Change In Flow-mediated Dilation Research Articles

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.

We 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). Sixty-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. After 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. Short-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. Australian New Zealand Clinical Trials Registry Identifier ACTRN12615000475549.

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

ABSTRACT Introduction: 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. Methods: 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. Results: 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%. Discussion: 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 .

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.

Acute daily exposure to ambient air pollution impairs endothelium-dependent vasodilator responses in young, healthy individuals.

Exposure to ambient air pollution influences cardiovascular (CV) morbidity and mortality. The differential effects of changing particulate or gaseous air pollution on endothelial function in young healthy individuals remain unclear. The aim of this study was to evaluate the relationships between exposures to different pollutants and vascular function in a group of 39 young (33±11 years old) subjects with low CV risk. Flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) were performed, when air pollution reached highest levels (heating period) and repeated in a subgroup of 18 participants a few months later (just before the heating period starts). Daily mean concentrations of PM2.5 and PM10 were inversely correlated with FMD, and this relationship remained significant after adjusting for factors known to affect vascular dysfunction. Endothelial function did not differ between the two time points studied. However, we observed a strong inverse association between the change in the concentration of particulate matter (deltaPM2.5 and deltaPM10) and the change in FMD (deltaFMD) between the two visits (R= -0.65, p= 0.02; R= -0.64, p= 0.02, respectively). In summary, we provide evidence that the concentration of PM2.5 and PM10, but not SO2, NO, NO2, CO, or O3 is associated with impaired endothelial function in young, healthy individuals.

Transiently impaired endothelial function during thyroid hormone withdrawal in differentiated thyroid cancer patients.

Endothelial dysfunction, which was associated with chronic hypothyroidism, was an early event in atherosclerosis. Whether short-term hypothyroidism following thyroxine withdrawal during radioiodine (RAI) therapy was associated with endothelial dysfunction in patients with differentiated thyroid cancer (DTC) was unclear. Aim of the study was to assess whether short-term hypothyroidism could impair endothelial function and the accompanied metabolic changes in the whole process of RAI therapy. We recruited fifty-one patients who underwent total thyroidectomy surgery and would accept RAI therapy for DTC. We analyzed thyroid function, endothelial function and serum lipids levels of the patients at three time points: the day before thyroxine withdrawal(P1), the day before 131I administration(P2) and 4-6 weeks after RAI therapy(P3). A high-resolution ultrasound named flow-mediated dilation (FMD) was used to measure endothelial function of the patients. We analyzed the changes of FMD, thyroid function and lipids at three time points. FMD(P2) decreased significantly compared to FMD(P1) (P1vsP2, 8.05 ± 1.55vs 7.26 ± 1.50, p<0.001). There was no significant difference between FMD(P3) and FMD(P1) after restoring TSH (thyroid stimulating hormone) suppression therapy (P1 vs P3, 8.05 ± 1.55 vs 7.79 ± 1.38, p=0.146). Among all parameters, the change of low-density lipoprotein (ΔLDL) was the only factor correlated negatively with the change of FMD (ΔFMD) throughout the RAI therapy process (P1-2, r=-0.326, p=0.020; P2-3, r=-0.306, p=0.029). Endothelial function was transiently impaired in DTC patients at short-term hypothyroidism state during the RAI therapy, and immediately returned to the initial state after restoring TSH suppression therapy.

Pulmonary rehabilitation and endothelial function in patients with chronic obstructive pulmonary disease: A prospective cohort study

BackgroundChronic obstructive pulmonary disease (COPD) is associated with subclinical atherosclerosis and endothelial dysfunction, thereby leading to increased cardiovascular risk. In the present study, we evaluated the changes in endothelium-dependent flow-mediated dilation (FMD) in a cohort of severe COPD patients undergoing pulmonary rehabilitation. MethodsConsecutive COPD patients referred to our Pulmonary Rehabilitation Unit were screened for inclusion. All study procedures were performed at hospital admission and discharge. ResultsOf 78 patients screened for eligibility, a total of 40 participants (67.5% males, median age 72.5 years) were included. After pulmonary rehabilitation, a significant improvement in functional parameters, exercise capacity, and measures of disability and quality of life were documented. FMD changed from 3.25% (IQR: 2.31–4.26) to 4.95% (IQR: 3.57–6.02), corresponding to a 52.3% increase of its median value (P < 0.001). Significantly lower changes in FMD were documented in COPD patients with hypercholesterolemia as compared to those without (+0.33% ± 1.61 vs. +1.62% ± 1.59, P = 0.037). Changes in FMD (ΔFMD) were positively associated with changes in forced expiratory volume in 1 s (FEV1), when expressed both as absolute values (ΔFEV1) (r = 0.503, P = 0.002) and as percentages of predicted values (ΔFEV1%) (r = 0.608; P < 0.001). In multiple linear regressions, after adjusting for major cardiovascular risk factors, ΔFEV1 (β=0.342; P = 0.049) and ΔFEV1% (β=0.480; P = 0.015) were both confirmed as independent predictors of ΔFMD. ConclusionsResults of our study suggest that endothelial function may improve in COPD after pulmonary rehabilitation. The potential beneficial effect in terms of cardiovascular risk prevention should be evaluated in ad hoc designed studies.

