Flow-mediated Dilation Values Research Articles

Abstract 4134277: Impairment of Vascular Endothelial Function by Inhalation of Smoke or Aerosol from Tobacco and Marijuana Products is Dependent on Vagus Nerve Input from the Airway

Background: Smoke or vaporizer aerosol from different tobacco or marijuana products can cause vascular endothelial dysfunction in humans and rodents. Mechanisms of acute smoke-induced endothelial dysfunction are complex and remain ambiguous. We reported that endothelial functional impairment by tobacco smoke is dependent on intact vagus nerves, leading us to hypothesize that endothelial function impaired by smoke/aerosol from tobacco or marijuana relies on vagal input from the airway. Methods: We used Sprague-Dawley rats at 10-12 weeks of age (n=8/group; 4M+4F). Rats were anesthetized by ketamine/xylazine and exposed to one session of exposure to smoke/aerosol of tobacco (Marlboro Red) or marijuana (~10% THC) cigarettes, e-cigarettes (JUUL), or IQOS (American HeatSticks). Exposure was pulsatile (10 cycles of 5s 2x/min for 5 min via nosecone). Endothelial function was assessed as flow-mediated dilation (FMD) in the femoral artery pre- (baseline) and post-exposure. Surgical bilateral cervical vagotomy was performed in the anesthetized rats post-baseline FMD (before exposure). Sham surgical procedures were carried out without severing vagus nerves. We used paired Student t tests to compare FMD values in each group pre- and post-exposure. Significance was P <.05. Results: FMD was decreased from pre- to post-exposure in all exposed sham groups as expected, whereas the impairment of FMD by smoke/aerosol exposure was completely abrogated in all vagotomized groups (Figure), with no apparent effect of sex. The pre- vs. post-exposure FMD values (mean±SD) in exposed sham groups were 16.0±3.0% vs. 6.7±3.1% for tobacco cigarettes, 13.1±2.3% vs. 5.0±2.3% for JUUL, 14.3±3.0% vs. 6.0±2.2% for IQOS, and 16.2±4.9% vs. 7.1±3.6% for marijuana. For exposed vagotomized groups, pre- vs. post-exposure FMD values were 13.3±3.7% vs. 12.6±3.7% for tobacco cigarettes, 12.8±2.6% vs. 13.0±3.2% for JUUL, 13.9±2.2% vs. 13.3±2.7% for IQOS, and 14.4±4.2% vs. 15.1±5.0% for marijuana. Heart rate was increased and respiratory rate was decreased in vagotomized groups as expected. Conclusions: Inhaling smoke or aerosol causes vascular endothelial impairment via a common mechanism involving vagal stimulation from the airway.

Ultrasound assessment of endothelial dysfunction in Egyptian migraine patients

BackgroundIt becomes clearer that migraine is associated with vascular risks; however, preclinical vascular involvement is not sufficiently addressed. Evidences point that migraine attacks affect vascular endothelium. The aim of this study was to investigate endothelial dysfunction in migraineurs through assessment of carotid intima-media thickness (CIMT) and flow-mediated dilatation (FMD) of the brachial artery and their correlation with clinical characteristics of migraine, headache severity, and brain magnetic resonance imaging (MRI) findings.ResultsA statistically significant difference was found between migraineurs and controls where carotid IMT was significantly higher and FMD of the brachial artery was significantly lower in migraineurs compared to controls. Carotid IMT was significantly higher and FMD was significantly lower in chronic migraine compared to episodic migraine patients. Mean IMT values were significantly higher in patients receiving ergots and in patients with subcortical white matter lesions in brain MRI. Mean FMD values were significantly lower in patients receiving ergots. There was a significant negative correlation between FMD and carotid IMT, age of the patients, disease duration, duration of headache attacks, headache frequency, and migraine disability assessment questionnaire (MIDAS) score. There were significant positive correlations between carotid IMT and age of patients, disease duration, headache frequency, MIDAS score, and number of MRI white matter lesions. For diagnosing endothelial dysfunction in migraineurs, the sensitivity and specificity of IMT were 72.5 and 70%, respectively, with a cut-off value of 0.575 mm and that of FMD were 82.5 and 90%, respectively, with a cut-off value of 20.55%.ConclusionMigraine coincides with endothelial dysfunction which promotes atherogenesis and increased risk of cerebral ischemia. FMD could be used as a potential biomarker for endothelial dysfunction in migraine. The affection of IMT and FMD is more in patients receiving ergots which may influence the selection of treatment in migraineurs in the future.

