Change In Flow-mediated Dilation Research Articles

Effects of Mediterranean Diet on Endothelial Reactivity in Individuals with High Cardiometabolic Risk: A Randomized Controlled Parallel-Group Preliminary Trial.

Endothelial dysfunction is recognized as an early modification involved in the pathogenesis of vascular diseases. Evidence suggests that the Mediterranean Diet (MD) is associated with endothelial function improvement and, in turn, plays an important role in atherosclerosis development and progression. To evaluate both acute and sustained effects of the MD on endothelial function in patients with high cardiometabolic risk. A total of 25 subjects were randomly assigned to either the MD group or the Control Diet (CD) group according to a single-blind, parallel-group study design. Endothelial function was evaluated through non-invasive flow-mediated dilation (FMD) measurements at baseline (T0) and after 8 weeks (Tw8) of the MD or CD intervention, under both 12 h fast condition (fasting) and 2 h post-meal resembling the assigned diet (2 h). Assessments were conducted by a blinded sonographer. FMD at T0-fasting was similar between MD and CD groups (6.11% ± 0.67 vs. 7.90% ± 1.65; p = 0.266). A significant difference in FMD between MD and CD groups was observed at T0-2h (12.14% ± 1.93 vs. 4.01% ± 1.03; p = 0.004), T8w-fasting (9.76% ± 1.18 vs. 5.03% ± 0.89; p = 0.008), and T8w-2h (8.99% ± 1.22 vs. 3.86% ± 0.52; p = 0.003). Oral glucose insulin sensitivity (OGIS) at T0 correlated with FMD percent changes from T0-fasting to T0-2h (r = 0.414, p = 0.044). After adjusting for age, gender, and OGIS, MD was an independent predictor of percent changes in FMD from T0-fasting to T0-2h (β: -0.582, p = 0.003), from T0-fasting to T8w-fasting (β: -0.498, p = 0.013), and from T0-fasting to T8w-2h (β: -0.479, p = 0.018). Adherence to the MD may improve endothelial function in both the short- and medium-term among patients at high cardiometabolic risk.

Comparison of high-intensity interval training and moderate-intensity continuous training on cardiopulmonary function, cardiac autonomic function and vascular function in adolescent boys with obesity: A randomized controlled trial.

Adolescent obesity can impair cardiopulmonary function, vascular elasticity, endothelial function, and vago-sympathetic balance. While moderate-intensity continuous training (MICT) benefits cardiovascular health in obese adolescents, the effects of high-intensity interval training (HIIT) are less understood. We hypothesize that HIIT may be more effective than MICT in improving VO2peak, vascular elasticity, endothelial function, and vago-sympathetic balance in obese adolescent boys. Forty four participants were randomly assigned to the HIIT (10×1-min at 85%-95% peak HR, intersperse with 2-min active recovery at 60%-70% peak HR) or MICT (35min at 65%-75% peak HR) for an 8-week program. The primary outcome measured was the change in VO2peak with secondary outcomes including brachial-ankle pulse wave velocity (baPWV), flow-mediated dilation (FMD), and heart rate variability (HRV). Forty four adolescent boys with obesity (age, 14±1years old, body mass index, 31.6±1.3kg/m2) were enrolled and 43 (97.73%) completed the 8-week exercise. No significant difference of VO2peak was found between the HIIT and MICT group (p=0.243). There was no significant difference of baPWV between the groups (p=0.789). Change in FMD% was significantly higher in the HIIT group compared to the MICT group (p<0.001). The Change in HRV-high frequency (HRV-HF; p=0.009) and HRV-low frequency/high frequency (HRV-LF/HF; p=0.035) was significantly higher in the HIIT group compared to the MICT group. Among adolescent boys with obesity, 8-week HIIT and MICT had similar effects on improving VO2peak. HIIT may be superior to MICT to improve endothelial function and vago-sympathetic balance.