Transcatheter aortic valve implantation improves endothelial and autonomic function

Abstract Funding Acknowledgements Type of funding sources: None. Background Degenerative aortic stenosis is the leading native valve pathology in developed countries. Its degeneration process is affected by aging, common cardiovascular risk factors and an atherosclerotic-like process preceded by endothelial and autonomic dysfunction. With the increasing integration of transcatheter aortic valve implantation (TAVI) in the treatment of aortic stenosis in the elderly, research is being intensively oriented into its beneficial effect on the cardiovascular system. Measurements of vascular function with flow mediated dilatation (FMD) and autonomic cardiac function using heart rate variability parameters represent a validated method for treatment evaluation at different time-points. Purpose The purpose of our study was to assess whether haemodynamic and structural changes after TAVI will have a positive impact on endothelial and autonomic cardiac function on early and late follow-up. Methods 50 patients with severe aortic stenosis destinated to TAVI were prospectively included. Data was collected at baseline (24 hours before the procedure), on early follow-up (48 hours after the procedure) and on late follow-up (6 months after the procedure). While different heart rate variability parameters were obtained using a high-resolution electrocardiogram, FMD was assessed using a standardized ultrasound-based process with induced forearm hyperaemia. Results 43 patients completed the study (mean age 81 (75-85); 60% women). FMD measurements significantly changed from baseline to early follow-up (2.8 ± 1.5 % to 4.7 ± 2.7 %, p &amp;lt; 0.001). Improvement was persistent on late follow up (4.8 ± 2.7 %, p = 0.936). Moreover, heart rate variability parameters remained unchanged on early follow-up and improved 6 months after. Late follow-up statistical significance was reached by HF, a frequency-domain parameter (5231 ± 1783 to 6507 ± 1789 ms2; p = 0.029) and two Poincare diagram parameters: RR ecc (682 to 906 ms2; p &amp;lt; 0.001) and SDRR (9.6 to 23.9 ms; p = 0.001). Significant predictors of FMD change were as following: baseline maximal aortic valve velocity (R = 0.415; p = 0.011), mean aortic gradient (R = 0.373; p = 0.018), indexed stroke volume (R = 0.503; p = 0.006) and NT-proBNP (R = 0.491; p = 0.001). Conclusions Both endothelial and autonomic function improved after TAVI. While FMD seems to change early due to acute haemodynamic changes attributed to aortic valve stenosis resolution, autonomic cardiac functions remain stable and ameliorate late after procedure, likely reflecting left ventricular reverse remodelling.

Improved Endothelial and Autonomic Function after Transcatheter Aortic Valve Implantation

Background: Degenerative aortic stenosis is an atherosclerotic-like process associated with impaired endothelial and autonomic function. Transcatheter aortic valve implantation (TAVI) has become a treatment of choice for patient with severe degenerative aortic stenosis at high surgical risk. The effect of this procedure on endothelial function measured with flow mediated dilatation (FMD) and autonomic function measured with heart rate variability (HRV) at different time-points of disease management (early and late follow-up) remains unknown. Methods: We prospectively included 50 patients with severe aortic stenosis who were deemed suitable for TAVI by the Heart Team. FMD and HRV parameters were collected at baseline (&lt;24 h pre-TAVI), at early follow-up (up to 48 h post-TAVI) and at late follow-up (3–6 months post-TAVI). Results: 43 patients (mean age 81 (75–85); 60% women) completed the study. FMD significantly improved from 2.8 ± 1.5% before TAVI to 4.7 ± 2.7% early after TAVI (p &lt; 0.001) and was later maintained on late follow-up (4.8 ± 2.7%, p = 0.936). Conversely, high-resolution ECG parameters remained preserved at early and improved at late follow-up after TAVI. Significant improvement was detected in a high frequency-domain parameter—HF (from 5231 ± 1783 to 6507 ± 1789 ms2; p = 0.029) and in two Poincare plot parameters: ratio of the short- and long-term R-R variability in the Poincare plot—SD1/SD2 (from 0.682 to 0.884 ms2; p = 0.003) and short-term R-R variability in the Poincare plot—SDRR (from 9.6 to 23.9 ms; p = 0.001). Echocardiographic parameters comprising baseline maximal aortic valve velocity (R = 0.415; p = 0.011), mean aortic gradient (R = 0.373; p = 0.018), indexed stroke volume (R = 0.503; p = 0.006), change in aortic valve maximal velocity (R = 0.365; p = 0.031), change in mean aortic gradient (R = 0.394; p = 0.019) and NT-proBNP (R = 0.491; p = 0.001) were found as significant predictors of change in FMD. Conclusions: Endothelial function measured with FMD and autonomic function obtained with HRV parameters significantly improve after TAVI. While endothelial function improves early and is maintained later after TAVI, autonomic function remains stable and improves on late follow-up. This is most likely caused by early hemodynamic changes after resolution of aortic valve obstruction and gradual left ventricular remodeling. Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT04286893.