Lower modified rodnan skin score values and complement 4 levels are associated with arterial endothelial dysfunction in patients with systemic sclerosis

Abstract Background Systemic sclerosis (SSc) is a multisystem autoimmune disease affecting skin and multiple organs. Although immunopathological evidence supports direct arterial involvement leading to tissue ischemia in SSc, factors associated with arterial involvement are not precisely determined due to the rarity of SSc. In this study, we aimed to investigate aortic stiffness and endothelial functions in patients with SSc. Methods Patients under treatment of our Rheumatology department and healthy controls have been included in our study. Aortic stiffness was examined by pulse wave velocity (PWV) exam and endothelial functions were assessed by flow mediated dilation (FMD). Individuals with known atherosclerotic risk factors were excluded from our study. A thorough biochemical examination of all individuals and immunologic markers of patients with SSc was completed. All of the organ involvements in patients with SSc were noted and modified Rodnan skin score (MRSS) was calculated. Results A total of 61 patients and 75 healthy controls were included in our study. Brachial-ankle PWV values were significantly higher (6.89±0.93 vs 6.49±0.22 m/sec; p:0.001) and brachial FMD values were significantly lower (16.7±6.7 % vs 18.7±3.8 %; p: 0.03) in patients with SSc. We have also grouped individuals according to severe FMD impairment (FMD < 10%). None of the healthy controls had severe impairment whereas 15 patients with SSc had FMD values lower than 10%. Higher anti-smooth muscle (Sm) antibody positiveness (40 % vs 15.4 %), lower complement 4 levels (23.6±16.7 vs 31.1±11.1 mg/dL), higher plasma iron values (70.3±43.6 vs 31.4±45.2 mcg/dL) and lower MRSS values (11.4±4.8 vs 20.7±10.9) were observed in SSc patients with severe FMD impairment. When we have put these variables in multivariate logistic regression analysis (backward elimination model), we have found an independent association of complement 4 levels (OR: 0.03, [95 % CI: 0.01-0.491], p:0.04) and MRSS values (OR: 0.853, [95 % CI: 0.761-0.955], p:0.006) with significant FMD impairment in patients with SSc. Conclusion Arterial stiffness is significantly increased and endothelial functions, as assessed by FMD is significantly decreased in patients with SSc, when compared to healthy controls. Lower complement 4 levels and lower modified Rodnan skin scores seem to be independently associated with significant severe FMD impairment. Although our study included a remarkable amount of patients with SSc, an infrequent autoimmune disease, number of patients included in our study is not adequate to make more precise comments. Further prospective studies with higher amount of patients are required for certain results.

Early impairment of endothelial and myocardial function in patients with hidradenitis suppurativa

Abstract Background/Introduction Hidradenitis suppurativa (HS) is a chronic, recurrent, debilitating, inflammatory skin disease manifested by painful, deep-seated, inflamed lesions of the apocrine gland-bearing areas of the body (axillae, submammary folds, inguinal and anogenital region). HS has been associated, among others, with an increased cardiovascular risk. Purpose We aimed to investigate the endothelial, arterial and left ventricular (LV) myocardial function in patients with severe HS. Methods Twenty-eight, not previously treated patients (mean age: 36 ± 13 years) with Hurley stage III disease and a mean score of 19±8 on the International Hidradenitis Suppurativa Severity Score System (IHS4) scale, were studied. Twenty healthy sex-, age- and body mass index -matched individuals, who were also weighted for common cardiovascular risk factors, served as the control group. Both patients and controls were evaluated for: a) perfused boundary region (PBR) of the sublingual microvessels with a diameter of 5-25 μm (an increased PBR value is considered as an indicator of a decrease in thickness of the endothelial glycocalyx), using a dedicated camera (Microscan, GlycoCheck), b) carotid-femoral pulse wave velocity (PWV-Complior), c) flow-mediated dilation (FMD) of the brachial artery and d) LV global longitudinal strain (GLS) using the speckle-tracking echocardiography. Results Compared to healthy controls, HS patients had increased PBR value (2.32 ± 0.19 vs. 1.99 ± 0.14 μm, p < 0.001) and decreased FMD (5.7 ± 2.9 vs. 10.3 ± 1.9 %, p < 0.001) and GLS values (-18.6 ± 2.8 vs. -22.5 ± 2.3 %, p < 0.001). In contrast, similar PWV values (9.2 ± 2 vs. 9.1 ± 1.9 m/s, p = 0.937) were recorded between patients and controls (Table). Increased IHS4 score (more severe disease) was associated with increased PBR values (r = 0.42, p = 0.026) and decreased FMD values (r = -0.37, p = 0.045). Conclusion Patients with HS show early impairment of endothelial and LV myocardial function, which correlates with the severity of the underlying systemic inflammation.Table

Effects of SGLT-2i and GLP-1RA in vascular function parameters: the impact of the weight loss