Age and sex differences in the effects of short- and long-term exposure to air pollution on endothelial dysfunction

Abstract Background Endothelial dysfunction is an integrated index of risk factor burden and a marker of atherosclerotic cardiovascular disease. Air pollution is widely acknowledged as a significant non-traditional risk factor for cardiovascular disease. However, the impact of air pollutants at varying concentrations and exposure durations on endothelial function in different populations remains unclear. Purpose We aimed to use brachial artery flow-mediated dilatation (FMD) to identify demographic differences in the effects of short- and long-term exposure to air pollution on endothelial dysfunction. Methods We measured FMD in 850 participants from October 2016 to January 2020. Location-specific concentrations of fine particulate matter &amp;lt;2.5 μm aerodynamic diameter (PM2.5), inhalable particulate matter &amp;lt;10 μm aerodynamic diameter (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) measured by fixed ambient air monitoring stations were collected for short- and long-term exposure assessment. We used the moving average 7- and 14-day exposures before the date of FMD measurements to estimate the short-term exposure effects and the moving average 12-month exposures before the date of FMD measurements to estimate the long-term exposure effects. Multiple linear regression models and restricted cubic splines were used to assess the associations before and after stratified by age and sex. Results This study eventually included 828 participants [551 (66.5%) younger than 65 years and 553 (66.8%) men]. Each 10 μg/m³ increase in 12-month exposure to PM10 and NO2 was significantly and linearly associated with -0.20% (95% CI: -0.37 to -0.03) and -0.58% (95% CI: -0.99 to -0.18) changes in FMD in all participants. 12-month exposure to gaseous pollutants was also significantly but nonlinearly associated with lower FMD. 7-day exposure to Quartile 4 of SO2 was significantly associated with a 0.70% decrease in FMD compared to Quartile 1 (β = -0.70, 95% CI: -1.40 to -0.008). No relationships were observed between 7- and 14-day exposure to PM2.5, PM10, NO2, CO, and endothelial dysfunction. Although interaction effects were limited to SO2 and sex, significant associations with different air pollutants were only found in men and those younger than 65 years after stratified. Conclusions Long-term exposure to air pollution is strongly associated with decreased endothelial function, and susceptibility to air pollution varies significantly with age and sex. Further identification of different susceptible populations and proactive measures to mitigate air pollution may be beneficial in reducing the burden of cardiovascular disease.

Effects of Resistance Training on Selected Hemodynamic and Functional Factors in Older Men

Objectives Changes in hemodynamic factors such as blood pressure, rate of pressure product (RPP) and flow mediated dilation (FMD), are the most important cardiovascular changes in older age. This study aims to investigate the effect of resistance training on some hemodynamic and functional factors in older men. Methods &amp; Materials In this quasi-experimental study, 24 older men were selected from among 100 older residents of Kahrizak Nursing Home in Alborz Province, Iran and were randomly divided into control and training groups. Before and after eight weeks of resistance training, mean blood pressure (MBP), RPP, FMD, hand grip strength and timed up &amp; go (TUG) time were measured. The difference in the variables between the two groups was analyzed by independent and paired t-test using SPSS software version 25. The significance level was set at 0.05 Results The mean of age of participants was 67.75 years. Decreased MBP (P=0.027), increased FMD changes (P=0.022), decreased RPP (P=0.023), increased hand grip strength (P=0.019), and decreased TUG time (P=0.032) were reported in the training group. Conclusion Resistance training can reduce the load on the cardiovascular system by improving hemodynamic factors and possibly prevent the occurrence of cardiovascular diseases related to older age. Therefore, resistance training with sufficient intensity can be considered as a supplement to aerobic training in old age.

Exploring the Impact of Inhaled Corticosteroids on Endothelial Function in Chronic Obstructive Pulmonary Disease Patients Undergoing Pulmonary Rehabilitation.

Background: Chronic obstructive pulmonary disease (COPD) is associated with subclinical atherosclerosis and endothelial dysfunction, which can be assessed non-invasively through flow-mediated dilation (FMD). In this study, we evaluated the potential impact of inhaled corticosteroid (ICS) therapy on FMD of COPD patients undergoing pulmonary rehabilitation (PR). Methods: Medical records of COPD patients undergoing FMD assessment upon admission to our Pulmonary Rehabilitation Unit were reviewed in this retrospective post hoc analysis. Results: A total of 46 patients with COPD (median age 71.5 years, 28.3% postmenopausal females) were included in the final analysis. Among these, 27 participants were currently receiving ICS therapy, while 19 were not. At baseline, the two groups showed no difference in the main clinical and functional variables. Similarly, no significant difference was observed in vascular reactivity parameters, with a median FMD of 3.12% (IQR: 2.23-4.45) in ICS users and 3.39% (IQR: 2.45-4.08) in ICS nonusers (p = 0.544). After PR, a significant improvement in the main rehabilitation and patient-reported outcomes was observed in all groups, with a significant improvement in FMD documented in both patients treated with steroids (from 3.12%; IQR: 2.23-4.45 to 4.77%; IQR: 3.25-5.63, p = 0.022) and in those who were not (from 3.39%; IQR: 2.45-4.08 to 5.04%; IQR: 3.98-6.06, p = 0.005). FMD changes were of comparable magnitude among groups. Conclusions: Our preliminary findings do not indicate a significant impact of medications containing ICS on the endothelial function of COPD patients, suggesting that the potential beneficial effect of PR on this surrogate marker of cardiovascular risk is independent of inhaled therapy.

