pressure (1.8% ± 11.2%, p = 0.017) and RMSSD (55% ± 112%, p = 0.048), while simultaneously decreasing the heart rate (-4.3% ± 9.6%, p = 0.0001). Cooling of the oral cavity resulted in substantial changes in cerebral and cardiac hemodynamics resulting in a blood flow diversion to the brain.

The left ventricular outflow tract and carotid artery velocity time integrals

The left ventricular outflow tract velocity time integral (LVOT VTI) is commonly used in the intensive care unit as a measure of stroke volume (SV) and how the SV changes in response to an intervention; therefore, the LVOT VTI is used to guide intravenous fluid management. Various peripheral Doppler surrogates are proposed to infer the LVOT VTI (e.g., measures from the common carotid artery). A recently-described, novel method of insonation has an excellent ability to detect change in the LVOT VTI. This approach raises important facets of Doppler flow and insonation error, as well as the general principles at play when using a peripheral artery to infer changes from the left ventricle. Relating the VTI of a peripheral artery to the LVOT VTI was recently described mathematically and may help clinicians think about the Doppler relationship between central and peripheral flow.

Predicting fluid responsiveness in spontaneously breathing parturients undergoing caesarean section via carotid artery blood flow and velocity time integral measured by carotid ultrasound: a prospective cohort study

BackgroundPresent evidence suggests that the Doppler ultrasonographic indices, such as carotid artery blood flow (CABF) and velocity time integral (VTI), had the ability to predict fluid responsiveness in non-obstetric patients. The purpose of this study was to assess their capacity to predict fluid responsiveness in spontaneous breathing parturients undergoing caesarean section and to determine the effect of detecting and management of hypovolemia (fluid responsiveness) on the incidence of hypotension after anaesthesia.MethodsA total of 72 full term singleton parturients undergoing elective caesarean section were enrolled in this study. CABF, VTI, and hemodynamic parameters were recorded before and after fluid challenge and assessed by carotid artery ultrasonography. Fluid responsiveness was defined as an increase in stroke volume index (SVI) of 15% or more after the fluid challenge.ResultsThirty-one (43%) patients were fluid responders. The area under the ROC curve to predict fluid responsiveness for CABF and VTI were 0.803 (95% CI, 0.701–0.905) and 0.821 (95% CI, 0.720–0.922). The optimal cut-off values of CABF and VTI for fluid responsiveness was 175.9 ml/min (sensitivity of 74.0%; specificity of 78.0%) and 8.7 cm/s (sensitivity of 67.0%; specificity of 90.0%). The grey zone for CABF and VTI were 114.2-175.9 ml/min and 6.8–8.7 cm/s. The incidence of hypotension after the combined spinal-epidural anaesthesia (CSEA) was significantly higher in the Responders group 25.8% (8/31) than in the Non-Responders group 17.1(7/41) (P < 0.001). The total incidence of hypotension after CSEA of the two groups was 20.8% (15/72).ConclusionsUltrasound evaluation of CABF and VTI seem to be the feasible parameters to predict fluid responsiveness in parturients undergoing elective caesarean section and detecting and management of hypovolemia (fluid responsiveness) could significantly decrease incidence of hypotension after anaesthesia.Trial registrationThe trial was registered at the Chinese Clinical Trial Registry (ChiCTR) (www.chictr.org), registration number was ChiCTR1900022327 (The website link: https://www.chictr.org.cn/showproj.html?proj=37271 ) and the date of trial registration was in April 5, 2019. This study was performed in accordance with the Declaration of Helsinki and approved by the Research Ethics Committee of Women’s Hospital, Zhejiang University School of Medicine (20,180,120).

Rapid Carotid Screening by Duplex: A Prospective Single Centre Assessment.