Abstract Background Arterial stiffness and endothelial function markers flag increased cardiovascular disease risk in patients with type 2 Diabetes Mellitus (T2DM), while weight management plays a crucial role for the management of glycemic control and prevention of complications in these patients. Purpose To investigate the effects of novel antidiabetic agents on arterial stiffness and endothelial function as well as the metabolic parameters of HbA1c and Weight in T2DM patients. Patients and Methods: We enrolled 99 consecutive patients under stable antidiabetic therapy who did not reach therapeutic targets. Subjects were assessed to receive an additional antidiabetic agent to optimize glucose control; glucagon like peptide-1 receptor agonist (GLP-1RA, n=50) or sodium/glucose cotransporter-2 inhibitor (SGLT-2i, n=49). Glycosylated hemoglobin (Hba1c) and weight expressed through Body Mass Index (BMI) along with carotid-femoral pulse wave velocity (PWV) and flow-mediated dilatation (FMD), as biomarkers of arterial stiffness and endothelial function accordingly, were measured at baseline and 3 months after treatment intensification. Results There were no differences between the study groups in traditional risk factors of age and sex or baseline HbA1c, BMI, PWV, and FMD levels (ps=NS for all). In both groups PWV values displayed a statistically significant improvement from 11.2±2.5 to 9.3±2.2 m/sec (p<0.001) in the GLP-1RA group and from 10.7±2.4 to 8.9±2.0 m/sec (p=0.001) in the SGLT-2i group, as presented in Figure 1 through the differences in the values of PWV. FMD values were also significantly improve in both groups from baseline to follow-up; from 6.04±1.22 to 6.50±1.26% (p<0,001) for the GLP-1RA group and from 6.38±1.21 to 6.81±1.29% (p<0.001) for the SGLT-2i group. Moreover, both groups achieved better weight management goals in terms of BMI values between baseline and follow-up; from 33.6±4.9 to 31.5±4.6 kg/m2 for the GLP-1RA group (p<0.001) and from 31.8±5.5 to 30.5±5.6 kg/m2 for the SGLT-2i group (p<0.001), in addition to achieving better glycemic control in terms of HbA1c values, as seen in their paired differences: for GLP-1RA: 1.3±0.7% and for SGLT-2i: 0.8±0.5%. Interestingly, in the SGLT-2i group the magnitude of the PWV improvement was correlated with the weight loss (r=0.368, p=0.007). Conclusion These data provide evidence that the newer antidiabetic drugs, both GLP1-RA and SGLT-2i, have actions that benefit both vascular function, endothelium as well as metabolic parameters. Interestingly, in the patients receiving SGLT-2i the magnitude of the PWV improvement was correlated with the weight loss.delta PWV for SGLT-2i & GLP-1RA groupsCorrelation of deltaWeight & deltaPWV

The effect of 6-month treatment with coenzyme Q10 on endothelial, vascular and myocardial function in patients with nonalcoholic fatty liver disease

Abstract Background Patients with Non-alcoholic fatty liver disease (NAFLD) hold an increased cardiovascular risk and present impaired markers of vascular, endothelial and myocardial function. Coenzyme Q10 (CQ10) is a powerful antioxidant that enhances mitochondrial function. Patients/methods: 52 patients (52±10 years old) with NAFLD were randomized to 240 mg CQ10 (n=25) or placebo (n=27). We measured at baseline and at six months post-treatment: i) Perfused boundary Region (PBR) of the sublingual arterial microvessels (Microscan, Glycocheck), ii) Carotid femoral pulse wave velocity - PWV (Complior ALAM), iii) Flow-mediated dilation (FMD) of the brachial artery, iv) Global left ventricular longitudinal strain (GLS) by speckle tracking imaging, v) Controlled attenuation parameter (CAP) measurement (FibroScan, Echosens). Results Six months post treatment with cQ10, values of PBR (2.12±0.19 vs. 2.28±0.23 μm), PWV (9.5±2.3 vs. 10.5±2.4m/s), CAP score (278.1±50, 2 vs. 305.3±44.5dB/m), FMD (6.61±4 vs. 5.02±2.6 %) and GLS (-19.3±1.9 vs -18.2±2 %) were improved (p<0.05 for all comparisons). On the contrary, the patients who were treated with placebo did not show statistically significant differences in PBR, PWV, CAP score, FMD and GLS after from 6 months (p>0.05). In the patients who received cQ10, the percentage reduction of CAP score at 6 months was directly proportional to the percent reduction in PWV (r=0.31, p=0.045) and inversely proportional to the percentage increase in FMD (r=-0.58, p=0.014). Conclusion Six-month treatment with CoQ10 reduces liver steatosis in patients with NAFLD. CoQ10 is associated with improved endothelial, vascular and LV myocardial function in patients with NAFLD.

Patients vaccinated against COVID-19 present better coronary flow, myocardial work and NTproNP levels than non-vaccinated at 4 months post COVID infection

Abstract Introduction COVID-19 affected patients present impaired subclinical markers of cardiovascular and endothelial function post resolution of infection. Whether vaccination impedes impairment of myocardial and vascular function has not been clarified. Purpose We investigated the effect of COVID-19 infection on markers of endothelial, vascular and myocardial function in vaccinated and non-vaccinated subjects at four months after the infection. Methods We recruited 60 vaccinated and 60 non-vaccinated patients with similar clinical characteristics, who were examined in a dedicated post-COVID-19 outpatient clinic during a scheduled follow-up visit at four months after a confirmed COVID-19 infection. We measured (i) perfused boundary region (PBR) of the sublingual arterial (increased PBR indicates reduced endothelial glycocalyx thickness), (ii) flow-mediated dilatation (FMD), (iii) coronary flow reserve (CFR) by Doppler echocardiography, (iv) pulse wave velocity (PWV) and central systolic blood pressure (cSBP), (v) global left and right ventricular longitudinal strain (GLS), (vi) myocardial global work index (GWI) global constructive work (GCW), global wasted work (GWW) and the myocardial global work efficiency (GWE) and v) NTproBNP blood levels. Results Among vaccinated patients 54,2% had mild disease, 33,3% had moderate disease and 12,5% had severe disease, while among non-vaccinated 29,1% had mild disease, 32,9% had moderate disease and 38% had severe disease(p<0.05). At four months, vaccinated patients presented with higher LVGLS, GCW values and CFR compared to non-vaccinated (p>0.05 table), while GWI, GWW and GWE were similar between the two groups(p>0.5). Moreover, in vaccinated patients RVGLS and RV FWLS were significantly higher than in non-vaccinated patients (p>0.05). Also, NTproBNP leves were significantly lower in vaccinated than in non-vaccinated patients (p<0.05). At four months, in vaccinated patients , we observed a marginally lower brachial and central systolic blood pressure compared with non-vaccinated (p=0.045, p=0.048 respectively.) Vaccinated patients displayed similar FMD and PWV values compared to non-vaccinated (p>0.05 for all the comparisons). Conclusion Patients vaccinated against COVID-19 suffered from milder disease resulting to better cardiac function and lower NTproNP levels than non-vaccinated 4 months post COVID infection.