Age and sex differences in the effects of short- and long-term exposure to air pollution on endothelial dysfunction

BackgroundThe effects of air pollution on endothelial function remain unclear across populations. We aimed to use brachial artery flow-mediated dilatation (FMD) to identify demographic differences in the effects of air pollution exposure on endothelial dysfunction.MethodsWe measured FMD in 850 participants from October 2016 to January 2020. Location-specific concentrations of fine particulate matter < 2.5 μm aerodynamic diameter (PM2.5), inhalable particulate matter < 10 μm aerodynamic diameter (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) measured by fixed ambient air monitoring stations were collected for short- and long-term exposure assessment. Multiple linear regression models and restricted cubic splines were used to assess the associations before and after stratification by age and sex.ResultsThis study eventually included 828 participants [551 (66.5%) younger than 65 years and 553 (66.8%) men]. Each 10 µg/m3 increase in 7-day exposure to PM2.5 and PM10 was significantly linearly associated with a 0.07% (β = -0.07, 95% CI: -0.13 to -0.004) and 0.05% (β = -0.05, 95% CI: -0.10 to -0.004) decrease in FMD in the fully adjusted model. After full adjustment, long-term exposure to all air pollutants was significantly associated with impaired FMD. Each 10 µg/m3 increase in long-term exposure to PM2.5 and PM10 was significantly associated with a -0.18% (95% CI: -0.34 to -0.03) and − 0.23% (95% CI: -0.40 to -0.06) change in FMD, respectively. After stratification, the associations of lower FMD with long-term exposure to PM2.5, PM10, SO2, NO2, and CO significantly persisted in men and participants younger than 65 years instead of women or older participants. For short-term exposure, we observed differences consistent with long-term exposure and a stronger effect of 7-day exposure to SO2 in men due to a significant interaction effect.ConclusionShort- and long-term exposure to different air pollutants are strongly associated with decreased endothelial function, and susceptibility to air pollution varies significantly with age and sex.

Effect of Incorporating 1 Avocado per Day Versus Habitual Diet on Vascular Function in Adults With Abdominal Obesity: An Ancillary Study of HAT, a Randomized Controlled Trial.

Abdominal obesity is associated with endothelial dysfunction and poorer vascular health. Avocado consumption improves postprandial endothelial function; however, the longer-term effects remain unclear. It was hypothesized that the daily addition of 1 avocado to a habitual diet for 6 months would improve flow-mediated dilation (FMD) and carotid-femoral pulse wave velocity in individuals with abdominal obesity (waist circumference ≥35 in for women, ≥40 in for men), compared with a habitual diet low in avocados. HAT (Habitual Diet and Avocado Trial) was a multicenter, randomized, controlled, parallel-arm study that investigated the health effects of adding 1 avocado per day to a habitual diet in individuals with abdominal obesity. At the Pennsylvania State University, University Park study center (n=134; age, 50 ± 13 years; women, 78%; body mass index, 32.6 ± 4.8 kg/m2), markers of vascular function were measured, including endothelial function, assessed via brachial artery flow-mediated dilation, and arterial stiffness, assessed via carotid-femoral pulse wave velocity. Between-group differences in 6-month change in flow-mediated dilation and carotid-femoral pulse wave velocity were assessed using independent t tests. Prespecified subgroup analyses were conducted using linear regression. No significant between-group differences in flow-mediated dilation (mean difference=-0.62% [95% CI, -1.70 to 0.46]) or carotid-femoral pulse wave velocity (0.25 m/s [95% CI, -0.13 to 0.63]) were observed. Results of the subgroup analyses were consistent with the primary analyses. Longer-term consumption of 1 avocado per day as part of a habitual diet did not improve measures of vascular function compared with a habitual diet low in avocados in individuals with abdominal obesity. URL: https://www.clinicaltrials.gov; Unique identifier: NCT03528031.