Oxidative stress-related impairment of endothelial function in uncomplicated obesity

Purpose: Visceral obesity is associated with vascular oxidative stress and development of hypertension. Therefore, we tested the hypothesis that suppression of vascular oxidative stress in adults with visceral obesity would improve endothelium-dependent dilation. Methods: IV infusion of a water-soluble antioxidant (ascorbic acid) was performed in 15 middle-age obese adults (3 men/12 women) without diabetes or hypertension in a placebo-controlled, double-blinded, crossover study design. Ascorbic acid was infused at 0.06g/kg fat free mass in 100 ml saline at 5 mL/min over 20 min (bolus) followed by a drip infusion at 0.02 g/kg fat-free mass in 30 ml saline at 0.5 mL/min over 60 min. Endothelium-dependent dilation was assessed via brachial artery flow-mediated dilation (FMD) and expressed as % increase in diameter from baseline before forearm occlusion. Results: Android fat distribution in the visceral cavity (VAT%) was 39 ± 10% and body mass index (BMI) was 37 ± 6 kg/m2. IV infusion significantly increased plasma ascorbic acid concentrations (Baseline: 42 ± 2 vs. Bolus: 66 ± 6 vs. End: 62 ± 4 μmol/L, P&lt;0.001). Compared with baseline, bolus infusion of ascorbic acid significantly increased FMD (Baseline: 5.8 ± 2.5 vs. Bolus: 9.0 ± 4.0 vs. End: 8.0 ± 4.2 %, P=0.01), which remained after statistically adjusting for the stimulus (shear rate area under the curve) via analysis of covariance (P=0.04). No significant change in FMD was observed following placebo (saline) during a separate study visit (Baseline: 8.0 ± 4.4 vs. Bolus: 8.3 ± 3.9 vs. End: 8.6 ± 2.9 %, P=0.86). Conclusions: These preliminary findings suggest that acute elevations in plasma ascorbic acid concentrations improve endothelium-dependent dilation in middle-aged adults with visceral obesity. Future studies should target mechanisms by which mediators of oxidative stress in obesity (e.g., hyperlipidemia, hyperinsulinemia) inhibit nitric oxide-mediated vasodilation. Funding and support: R01HL159370-01 (S.W.H.). This work was also supported by a CTSA grant from NCATS awarded to the University of Kansas for Frontiers: University of Kansas Clinical and Translational Science Institute (# UL1TR002366). The contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH or CTSA. This is the full abstract presented at the American Physiology Summit 2023 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.

The associations of markers of endothelial dysfunction with hip fracture risk.

Endothelial dysfunction underlies the development of atherosclerotic vascular disease. Vascular disease, in turn, is associated with the risk of osteoporotic fractures, such as hip fractures. Here, we examine whether two measures of endothelial dysfunction are related to hip fracture risk. Participants for this study were 2792 individuals (mean age 78.6years) who had flow-mediated dilation (FMD) measured after ischemia in the forearm and 2255 adults (mean age 73.3years) with measured soluble intercellular adhesion molecule (siCAM) levels, a constitutive endothelial cell membrane protein associated with the initiation of atherosclerosis. Mean follow-up was 9.7 and 11.7years, respectively. There were 375 and 265 incident hip fractures, respectively, in each group. In Cox proportional hazards models, there was no significant association between FMD response and incident hip fracture (HR per 1% higher FMD was 0.98 [0.93, 1.04]; p = 0.44). In exploratory analyses, when data were examined dichotomously, participants in the lowest 80% of FMD (≤ 4.5%) had an adjusted 1.29 (0.98, 1.68; p = 0.067) higher hazard of hip fracture compared to participants in the upper 20% of FMD change. There were no significant associations between siCAM and incident hip fracture whether examined as a continuous or dichotomized variable. Among older adults, two measures of endothelial dysfunction were not significantly associated with hip fracture risk. There was a trend for higher fracture risk with lower FMD.