The relationship between exercise-related hypertension and carotid artery intima media thickness and brachial artery endothelial function

Aims: Hypertension is one of the most common chronic diseases in the world. There are some non-invasive tests which are used to assess end organ damages in patients with hypertension. The purpose of this study is to show relationship between carotid artery intima media thickness (CIMT) and flow mediated dilatation (FMD) in patients with exercise induced hypertension (EIH). Methods: 73 healthy normotensive men and women, who are between 18 and 65 years of age, participated in this study. All patients underwent electrocardiography, echocardiography, 24-hour ambulatory blood pressure monitoring and symptom-limited treadmill testing before CIMT and FMD were measured with Doppler ultrasonography. CIMT and FMD values of both groups were statistically compared with each other. Results: Of a total of 73 individuals, 56 were evaluated as the patient group and 17 as the control group. Age, smoking rate, body mass index, resting and maximum blood pressure values, and ascending aorta diameter were significantly higher in the patient group (p=0.02 for smoking, p<0.01 for the rest). Right/left main CIMT, right/left bulbus IMT, and left ventricular diastolic dysfunction was significantly higher in the patient group (p<0.05 for all). In addition, the mean CIMT and mean FMD (%) values were significantly higher and lower, respectively, in the patient group compared to the control group. No difference was observed between the two groups in terms of right/left internal CIMT and passive smoking exposure. In addition, the mean values of CIMT and FMD (%) did not show a statistically significant difference according to hypertensive response stages and gender. Conclusion: CIMT and FMD are significantly associated with EIH. EIH should be evaluated as important risk factor for future hypertension and may cause asymptomatic end-organ damage. It can be easily assessed using CIMT and FMD.

Association between endothelial function and skin advanced glycation end-products (AGEs) accumulation in a sample of predominantly young and healthy adults

BackgroundIn populations with chronic disease, skin autofluorescence (SAF), a measure of long-term fluorescent advanced glycation end-products (AGEs) accumulation in body tissues, has been associated with vascular endothelial function, measured using flow-mediated dilation (FMD). The primary aim of this study was to quantify the relationship between endothelial function and tissue accumulation of AGEs in adults from the general population to determine whether SAF could be used as a marker to predict early impairment of the endothelium.MethodsA cross-sectional study was conducted with 125 participants (median age: 28.5 y, IQR: 24.4–36.0; 54% women). Endothelial function was measured by fasting FMD. Skin AGEs were measured as SAF using an AGE Reader. Participant anthropometry, blood pressure, and blood biomarkers were also measured. Associations were evaluated using multivariable regression analysis and were adjusted for significant covariates.ResultsFMD was inversely correlated with SAF (ρ = -0.50, P < 0.001) and chronological age (ρ = -0.51, P < 0.001). In the multivariable analysis, SAF, chronological age, and male sex were independently associated with reduced FMD (B [95% CI]; -2.60 [-4.40, -0.80]; -0.10 [-0.16, -0.03]; 1.40 [0.14, 2.67], respectively), with the multivariable model adjusted R2 = 0.31, P < 0.001.ConclusionsHigher skin AGE levels, as measured by SAF, were associated with lower FMD values, in a predominantly young, healthy population. Additionally, older age and male participants exhibited significantly lower FMD values, corresponding with compromised endothelial function. These results suggest that SAF, a simple and inexpensive marker, could be used to predict endothelial impairment before the emergence of any structural artery pathophysiology or classic cardiovascular disease risk markers.Trial registrationThe study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12621000821897) and concurrently entered into the WHO International Clinical Trials Registry Platform under the same ID number.