Effect of low-volume combined aerobic and resistance high-intensity interval training on vascular health in people with type 2 diabetes: a randomised controlled trial

PurposeWe compared the effects of low-volume combined aerobic and resistance high-intensity interval training (C-HIIT), combined moderate-intensity continuous training (C-MICT) and waitlist control (CON) on vascular health after 8-weeks of supervised training, and an additional 10-months of self-directed training, in adults with type 2 diabetes (T2D).MethodsSixty-nine low active adults with T2D were randomised to 8-weeks of supervised C-HIIT (3 times/week, 78-min/week), C-MICT (current exercise guidelines, 4 times/week, 210-min/week) or CON. CON underwent usual care for 8-weeks before being re-randomised to C-HIIT or C-MICT. This was followed by 10-months of self-directed training for participants in C-HIIT and C-MICT. Vascular outcomes were evaluated at baseline, 8-weeks, and 12-months.ResultsAfter 8-weeks, supervised C-HIIT significantly improved relative flow-mediated dilation (FMD) compared with CON (mean difference [MD] 0.8% [0.1, 1.4], p = 0.025). Although not significantly different from CON, the magnitude of change in relative FMD following 8-weeks of supervised C-MICT was similar (MD 0.8% [–0.1, 1.7], p = 0.080). There were no differences in haemodynamic indices, carotid-femoral pulse wave velocity (cfPWV), or aortic reservoir pressure between groups at 8-weeks. After 12-months, there was a significant reduction in haemodynamic indices (time effect, p < 0.05) for both C-HIIT and C-MICT, with no between-group difference. The reduction in cfPWV over 12-months was significantly greater in C-MICT than C-HIIT (group × time effect, p = 0.018). There was no difference in FMD over time or between groups at 12-months.ConclusionsShort-term supervised C-HIIT and C-MICT both increased brachial artery FMD compared with CON. Long-term C-HIIT and C-MICT were beneficial for improving haemodynamic indices, but not brachial artery FMD. C-MICT was superior to C-HIIT for improving cfPWV at 12-months.Trial Registration: Australian New Zealand Clinical Trials Registry Identifier ACTRN12615000475549.

Acute and Chronic Endothelial Responses to Home-based High Intensity Interval Training in Healthy Older Adults

Advancing age is associated with endothelial dysfunction, a key early event in atherosclerosis development. Endurance exercise is recommended for cardiovascular disease prevention and some studies report endurance exercise training has beneficial effects on endothelial function in older adults. We have recently developed a supervised home-based exercise intervention using high intensity interval training on an all-extremity non-weight-bearing ergometer (HIIT-ANE). We tested the hypotheses that in healthy older adults: 1) endothelial function is improved in response to chronic HIIT-ANE, 2) the acute endothelial responses to HIIT-ANE are different in the trained and untrained states, and 3) the acute and chronic endothelial responses to HIIT-ANE are related. We assessed flow-mediated dilation (FMD), a measure of endothelial function, using brachial artery ultrasonography in twenty healthy sedentary older adults (age: 66±1, means ± SE; 11 postmenopausal women and 9 men). FMD was assessed: 1) in response to chronic HIIT-ANE (at baseline, after 8 weeks of normal lifestyle (control condition), and after 8 weeks of home-based HIIT-ANE) and 2) in response to a single session of HIIT-ANE (at pre-exercise, end of exercise and 1-hr and 24-hrs post-exercise), in the untrained and trained states. Following 8 weeks of HIIT-ANE, FMD was improved compared with baseline (3.39±0.30 vs. 4.18±0.46 %, P=0.005), but was not significantly changed from pre- to post-HIIT-ANE (3.68±0.44 vs. 4.18±0.46 %, P=0.3) or from baseline to post-control (3.39±0.30 vs. 3.68±0.44 %, P=0.4). In the untrained state, FMD was attenuated in response to a single bout of HIIT-ANE from pre- to 1-hr post-exercise (4.15±0.35 vs. 2.92±0.36 %, P=0.0004) and returned to pre-exercise level in 24-hrs post-exercise (4.15±0.35 vs. 3.98±0.40 %, P=1). In the trained state, the acute FMD response to HIIT-ANE was similar to the untrained state (P=0.6 for training state × time). The chronic change in FMD was inversely related with the acute change in FMD in the trained state (ρ=-0.70; p&lt;0.001), but not in the untrained state (ρ=-0.12; P=0.6). Biological sex did not significantly influence the acute or chronic FMD responses to HIIT-ANE (P≥0.1). In healthy older adults: 1) FMD is improved following 8-weeks of home-based remotely supervised HIIT-ANE compared to baseline, 2) FMD is attenuated and normalized within 24 hours of a single session of HIIT-ANE, and 3) chronic changes in FMD are related to acute changes in FMD. This work was supported by the National Institute of Aging grant AG063143. 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.