A novel carotid quick scan (CQS) protocol was developed to rapidly screen for carotid atherosclerosis greater than 50% stenosis in a vascular outpatient setting. This study assessed accuracy and time saved. The CQS was developed by consensus agreement between vascular surgeons and accredited clinical vascular scientists through a modified Delphi technique. The protocol comprised a rapid B-mode then colour flow transverse sweep of the common and internal carotid arteries, with internal carotid artery velocity assessment. One hundred outpatients attending with peripheral artery disease or abdominal aortic aneurysm were recruited. CQS sensitivity, specificity and accuracy was assessed against a conventional full carotid duplex study, performed to UK and ESVS guidelines. Twenty four percent of patients (n = 100) had >50% carotid NASCET stenosis. CQS achieved an excellent accuracy of 96.5% in detecting >50% stenosis when compared to full duplex; Cohen's ƙ = .88, (95%CI .79-.97; P < .001), sensitivity 91.4%, specificity 97.6%, positive predictive value (PPV) 88.9% and negative predictive value (NPV) 98.2%. Median (IQR) time to complete the CQS was 13 sec (±12) per side, compared to 151 sec (±78) per side for the full carotid duplex. In the presence of >50% carotid disease, median CQS time was 25 sec (±31) per side compared to 214 (±104) by full scan. CQS as a carotid screening tool is rapid, accurate and acceptable to the population and workforce. It would be simple to roll out in all vascular laboratories to reduce the time and cost burden of excluding significant carotid disease in any group.

Abstract 197: Establishing a Novel Pulse Wave Velocity-Guided Mouse Model of Cardiac Arrest With Different Durations

Background: Neurological and cardiovascular injuries are the leading causes of death following cardiac arrest (CA). Few rodent models recapitulate these post-resuscitation symptoms. Aims: To develop extended ischemic CA models under Pulse Wave Velocity ( PWV) guidance with consistent post-CA brain injury (PCABI) and coronary dysfunction as potential therapeutic targets and mechanical studies. Methods: Forty-eight mice were randomized into four experimental groups (control, 8-, 12-, and 16-min CA). Potassium chloride (KCL) was intravenously injected, resulting in immediate asystole. Mice were resuscitated with an injection of epinephrine and manual chest compressions. PWV was monitored for the left carotid artery velocity and coronary flow reserve (CFR). Resuscitability, synaptic density in the hippocampal CA1 region, blood-brain barrier (BBB), and neurologic deficit scores (NDS) were also evaluated. Results: The PWV could monitor rapid asystole after KCL injection, improve cardiopulmonary resuscitation (CPR) success rates, and avoid the pre-matured end of resuscitation. Compared to the standard control, mice with 8-min CA had preserved CFR, mild loss of synaptic density (p&gt;0.05), mild hypothermal, and a normal electrocardiogram. They maintained BBB integrity with no significant change to neurologic function. Compared with a 92% CPR success rate in 8 min-CA mice, 12 min-CA mice had 83%, and 16 min-CA mice had 58% resuscitability. Twelve min-CA mice had significantly impaired CFR at 24 hours and high lethality (40%, P&lt;0.05) within the first three days; 16 min-CA mice worsened (33% survival rate, p&lt;0.01). The 24 hrs electron microscope showed that CA-induced synaptic vesicle densities were ischemic time-dependent [350±60 (control) vs. 289±64 (8 min CA) vs. 269±34 (12 min CA) vs. 181±41/field (16 min CA)], consistent with NDS. The cerebrum and hippocampus were the most valuable regions, indicated by Evans blue evaluation at 48 hrs after CA. Conclusions: We established elongated PWV-guided CA models as with successful CPR, post-CA neurological deficits, leaky BBB, loss of synaptic density, coronary endothelial dysfunction, and even death in mice, which closely recapitulated the post-resuscitation symptoms in survived patients after CPR.

Abstract 318: Glibenclamide May Have a Neuroprotective and Cardioprotective Role Beyond Cerebral Edema in an Asphyxial Model of Cardiac Arrest