Effects of smoking cessation on endothelial function as assessed by flow-mediated total dilation

BackgroundIn assessing the effects of smoking cessation on endothelial function, low-flow-mediated constriction (L-FMC) may provide complementary information to flow-mediated dilation (FMD). However, the value of flow-mediated total dilation (FMTD), an index that incorporates L-FMC into FMD, remains underreported. We aimed to evaluate the effect of smoking cessation on endothelial function, as assessed by FMD and FMTD, and clarify its associated clinical factors.MethodsWe enrolled 118 consecutive current smokers without previous coronary artery disease (72.9% were men; age: 59 ± 11 years) who underwent smoking cessation treatment. The clinical variables %FMD, %L-FMC, and %FMTD were examined before and 20 weeks after treatment initiation. A multivariate linear regression model was used to investigate the effects of smoking cessation on %FMD and %FMTD and the interaction between smoking cessation and baseline clinical variables.ResultsAfter 20 weeks, 85 smokers (69.4% were men; age: 59 ± 12 years) ceased smoking (abstainers), whereas 33 smokers (81.8% were men; age: 58 ± 11 years) did not (continued smokers). The estimated group differences (abstainers - continued smokers) in changes in the %FMD and %FMTD were 0.77% (95% confidence interval [CI], -0.22–1.77%; p = 0.129) and 1.17% (95% CI, 0.16–2.18%; p = 0.024), respectively. Smoking cessation-associated improvement in %FMTD was greater in women than in men (5.41% [95% CI, 3.15–7.67%] versus 0.24% [95% CI, -0.81–1.28%]; p-value for interaction, < 0.001). Additionally, a greater %FMTD improvement was observed in patients who smoked fewer cigarettes per day (p-value for interaction, 0.042) and those who had a smaller resting baseline lumen diameter (Dbase) (p-value for interaction, 0.023).ConclusionsSmoking cessation was associated with an improvement in %FMTD. Sex, cigarettes smoked per day, and Dbase significantly affected this improvement. The FMTD may help in risk stratification after smoking cessation.

The Association of Systemic Endothelial Dysfunction With Diffuse Diabetic Macular Edema.

Our aim was to assess whether systemic endothelial dysfunction, evaluated non-invasively by flow mediated dilation (FMD), is associated with diabetic macular edema (DME) and to determine if it is further impaired in patients with diffuse-DME. Consecutive patients (n = 84) with type-2 diabetes mellitus (T2DM) and diabetic retinopathy were enrolled. DME was not present in 38 (non-DME) and present in 46 patients; 25 with focal and 21 with diffuse-DME. No differences were detected between DME and non-DME groups regarding the clinical and demographic characteristics, except for the age of T2DM initiation (lower in non-DME). FMD values were significantly impaired in DME compared with non-DME patients, even after adjustment for multiple covariates (3.56 ± 1.03 vs 4.57 ± 1.25%, P = .003). Among DME patients, no differences were found concerning the clinical and demographic data, while FMD levels were significantly lower in diffuse-DME patients, compared with the focal-DME ones, regardless of the impact several confounders (2.88 ± 0.65 vs 4.08 ± 0.95%, P = .002). It is noteworthy that FMD values of non-DME and focal-DME patients did not differ significantly (4.52 ± 1.24 vs 4.21 ± 1.06%, P = .307). Moreover, among DME patients, impaired FMD was an independent predictor of diffuse-DME (odds ratio: 0.06, 95% CI 0.01-0.47, P = .007).

Endothelial Function Correlates With Pulmonary Pressures in Subjects With Clinically Suspected Pulmonary Hypertension

BackgroundImpaired pulmonary circulation hemodynamics are characteristic of pulmonary hypertension. We therefore sought to evaluate possible correlations between endothelial function non-invasively assessed by flow-mediated dilation (FMD) and hemodynamic parameters at right heart catheterization (RHC) in patients with clinically suspected pulmonary hypertension. MethodsConsecutive outpatients with suspected PH were enrolled in the study. In all patients, endothelial function was assessed by FMD and hemodynamic parameters (pulmonary artery pressure (PAP), pulmonary vascular resistances (PVR)) were derived by RHC. ResultsNinety-five consecutive patients with suspected pulmonary hypertension were enrolled in the study (mean age 63±13 years, 58% male) and included in the analysis. FMD values were significantly correlated with systolic (s)PAP levels (r=-0.29, P=0.016); correlation with pulmonary vascular resistance values was of borderline significance (r=-0.21, p=0.78).After multivariable regression analysis including age, gender, TAPSE and peak tricuspid regurgitation velocity (peak-TVR), and FMD, the latter remained significantly correlated with sPAP values (B=-47, p=0.02). After classifying patients according to median levels of peak TRV and FMD into 3 groups (neither, either, or both impaired), progressively increased levels of sPAP, mPAP and PVR were found (P for trend <0.001 in all cases). ConclusionsFMD values were inversely related with sPAP levels in a small population of patients with clinically suspected PH. In combination with peak TRV levels, FMD values non-invasively assessed were predictive of increased sPAP, mPAP, and PVR.