Comparison of flow-mediated dilation (FMD) of the brachial artery in normotensive versus preeclamptic pregnant females.

Flow-mediated dilation (FMD) of the brachial artery is an ultrasonography test that assesses the endothelial response to reactive hyperemia. The aim of this study was to assess the changes in FMD in preeclamptic pregnant patients and compare them with normotensive pregnant females. An analytical cross-sectional comparative study was conducted in the Department of Obstetrics and Gynaecology at King George's Medical University (KGMU) after obtaining ethical approval. A total of 110 normotensive and 100 preeclamptic patients were recruited for the study. Using a Toshiba Ultrasound Machine with a 7-12 MHz probe, the baseline diameter of the brachial artery D1 was measured. Afterward, the cuff of the sphygmomanometer was placed distally on the forearm and it was inflated up to ≥250 mm of Hg pressure and later slowly deflated. At 90th seconds after cuff deflation, the mean of three measurements of vessel caliber (D2) was obtained. The FMD% was obtained by the following equation: FMD (%) = [(D2 - D1)/D1] ×100, where D1 = basal diameter and D2 = post-occlusion diameter. All patients were followed till delivery for maternofetal outcome. FMD% was significantly lower in the preeclampsia group, and it went on decreasing with increasing severity of preeclampsia. At the cutoff of 9.4 for FMD%, its sensitivity for the prediction of preeclampsia was 65.3%, specificity was 89.3%, positive predictive value (PPV) was 94%, and negative predictive value (NPV) was 50%. FMD is a noninvasive test, and it gets decreased before clinical signs of preeclampsia, so it can be used as a predictor of preeclampsia.

Endothelial Dysfunction in Children With Nephrotic Syndrome: A Cross-Sectional Study.

Background Children with nephrotic syndrome (NS) have a higher risk of cardiovascular morbidity. Studies on the evaluation of arterial stiffness and endothelial function and its predictive risk factors in these children are limited. Objective The primary objective of the study was to determine arterial stiffness by measuring carotid intimal medial thickness, flow-mediated dilatation, and physiological parameters in children with nephrotic syndrome to predict the risk of premature atherosclerosis as compared to controls. Participants A total numberof 33 children with NS in the age group of 2-14 years in remission and 39 healthy controls were enrolled in the study. Out of 33 children with nephrotic syndrome, five were infrequently relapsing NS, eight were frequently relapsing, 16 were steroid dependent, and four were steroid-resistant NS. Intervention Relevant history, physical examination, anthropometric measurements, and laboratory investigations were done. Carotid intimal medial thickness (cIMT), flow-mediated dilatation (FMD), and other physiological parameters were measured in both children with NS and control groups. Outcome Carotid intimal medial thickness (cIMT), flow-mediated dilatation (FMD), and other physiological parameters were compared between children with NS and healthy controls for detecting arterial stiffness and endothelial dysfunction. Results Dyslipidaemia was seen in more than 50% of children during remission. There was neither significant difference in mean cIMT in the common carotid artery nor FMD between the control and study groups. There was a trend of lower Reactive Hyperemia Index (RHI) in children with NS. Conclusion Dyslipidemia persists even during the remission phase in NS. No statistically significant difference is observed in cIMT and percentage proportionate change in FMD in both the study and control groups. Nevertheless, RHIis notably lower in children with NS. These findings need further validation in future studies.

Effects of Oxygen Prebreathing on Bubble Formation, Flow-Mediated Dilatation, and Psychomotor Performance during Trimix Dives.

Introduction: This research was performed to examine the effects of air and oxygen prebreathing on bubble formation, flow-mediated dilatation, and psychomotor performance after scuba dives. Methods: Twelve scuba divers performed two dives using a gas mixture of oxygen, nitrogen, and helium (trimix). In a randomized protocol, they breathed air or oxygen 30 min before the trimix dives. Venous bubble formation, flow-mediated dilatation, and psychomotor performance were evaluated. The participants solved three psychomotor tests: determining the position of a light signal, coordination of complex psychomotor activity, and simple arithmetic operations. The total test solving time, minimum single-task solving time, and median solving time were analyzed. Results: The bubble grade was decreased in the oxygen prebreathing protocol in comparison to the air prebreathing protocol (1.5 vs. 2, p < 0.001). The total test solving times after the dives, in tests of complex psychomotor coordination and simple arithmetic operations, were shorter in the oxygen prebreathing protocol (25 (21-28) vs. 31 (26-35) and 87 (82-108) vs. 106 (90-122) s, p = 0.028). Conclusions: In the oxygen prebreathing protocol, the bubble grade was significantly reduced with no change in flow-mediated dilatation after the dives, indicating a beneficial role for endothelial function. The post-dive psychomotor speed was faster in the oxygen prebreathing protocol.