Background: Cardiac arrest (CA) is a leading cause of mortality and long-term disability. There are no therapeutics approved for neuro- and cardio-protection. Novel therapeutics are urgently needed to improve patient outcomes. Glibenclamide is a second-generation sulfonylurea drug and inhibitor of SUR1-TRPM4. Little is known about its role in cardioprotection and synaptic density. Aims: To evaluate the effect of glibenclamide on coronary flow reserve (CFR), blood-brain barrier (BBB) permeability, and synaptic density in an asphyxial mouse model of CA. Methods: We used an asphyxial mouse model of CA; potassium chloride was injected into the right internal jugular vein, resulting in asystole. Chest compressions and epinephrine were administered following 12 minutes of no-flow time. Successfully resuscitated mice (n=24) were randomized to receive intravenous glibenclamide or vehicle; the glibenclamide group received a loading dose of 10 μg/kg immediately upon return of spontaneous circulation followed by 1.6 μg every 12 hours up to day 3. Pulse Doppler Velocity (PWV) was used to monitor the CFR and left carotid artery velocity. Synaptic density was quantified with ex vivo autoradiographs after injection of 18 F-SynVesT-2 in the brain (3, 24, and 72 hrs). Evans blue staining and general neurologic deficit scores were assessed 24 hours post-resuscitation. Results: Treatment with glibenclamide resulted in an increase in CFR (1.37±0.11 vs. 1.17±0.06, p=0.01) and carotid peak velocity (61.38±12.81 cm/s vs. 46.83±6.3 cm/s, p&lt;0.05). Whole brain synaptic density was increased in the mice treated with glibenclamide, suggesting a reduction in synaptic density loss. BBB disruption in the cerebrum was significantly lower in Glibenclamide treated mice (0.00022±0.000014/mg vs. 0.000471±0.000088/mg, p&lt;0.01). Mice treated with Glibenclamide had lower neurologic deficit scores (1.83±2.89 vs 4.75±3.84, p&lt;0.05). Conclusions: Glibenclamide given immediately following the return of spontaneous circulation improved CFR, decreased BBB disruption, reduced synaptic density loss, and improved neurologic deficit scores, suggesting both cardio- and neuro-protective effects.

Reduced reward responsiveness in treatment resistant depression of middle-aged adults: Association with carotid artery stiffness and tetrahydrobiopterin.

Nearly one third of the population diagnosed with major depressive disorder (MDD) fail to respond to two or more antidepressant drugs of adequate dose and duration. This necessitates identification of confounding psychological and physiological factors that could contribute to treatment resistant depression (TRD). The present longitudinal study investigated the influence of behavioural inhibition system (BIS) and behavioural approach system (BAS) in treatment resistance. Further, the association of depression severity with physiological factors contributing to arterial stiffness was also investigated. Baseline data was acquired from 101 middle-aged (36-56 years) patients on immediate diagnosis with MDD using DSM-V criteria. Follow ups were conducted at 06 months and 12 months during treatment. Psychological assessment battery at baseline and follow ups comprised of Hamilton depression rating (HAM-D) for depression severity, WHODAS-2 and BIS-BAS score. Atherosclerosis and central arterial stiffness were measured by intima-media thickness of internal carotid artery and brachial-ankle pulse wave velocity. Physiological factors influencing central vascular function viz., body-mass index, estimated glomerular filtration rate, HbA1c, central systolic and diastolic blood pressure, heart rate and tetrahydrobiopterin were also investigated. Our results show lower reward responsiveness (BAS-RR) and higher BIS scores in TRD patients along with differentially higher intima-media thickness of left internal carotid artery. Higher depression severity at all stages of the study was correlated with lower tetrahydrobiopterin and BAS-RR scores. We, therefore, suggest that vascular depression resulting due to increased intima-media thickness of left carotid artery and lower tetrahydrobiopterin could be contributing factors for treatment resistance in middle-aged MDD patients.

Handgrip exercise does not alter CO2 -mediated cerebrovascular flow-mediated dilation.

Handgrip exercise (HG), a small muscle exercise, improves cognitive function and is expected to provide a useful exercise mode to maintain cerebral health. However, the effect of HG on cerebral blood flow regulation is not fully understood. The present study aimed to examine the effect of acute HG on cerebral endothelial function as one of the essential cerebral blood flow regulatory functions. Thirteen healthy young participants performed interval HG, consisting of 4 sets of 2min HG at 25% of maximum voluntary contraction with 3min recovery between each set. Cognitive performance was evaluated before and at 5 and 60min after interval HG using the Go/No-Go task (reaction time and accuracy). The diameter and blood velocity of the internal carotid artery (ICA) were measured using a duplex Doppler ultrasound system. To assess cerebral endothelial function, hypercapnia (30s of hypercapnia stimulation, end-tidal partial pressure of CO2 : +9mmHg)-induced cerebrovascular flow-mediated dilatation (cFMD) was induced, calculated as relative peak dilatation from baseline diameter. The shear rate (SR) was calculated using the diameter and blood velocity of the ICA. As a result, cognitive performance improved only at 5min after interval HG (reaction time, P=0.008; accuracy, P=0.186), whereas ICA SR during interval HG and cFMD after interval HG were unchanged (P=0.313 and P=0.440, respectively). These results suggest that enhancement in cerebral endothelial function is not an essential mechanism responsible for acute HG-induced cognitive improvement. NEW FINDINGS: What is the central question of this study? Does handgrip exercise, a small muscle exercise, improve cerebral endothelial function? What is the main finding and its importance? Acute interval isometric handgrip exercise (2min of exercise at 25% maximum voluntary contraction, followed by 3min of recovery, repeated for a total of 4 sets) did not improve cerebral endothelial function. Since the cerebrovascular shear rate did not change during exercise, it is possible that acute handgrip exercise is not sufficient stimulation to improve cerebral endothelial function.