The association between smoking exposure and endothelial function evaluated using flow-mediated dilation values: a meta-analysis

BackgroundTobacco use is recognized as a major cause of cardiovascular disease, which is associated with endothelial dysfunction. Endothelial function is evaluated using flow-mediated dilation (FMD), which is a noninvasive method. This meta-analysis aimed to investigate the association between smoking exposure and endothelial function evaluated using FMD values.MethodsWe searched the PubMed, Embase, Web of Science, and Cochrane Library databases for cohort studies of smokers or passive smokers that used FMD to assess endothelial function. The primary outcome of the study was the change in the rate of FMD. The risk of bias was evaluated using the Cochrane Collaboration tool and Newcastle–Ottawa Scale. Further, the weighted mean difference was used to analyze the continuous data.ResultsOverall, 14 of 1426 articles were included in this study. The results of these articles indicated that smoking is a major cause of endothelial dysfunction and altered FMD; a pooled effect size of − 3.15 was obtained with a 95% confidence interval of (− 3.84, − 2.46). Notably, pregnancy status, Asian ethnicity, or health status did not affect heterogeneity.ConclusionsWe found that smoking has a significant negative impact on FMD, and measures such as medication or education for smoking cessation may improve endothelial function and reduce the risk of cardiovascular disease.Trial RegistrationThe meta-analysis was registered with PROSPERO on April 5th, 2023 (CRD42023414654).

Association of inflammatory markers and ultrasonographic indicators of endothelial (dys)function in humans

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Austrian Science Fund (FWF) Introduction It has been widely known that chronic inflammation is a crucial factor in the process of atherogenesis and atherosclerosis. Also, endothelial dysfunction presents the first and still reversible step of that process.(1) It is a challenge to find a laboratory marker whose levels would be informative about the extent of endothelial dysfunction and atherogenesis in humans. Purpose The aim of the present study was to determine associations between markers of chronic, low-grade inflammation and ultrasonographic indicators of endothelial (dys)function in healthy volunteers (H) and in patients with metabolic syndrome (MS). Methods Any kind of clinically manifest acute inflammatory or infectious disease, as well as chronic inflammatory, autoimmune or malignant disease was an exclusion criterion for participation. Serum levels of C-reactive protein (CRP) were measured using standard clinical chemistry analyser, and serum levels of interleukin-6 (IL-6) using electro-chemiluminescence immunoassay. Blood vessel wall function was quantified as flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD), which were measured automatically and continuously using the ultrasound device with linear probe (10 MHz) and the software for ultrasound blood vessel diameter analysis,(2) following currently valid guidelines.(3,4,5) Results A total of 130 individuals were enrolled in the study (65 H and 65 MS), with a median age of 56 (IQR 50.0, 60.0) years and 47.7% women in each group. CRP and IL-6 levels, although being very low and within the intervals that are considered normal in everyday clinical practice for both groups [CRP - H: 1.2 (0.6, 2.3), MS: 2.4 (1.2, 5.5) μg/mL; IL-6 - H: 2.3 (1.7, 3.0), MS: 4.1 (2.7, 6.8) pg/mL], were significantly higher in the MS compared to H (both p&amp;lt;0.001). The MS group also had significantly lower FMD (p=0.013) and NMD (p=0.033) compared to H. In H, IL-6 levels were significantly negatively correlated with FMD (r=-0.46, p&amp;lt;0.001), but not with NMD; whereas no significant associations of IL-6 levels with FMD or NMD were observed in the MS group. CRP levels were not significantly associated with FMD or NMD in neither the H nor MS group. Conclusion Higher IL-6 serum levels in the absence of acute inflammatory or infectious disease are significantly associated with lower FMD values among individuals with low risk for cardiovascular diseases, who are still considered healthy. Direct correlation is attenuated and lost among individuals with developed clinical signs of metabolic syndrome, probably due to its complex pathophysiology, as well as redundant and interdependent mechanisms contributing to the occurrence of endothelial dysfunction in such an environment. Further investigation on larger cohorts is needed to determine whether IL-6 serum levels could serve as a marker of endothelial dysfunction in individuals without clinically developed traditional risk factors and symptoms of cardiovascular disease.

The Influence of Resting Retrograde Shear Rate on Endothelial Function as Assessed by Flow Mediated Dilation

Shear stress profiles are an important determinant of endothelial function. Unidirectional blood flow enhances mean shear and protects endothelial function, whereas increased retrograde and oscillatory shear favors a proatherogenic environment. In this regard, acutely increasing retrograde shear has been shown to impair endothelial function. Also, previous studies have reported an elevation in retrograde shear in older adults that has been suggested to contribute to impaired endothelial function with age. However, the impact of having elevated retrograde shear at rest on endothelial function remains unclear. Therefore, we aimed to assess the associations between resting shear patterns and endothelial function, as measured by flow-mediated dilation (FMD) in a cohort of young and older adults. We hypothesized that higher retrograde shear rate and oscillatory shear index at rest would be related to a lower FMD value. Method: A total of 60 participants, 30 young adults (24 ± 5 years) and 30 older adults (62 ± 9 years), were studied. Resting brachial artery blood flow was measured using duplex Doppler ultrasound and retrograde shear rate and oscillatory shear index were calculated. Brachial artery FMD was used as a measure of endothelial function. Pearson correlations were used to investigate the associations between FMD, resting shear patterns, and age. Result: FMD was significantly lower in older compared to young adults (4.9 ± 2.7% vs. 7.6 ± 3.2%, p &lt; 0.01). Both retrograde shear rate and oscillatory shear index tended to be greater in older adults (-20.7 ± 15.1 s−1 vs. -15.2 ± 17 s−1, p = 0.062, and 10.7 ± 8% vs. 7.9 ± 8.0%, p = 0.056, respectively). FMD was not correlated with retrograde shear rate (r = -0.18, p = 0.17), or oscillatory shear index (r = -0.21, p = 0.11) in the entire cohort or in the young and older group alone. However, FMD, retrograde shear rate, and oscillatory index were moderately correlated with age: FMD (r = -0.45, p &lt; 0.01), retrograde shear rate (r = -0.32, p = 0.012), and oscillatory shear index (r = 0.33, p &lt; 0.01). Conclusion: These preliminary results suggest that resting retrograde shear and oscillatory shear index are not associated with reduced endothelial function in a cohort of young and old adults. Nevertheless, age-associated reductions in endothelial function and elevated retrograde shear were observed. This project was supported by the College of Nursing and Health Innovation. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Study of Association of Erectile Dysfunction with Metabolic Syndrome and Its Correlation with Endothelial Dysfunction in an Indian Population.