Smoking Cessation Is Associated With Short-Term Improvement of Vascular Health in a Cohort of People Living With HIV in Rio de Janeiro, Brazil

Smoking is highly prevalent in people living with HIV/AIDS (PLHA), leading to detrimental effects in different tissues. We examined the effects of nicotine replacement therapy (NRT) on smoking cessation and vascular health. From December 2019 to October 2021, we prospectively enrolled PLHA who were actively smoking. The primary outcome was endothelial function measured by brachial artery flow-mediated dilatation (FMD). We evaluated the percent change in FMD compared to the baseline measure (Δ%FMD) to detect improvements among participants who quit smoking. To confirm the results, we used linear regression models to account for classical cardiovascular (CV) confounders. We included 117 participants with median age of 45.5 years (IQR= 36.4-54.8); 22 (20.4%) had hypertension, 9 (8.3%) had diabetes, almost half were smoking 20+ cigarettes/day (41.7%). After 12 weeks 30.76% participants quit smoking. Comparison of Δ%FMD change from baseline to week 12 showed that among participants adherent to therapy, there has been an increase in Δ%FMD when compared to those who relapsed (1.17% [0.29-2.98] vs - 0.19% [-1.95-0.91], p<0.001). After adjustment for CV factors, multiple linear regression showed that Δ%FMD in participants who quit smoking presented a 2.54 mean increase in comparison to those who continued smoking (p=0.007). In conclusion, this study provides evidence that a strategy of NRT and counseling is modestly effective for smoking cessation in PLHA and improves vascular health in a short period of time. This reinforces the importance of the widespread anti-tobacco programs in HIV clinics and the expected impact lowering the incidence of future cardiovascular events

Impairment of Endothelial Function by Aerosol From Marijuana Leaf Vaporizers.

Marijuana leaf vaporizers, which heat plant material and sublimate Δ-9-tetrahydrocannabinol without combustion, are popular alternatives to smoking cannabis that are generally perceived to be less harmful. We have shown that smoke from tobacco and marijuana, as well as aerosol from e-cigarettes and heated tobacco products, impair vascular endothelial function in rats measured as arterial flow-mediated dilation (FMD). We exposed 8 rats per group to aerosol generated by 2 vaporizer systems (Volcano and handheld Yocan) using marijuana with varying Δ-9-tetrahydrocannabinol levels, in a single pulsatile exposure session of 2 s/min over 5 minutes, and measured changes in FMD. To model secondhand exposure, we exposed rats for 1 minute to diluted aerosol approximating release of uninhaled Volcano aerosol into typical residential rooms. Exposure to aerosol from marijuana with and without cannabinoids impaired FMD by ≈50%. FMD was similarly impaired by aerosols from Yocan (237 °C), and from Volcano at both its standard temperature (185 °C) and the minimum sublimation temperature of Δ-9-tetrahydrocannabinol (157 °C), although the low-temperature aerosol condition did not effectively deliver Δ-9-tetrahydrocannabinol to the circulation. Modeled secondhand exposure based on diluted Volcano aerosol also impaired FMD. FMD was not affected in rats exposed to clean air or water vapor passed through the Volcano system. Acute direct exposure and modeled secondhand exposure to marijuana leaf vaporizer aerosol, regardless of cannabinoid concentration or aerosol generation temperature, impair endothelial function in rats comparably to marijuana smoke. Our findings indicate that use of leaf vaporizers is unlikely to reduce the vascular risk burden of smoking marijuana.

Effect of Resveratrol on Endothelial Function in Patients with CKD and Diabetes: A Randomized Controlled Trial.

Patients with CKD and diabetes are at higher risk of developing cardiovascular disease, in part, because of impaired endothelial function. Cardioprotective compounds such as resveratrol could improve endothelial function and attenuate the cardiovascular burden in patients with CKD and diabetes. We hypothesized that resveratrol supplementation would improve endothelial function in patients with CKD and diabetes. Twenty-eight adults aged 68±7 years (84% men) with stage 3 CKD and diabetes were enrolled in a randomized, double-blind, placebo-controlled, crossover study to investigate the effects of 6-week resveratrol supplementation (400 mg/d) on endothelial function. Endothelial function was determined through brachial artery flow-mediated dilation. The mean values for eGFR and hemoglobin A 1c were 40±9 ml/min per 1.73 m 2 and 7.36%±0.72%, respectively. Compared with placebo, resveratrol supplementation increased flow-mediated dilation (ratio of geometric mean changes and 95% confidence interval for between-group comparisons, 1.43 (1.15 to 1.77); P value = 0.001). eGFR, hemoglobin A 1c , BP, and nitroglycerin-mediated dilation were unchanged with resveratrol or placebo ( P = 0.15), suggesting the observed change in flow-mediated dilation was likely independent of changes in traditional cardiovascular risk factors. Resveratrol supplementation improved endothelial function in patients with CKD and diabetes. Resveratrol and Vascular Function in CKD, NCT03597568 . This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_11_20_CJN0000000000000337.mp3.