Association of Serum Uric Acid Levels with Peripheral Arterial Disease

Abstract Background Peripheral arterial disease (PAD) is a chronic atherosclerotic process that causes narrowing or aneurysms of the peripheral arterial vasculature, predominantly of the lower limbs. It has an estimated worldwide prevalence of up to 10%, increasing to nearly 30% in patients more than 50 years of age. Various risk factors are included in this process. This study will evaluate the relationship of increased serum uric acid levels with the prevalence of peripheral arterial disease. Objective In this study we aim to evaluate the relationship of increased serum uric acid level with peripheral arterial disease through evaluation of ABI &amp; CIMT. Patients and Methods This was a case control study carried on 100 subjects, divided into two groups: The first group (the case group) composed of 50 subjects identified as having peripheral arterial disease (PAD), were recruited from vascular surgery department. The second group (the control group) composed of 50 subjects who matched the participants in group I in age &amp; sex, had traditional cardio vascular risk factors, but free from PAD, they were recruited from the outpatient clinics, The study was held during the period between September 2019 &amp; October 2020. An informed consent was done, the steps of research were explained for the subjects with the protection of their privacy and confidentiality. Moreover, the ethical committee of faculty of medicine of Ain Shams university approved the study. Results Uric acid (UA) &amp; CIMT showed highly significant difference among both groups (P-values = 0.003). Low ABI was significantly associated with UA among the patients group (P-value = 0.003). After further subdividing UA levels among subjects into tertiles the negative relation with ABI remained highly significant, the highest tertile of UA showed the lowest ABI (P-value = 0.006) However, the correlation with CIMT remained non- significant (P-value = 0.159) although people in the highest tertile exhibited higher CIMT values than in the lowest one. Logistic regression analysis showed uric acid levels were significantly associated with PAD (OR = 1.3, P-value = 0.006). However, after adjustment of confounding risk factors, that correlation became nonsignificant (OR = 2.165 P-value = 0.227 CI 95%(&amp; remained significant only for BMI, DM &amp;dyslipidemia. Conclusion We concluded that ABI was decreased among UA tertiles (P-value = 0.006), denoting a probable relation of UA with lower limb atherosclerosis. CIMT was non-significantly correlated with UA (P-value = 0.651), however the highest UA tertile showed the highest CIMT values (P-value = 0.159). Among our subjects, Uric acid was significantly associated with PAD (Odds Ratio = 1.37, P-value = 0.006). However, after adjustment for other confounding factors that association became non-significant (Odds Ratio=2, P-value = 0.227). Abbreviations PAD: Peripheral Arterial Disease; XOR: Xanthine Oxidoreductase; TIA: Transient Ischemic Attack; ABI: Ankle Brachial Index; PVD: Peripheral Vascular Disease; CIMT: Carotid Intima-Media Thickness; CT: Computed Tomography; LL: Lower Limb; UL: Upper Limb; DM: Diabetes Mellitus; HTN: Hypertension; LS: Longitudinal Section; CCA: Common Carotid Artery; BMI: Body Mass Index; UA: Uric Acid; CAVI: Carotid Artery Velocity Index; ba-PWV: Brachial Ankle Pulsed Wave Velocity

Effects of physical activity breaks during prolonged sitting on vascular and executive function—A randomised cross-over trial