Metabolic syndrome (MS) has emerged as a new health risk, and its associated metabolic derangements have detrimental effects on the cardiovascular system. In recent years, MS has been reported to affect reproductive health in males. It has been reported to be associated with erectile dysfunction (ED) and has been attributed to be due to endothelial dysfunction. Poor endothelial function in ED usually affects small-sized vasculature, so it can be looked at as a predictor for the endothelial dysfunction of macro vasculature. The aim of the present study was to determine the association of ED in patients with MS and to determine its correlation with endothelial dysfunction. It was a hospital-based case-control study in which 120 male patients with MS and 120 age-matched controls were enroled. Demographic profiles, anthropometry, past illnesses, and medical history of patients were obtained. MS was diagnosed according to the International Diabetes Federation (IDF) criteria and was measured using the flow-mediated dilation (FMD) method with the help of ultrasound used to assess endothelial dysfunction. Diagnosis of ED was based on the International Index of Erectile Function (IIEF) scale. The study participants had a mean age of 40.91 ± 11.41 years. The majority of cases (57.5%) had ≤6 months of history of MS. The prevalence of ED was 31.7% in cases compared to 5% in controls, thus showing a significant difference between cases and controls. Mean IIEF scores were significantly lower in cases (18.82 ± 5.59) compared to those in controls (23.00 ± 2.57). A moderate positive and significant correlation was observed between FMD and IIEF scores. With an increasing number of MS components, there was a significant increase in the prevalence of ED. Those with ED had significantly lower mean FMD values (5.1 ± 1.1%) compared to those not having ED (10.9 ± 3.3%). The findings of the present study showed that there is a significant association between ED and MS. We observed that the increase in components of MS increased the prevalence of ED in MS. Endothelial dysfunction measured by FMD was correlated with ED.

Association between triglyceride-glucose index and endothelial dysfunction.

Triglyceride-glucose (TyG) index, a simple surrogate marker for insulin resistance (IR), has been reported as an independent predictor of arterial structural damage and future cardiovascular events. The association between TyG index and endothelial dysfunction remains uncertain. The purpose of this study was to investigate the association between TyG index and endothelial dysfunction. Endothelial dysfunction was measured using flow-mediated dilation (FMD). A total of 840 subjects, who voluntarily accepted FMD measurement at the Health Management Department of Xuanwu Hospital from October 2016 to January 2020, were included in this study. TyG index was calculated as Ln [fasting triglyceride (TG)(mg/dL) × fasting plasma glucose (FPG) (mg/dL)/2]. The mean age was 59.92 ± 10.28 years and 559 (66.55%) participants were male. The TyG index was correlated with FMD values (P = 0.022). Each unit increment in TyG index was associated with lower FMD values (β = -0.330, 95%CI -0.609 to -0.052, P = 0.020) after adjusting for covariates. Age (β = -0.069, 95%CI -0.088 to -0.051, P < 0.001), female (β = 0.592, 95%CI 0.172 to1.012, P = 0.006), smoking (β = -0.430, 95%CI -0.859 to -0.002, P = 0.049) and hypertension (β = -0.741, 95%CI -1.117 to -0.365, P < 0.001) were also independent predictors for endothelial dysfunction. A significant association between the TyG index and endothelial dysfunction was found only in populations younger than 60 years (β = -0.843, 95%CI -1.371 to -0.316, P = 0.002), females (β = -0.612, 95%CI -1.147 to -0.077, P = 0.025), and populations without diabetes mellitus (DM) (β = -0.594, 95%CI -1.042 to -0.147, P = 0.009). Subjects with an elevated TyG index are more likely to have endothelial dysfunction, particularly in populations without DM.

Peripheral vascular function in stroke: systematic review and meta-analysis.