The effects of water-based circuit exercise training on vascular function in people with coronary heart disease.

Impaired endothelial function in people with coronary heart disease (CHD) is associated with increased mortality. Water immersion can increase peripheral artery shear stress which may provide an additional stimulus to the endothelium during exercise. This study compared the effects of water-based circuit exercise training (WEX) and gym-based circuit exercise training (GEX) on vascular function in people with stable CHD. Participants were randomised to 12 weeks of WEX (n=20), GEX (n=20) or a control group (usual activities; n=12). Endothelium-dependent flow-mediated dilation (FMD) and glyceryl trinitrate-mediated dilation (GTN) of the brachial artery were assessed pre- and post-intervention. FMD increased following WEX [4.0% (3.0-5.1%) to 5.3% (4.1-6.5%); p=0.016], but was unchanged following GEX [4.9% (3.8-5.9%) to 5.0% (3.8-6.1%); p=0.822]. There were no between-group differences in the change in FMD and no significant changes in GTN-mediated dilation percentage. Triglycerides decreased following GEX [1.2 mmol.L-1 (1.0-1.4 mmol.L-1) to 1.0 mmol.L-1 (0.8-1.3 mmol.L-1); p=0.022], but there were no further differences in lipid profiles. WEX improved endothelial function of the brachial artery in people with stable CHD, suggesting that WEX is an effective alternative to gym-based exercise in people living with CHD, which may specifically address vascular health.

Subthalamic deep brain stimulation improves vascular endothelial function in Parkinson's disease

ObjectivesVascular health (white matter change, vascular risk factor, angiogenesis, microvascular alteration) is associated with clinical progression or levodopa-induced dyskinesia in PD. Vascular endothelial function is known to reflect the earliest vascular change. While DBS can improve motor and non-motor symptoms, the effect of DBS on vascular endothelial function is unknown. Thus, we aimed to investigate whether DBS surgery could impact vascular endothelial function in PD. MethodA total of 20 PD patients were recruited. Vascular endothelial function was evaluated with flow-mediated dilation (FMD). FMD was investigated before and after one year of DBS surgery. ResultsFMD improved (6.01 ± 1.58 to 6.84 ± 1.57, p = 0.027). While the level of homocysteine slightly decreased (13.8 ± 4.1 to 13.0 ± 3.2, p = 0.05), there was no significant correlation between FMD changes and homocysteine levels (r = 0.42, p = 0.065). FMD change was associated with baseline age (r = −0.59, p = 0.006) but not with disease duration (p = 0.73), baseline UPDRS III (p = 0.81), change of UPDRS III and dyskinesia, and LEDD change (p = 0.94). Multivariate linear regression analysis revealed that only age (B = −0.139; p = 0.024) was significantly and inversely correlated with the change of FMD. ConclusionsWe found that STN-DBS improves vascular endothelial function in PD. Further studies are needed to clarify the exact pathogenesis and clinical implication of beneficial effects on vascular endothelial dysfunction in PD.

Impact of bariatric surgery on carotid intima-media thickness, flow-mediated dilation, and nitrite-mediated dilation: a systematic review and meta-analysis.