ObjectivesHigh sedentary behaviour is associated with adverse effects on central vascular function and cognitive function. Although interventions to mitigate the adverse effects of workplace sitting are intriguing, evidence of the efficacy of such interventions remains lacking. This randomised cross-over trial was aimed at exploring the effectiveness of prolonged sitting, with or without physical activity breaks, on central, peripheral vascular and cognitive function in adults. MethodsTwenty one healthy adults completed 4 h of simulated work conditions in three experimental visits: (1) uninterrupted sitting (SIT); (2) sitting interrupted by 3 min of walking every hour (LIT); and (3) sitting interrupted by 3 min of stair climbing every hour (MIT). Carotid (CA) and superficial femoral artery (SFA) diameter, velocity, shear rate and blood flow were measured with Duplex ultrasound at 50 MHz at three time points (hours 0, 2 and 4), and executive function was assessed with the computer based Eriksen Flanker task every hour. ResultsThe decreases in reaction time (−30.59%) and accuracy (−10.56%) during SIT conditions were statistically significant, and less of a decrease was observed under LIT and MIT conditions. No significant differences in CA and SFA function were observed with LIT and MIT interventions. ConclusionPhysical activity breaks of varying intensity during prolonged sitting improve reaction time. However, the vascular benefits of physical activity breaks should be confirmed in the future through long term studies in natural environment.

Abstract WP102: Side-to-side Relative Reduction In End-diastolic Velocity Of The Common Carotid Artery For Emergent Discrimination Of Anterior Circulation Large Vessel Occlusion

Introduction: Side-to-side relative reduction in end-diastolic velocity (EDV) of the common carotid artery (CCA) may discriminate ipsilateral anterior circulation large vessel occlusion (LVO), which will contribute faster patient triage for reperfusion therapy. We evaluated the discriminative accuracy of this simple sonographic index for anterior circulation LVO in acute stroke population, including intracerebral hemorrhage (ICH). Methods: Among patients with acute stroke admitted to our institute between 2016-2018, those who underwent both carotid ultrasonography and head MRA or CTA within 24 hours after last known normal time were reviewed. Relative EDV reduction was calculated as a ratio by dividing the CCA EDV lower side by the EDV higher side. Anterior circulation LVO was defined as occlusion of the internal carotid artery (ICA) or M1 segment of the middle cerebral artery on the lower EDV side. Discriminative performance of relative EDV reduction for anterior circulation LVO was assessed by receiver operating characteristics analysis. Results: A total of 688 patients (411 males; median age 77 years; 87 with anterior circulation LVO) were analyzed. When compared to no occlusion, value of relative EDV reduction was remarkably lower in ICA occlusion, followed by that in M1 occlusion (Figure). Area under the curve (AUC) of relative EDV reduction for ICA occlusion was 0.96 (95% confidence interval [CI] 0.94-0.99) with an appropriate cut-off value of 0.50 (sensitivity 94%, specificity 94%). When the discrimination target was set to anterior circulation LVO, the AUC was 0.78 (95% CI 0.72-0.85) with an appropriate cut-off value of 0.67 (sensitivity 69%, specificity 83%). At this cut-point, 51% of patients with M1 occlusion was classified as false negative. Conclusions: The discriminative performance of the relative CCA EDV reduction in acute stroke population was excellent for ICA occlusion and acceptable for anterior circulation LVO.

Handheld versus conventional ultrasound for assessing carotid artery in routine volunteers.

Carotid ultrasound is a key tool for the diagnosis and evaluation of cardio disease, and the measurement of carotid intima-media thickness (CIMT) and hemodynamic parameters is of paramount importance for the imaging method. The aim of this study was to evaluate the feasibility and accuracy of handheld ultrasound devices for measuring carotid parameters. We performed a carotid ultrasound on 25 participants using a handheld ultrasound device and a conventional ultrasound machine. For each participant, max and mean CIMT of common carotid artery (CCA) and peak systolic velocity (PSV), end diastolic velocity (EDV) and resistive index (RI) of CCA, bilateral external carotid artery (ECA), internal carotid artery (ICA) and the vertebral artery were measured. Agreement and repeatability were evaluated by linear regression and Bland-Altman analysis. We found a good repeatability and consistent of handheld ultrasound device in measuring mean CIMT (r = 0.68, P < 0.01). Furthermore, there was a moderate to good agreement between handheld and conventional ultrasound systems in measuring max IMT, mean IMT, PSV, EDV and RI of CCA (0.73, 0.79, 0.52, 0.58 and 0.84, respectively). Handheld ultrasound devices were able to provide carotid IMT and hemodynamic parameters measurements similar to those of conventional ultrasound. Such capabilities of handheld ultrasound devices might be useful for the primary assessment of carotid in clinical work.