Peripheral vascular dysfunction, measured as flow-mediated dilation (FMD), is present across all phases of stroke recovery and elevates the risk for recurrent cardiovascular events. The objective of this systematic review and meta-analysis was to characterize baseline FMD in individuals' poststroke, with consideration for each phase of stroke recovery. Three databases (PubMed, CINAHL, and Embase) were searched between January 1, 2000 and October 12, 2023 for studies that examined baseline FMD in stroke. Three reviewers conducted abstract and full-text screening, data extraction, and quality assessment. A random effects model was used to estimate FMD across studies. Meta-regression was used to examine the impact of age and time since stroke (acute, subacute, chronic) on FMD. Twenty-eight studies with ischemic and hemorrhagic stroke were included. Descriptive statistics for the demographics and FMD values of each study are presented. For the meta-analysis, average estimate FMD was 3.9% (95% CI: 2.5-5.3%). We report a large amount of heterogeneity (Cochrane's Q P value <0.001, and I2 = 99.6%). Differences in average age and the time poststroke between studies were not significantly associated with differences in FMD values. Despite the large heterogeneity for FMD values across studies, our primary finding suggests that FMD remains impaired across all phases of stroke.NEW & NOTEWORTHY This systematic review and meta-analysis offers invaluable insight into poststroke vascular function. Despite the inherent heterogeneity among the 28 studies analyzed, we report that peripheral vascular dysfunction, as quantified by flow-mediated dilation, exists across all stages of stroke recovery. This finding underscores the importance for interventions that focus on improving vascular health and secondary stroke prevention.

Acute and short-term beetroot juice nitrate-rich ingestion enhances cardiovascular responses following aerobic exercise in postmenopausal women with arterial hypertension: A triple-blinded randomized controlled trial

BackgroundThe increase in blood pressure (BP) levels in the postmenopausal period can be partly explained by the decrease in nitric oxide synthases (NOS). ObjectiveTo investigate the acute and one-week effects of beetroot juice nitrate-rich (BRJ-NO3−rich) ingestion on cardiovascular and autonomic performance in response to submaximal aerobic exercise in postmenopausal women with systemic arterial hypertension (SAH) who are physically inactive. MethodsFourteen postmenopausal women with SAH [mean (SD) age: 59(4) y; BMI (kg/m2): 29.2(3.1)] completed submaximal aerobic exercise bouts after an acute and a one-week intervention with BRJ in a placebo-controlled, randomized, triple-blind, crossover design. Participants ingested either BRJ (800 mg of NO3−) or placebo acutely and drank either BRJ (400 mg of NO3−) or placebo every day for the next six days. After two and ½ hours, they performed a session of aerobic submaximal aerobic exercise, and their systolic BP (SBP) and diastolic BP (DBP), flow-mediated dilation (FMD), heart rate (HR) recovery, and HR variability were measured. ResultsIn the post-exercise recovery period, SBP dropped significantly in the BRJ-NO3−rich group (−9.28 mmHg [95%CI: −1.68 to −16.88] ES: −0.65, p = 0.019) compared to placebo after acute ingestion. The FMD values increased after acute BRJ-NO3−rich on post-exercise (3.18 % [0.36 to 5.99] ES: 0.87, p = 0.031). After the one-week intervention, FMD values were higher in the BRJ-NO3−rich group before (4.5 % [1.62 to 7.37] ES: 1.21, p = 0.005) and post-exercise measurements (4.2 % [1.52 to 6.87] ES: 1.22, p = 0.004) vs. placebo. HRV indices with remarkable parasympathetic modulation to heart recovered faster on the BRJ-NO3−rich group than placebo group. No between-group differences were identified in values of HR post-exercise recovery in the 30s, 60s, 120s, 180s, and 300s. ConclusionsAcute and short-term BRJ-NO3−rich ingestion may enhance cardiovascular and autonomic behavior in response to aerobic exercise in postmenopausal women diagnosed with SAH. Clinical trial registry numberhttps://clinicaltrials.gov/ct2/show/NCT05384340.

Enhanced external counterpulsation improves sleep quality in chronic insomnia: A pilot randomized controlled study

PurposeTo investigate the short-term efficacy of enhanced external counterpulsation (EECP) on chronic insomnia. MethodsThis is a pilot randomized, participant-blind, and sham-controlled study. Forty-six participants with chronic insomnia were randomly assigned in a 1:1 ratio to receive EECP or sham EECP intervention (total of 35 sessions with 45 min each). The primary outcome was Pittsburgh Sleep Quality Index (PSQI). The secondary outcomes included sleep diary, Hospital Anxiety and Depression Scale (HADS), Short-Form Health Survey (SF12), flow mediated dilation (FMD), serum biomarkers of melatonin, cortisol, interleukin-6, and high sensitivity C-reactive protein. Outcomes were assessed after treatment and at 3-month follow-up. ResultsThe PSQI was significantly decreased in both EECP and sham groups after 35-session intervention (13.74 to 6.96 in EECP and 13.04 to 9.48 in sham), and EECP decreased PSQI more than sham EECP (p = 0.009). PSQI in two groups kept improved at 3-month follow-up. After treatment, the total sleep time, sleep efficiency, FMD value and SF12 mental component of EECP group were significantly improved, and group differences were found for these outcomes. At follow-up, total sleep time, sleep efficiency and SF12 mental component of EECP group remained improved, and group difference for SF12 mental component was found. Post-treatment and follow-up HADS-A significantly decreased in both groups, with no differences between groups. Post-treatment serum biomarkers showed no differences within and between groups. LimitationLack of objective sleep measurement. ConclusionEECP could improve sleep quality and mental quality of life in chronic insomnia and the therapeutic effect maintained for 3 months.