Obesity is considered one of the independent risk factors for atherosclerosis and is strongly correlated with cardiovascular morbidity and mortality. Previous studies showed carotid intima-media thickness (CIMT), flow-mediated dilation (FMD), and nitrite-mediated dilatation (NMD) are reliable non-invasive markers of arterial damage and dysfunction. The aim of this study was to evaluate the effect of bariatric surgery on CIMT, FMD, and NMD markers in patients with obesity. A systematic search was performed in the PubMed, Embase, Scopus, and Web of Science databases until May 2022. All the English-published studies on the effect of bariatric surgery on CIMT, FMD, and NMD were included. A quantitative meta-analysis was performed, as well as subgroup analyses for the type of procedure and duration of follow-up. Meta-analysis of 41 studies with 1639 patients showed CIMT was significantly reduced by .11 mm after bariatric surgery (95% CI, -.14 to -.08; P < .001; mean follow-up = 10.8 mo). The pooled analysis of 23 studies with 1106 patients showed an increase of FMD by 4.57% after bariatric surgery (95% CI, 2.69-6.44; P < .001; mean follow-up = 11.5 mo). The results of a pooled analysis of 12 studies with 346 patients showed a significant increase of NMD by 2.46% after bariatric surgery (95% CI, .99-3.94; P < .001; mean follow-up = 11.4 mo). The random effect meta-regression demonstrated that baseline CIMT and FMD significantly affect the changes in CIMT and FMD. This meta-analysis showed bariatric surgery can improve CIMT, FMD, and NMD markers in patients with obesity. These improvements show the known effect of metabolic surgery in decreasing cardiovascular risk.

A double-blind, randomised, placebo-controlled parallel study to investigate the effect of sex and dietary nitrate on COVID-19 vaccine-induced vascular dysfunction in healthy men and women: protocol of the DiNOVasc-COVID-19 study

BackgroundCardiovascular events, driven by endothelial dysfunction, are a recognised complication of COVID-19. SARS-CoV-2 infections remain a persistent concern globally, and an understanding of the mechanisms causing endothelial dysfunction, particularly the role of inflammation, nitric oxide, and whether sex differences exist in this response, is lacking. We have previously demonstrated important sex differences in the inflammatory response and its impact on endothelial function and separately that the ingestion of inorganic nitrate can protect the endothelium against this dysfunction. In this study, we will investigate whether sex or a dietary inorganic nitrate intervention modulates endothelial function and inflammatory responses after the COVID-19 vaccine.MethodsDiNOVasc-COVID-19 is a double-blind, randomised, single-centre, placebo-controlled clinical trial. A total of 98 healthy volunteers (49 males and 49 females) will be recruited. Participants will be randomised into 1 of 2 sub-studies: part A or part B. Part A will investigate the effects of sex on vascular and inflammatory responses to the COVID-19 vaccine. Part B will investigate the effects of sex and dietary inorganic nitrate on vascular and inflammatory responses to the COVID-19 vaccine. In part B, participants will be randomised to receive 3 days of either nitrate-containing beetroot juice (intervention) or nitrate-deplete beetroot juice (placebo). The primary outcome for both sub-studies is a comparison of the change in flow-mediated dilatation (FMD) from baseline after COVID-19 vaccination. The study has a power of > 80% to assess the primary endpoint. Secondary endpoints include change from baseline in inflammatory and leukocyte counts and in pulse wave analysis (PWA) and pulse wave velocity (PWV) following the COVID-19 vaccination.DiscussionThis study aims to evaluate whether sex or dietary influences endothelial function and inflammatory responses in healthy volunteers after receiving the COVID-19 vaccine.Trial registrationClinicalTrials.gov NCT04889274. Registered on 5 May 2023. The study was approved by the South Central – Oxford C Research Ethics Committee (21/SC/0154).

Effect of Aortic Valve Opening Pattern on Endothelial Function After Continuous-Flow Left Ventricular Assist Device Implantation.

This study aimed to evaluate the effects of aortic valve opening patterns on endothelial functions in patients undergoing continuous-flow left ventricular assist device (CF-LVAD) implantation. This study included 43 patients who underwent CF-LVAD implantation and 35 patients with heart failure reduced ejection fraction (HFrEF; control group). The CF-LVAD group was divided into three subgroups based on aortic valve opening patterns: open with each beat, intermittently opening, and not opening groups. Flow-mediated dilatation (FMD) and pulsatility index (PI) were compared before and 3 months after CF-LVAD implantation. Cardiopulmonary exercise test (CPET) and 6 minute walk test (6-MWT) scores were measured at baseline and follow-up in the CF-LVAD group. The mean FMD and PI of patients in the CF-LVAD group reduced 3 months after implantation. Patients with intermittently opening and not opening aortic valves had worse endothelial function at follow-up. Before and 3 months after implantation FMD% did not significantly differ in patients whose aortic valves were open with each beat (4.72 ± 1.06% vs. 4.67 ± 1.16%, p = 0.135). Pulsatility index changes paralleled FMD changes. Cardiopulmonary exercise test and 6-MWT scores improved after implantation but without significant differences between subgroups. Maintaining normal aortic valve function after CF-LVAD implantation may reduce endothelial dysfunction; however, larger studies are needed for long-term clinical effects.