Peripheral Artery Endothelial Function Research Articles

Effects of pre-exercise intake of plant- and animal-based foods on arterial function and aerobic exercise capacity in healthy young men: a randomized cross-over trial.

The purpose of this study was to examine the effects of plant- versus animal-based food intake before exercise on arterial function and subsequent aerobic exercise capacity. Eleven healthy adult males (mean age, 22.6±1.8 years) participated in this study. A plant- or animal-based randomized meal type crossover comparison was conducted on separate days with a uniform protein, fat, and carbohydrate balance. Both carotid-femoral pulse wave velocity (cfPWV), femoral-ankle pulse wave velocity (faPWV), and brachial artery flow-mediated dilatation (FMD) were measured as indexes of aortic and peripheral arterial stiffness and vascular endothelial function, respectively, before and at 120min after the meal. After these measurements, maximal oxygen uptake was assessed using a graded power test on an electronically braked cycle ergometer. The results revealed that cfPWV was significantly lower, whereas FMD was significantly higher, at 120min after compared with before the plant-based meal (p=0.01 and 0.02, respectively). By contrast, cfPWV and FMD did not change at 120min after compared with before the animal-based meal. In addition, faPWV did not change at 120min after compared with before the meal for either meal type. Maximal oxygen uptake was higher in the plant- than in the animal-based meal type (p=0.02). These results suggest that pre-exercise plant-based food intake may improve central arterial stiffness and vascular endothelial function, which may have favorable implications for aerobic exercise capacity.

Olive pomace oil can improve blood lipid profile: a randomized, blind, crossover, controlled clinical trial in healthy and at-risk volunteers

PurposeThis study aimed to assess the effect of dietary consumption of olive pomace oil (OPO) on blood lipids (primary outcome) and other cardiovascular disease (CVD) risk factors (blood pressure, inflammation and endothelial function as secondary outcomes).MethodsA randomized, controlled, blind, crossover intervention was carried out in healthy and at-risk (hypercholesterolemic) subjects. Participants consumed daily 45 g of OPO or high-oleic acid sunflower oil (HOSO) as control oil during 4 weeks.ResultsOPO significantly reduced low-density lipoprotein cholesterol (LDL-C; P = 0.003) and apolipoprotein B (Apo B; P = 0.022) serum concentrations, and LDL/HDL ratio (P = 0.027) in healthy and at-risk volunteers. These effects were not observed with HOSO. Blood pressure, peripheral artery tonometry (PAT), endothelial function and inflammation biomarkers were not affected.ConclusionsRegular consumption of OPO in the diet could have hypolipidemic actions in subjects at cardiovascular risk as well as in healthy consumers, contributing to CVD prevention.Clinical trial registryNCT04997122, August 8, 2021, retrospectively registered.

Characterization of Cardiac, Vascular, and Metabolic Changes in Young Childhood Cancer Survivors.

Background: Childhood cancer survivors (CCS) are at an increased risk for cardiovascular diseases (CVD). It was the primary aim of this study to determine different measures of cardiac, carotid, lipid, and apolipoprotein status in young adult CCS and in healthy controls.Methods: Cardiac and common carotid artery (CCA) structure and function were measured by ultrasonography. Lipids and apolipoproteins were measured in the blood. Peripheral arterial endothelial vasomotor function was assessed by measuring digital reactive hyperemia index (PAT-RHI) using the Endo-PAT 2000.Results: Fifty-three CCS (20–30 years, 35 men) and 53 sex-matched controls were studied. The CCS cohort was divided by the median dose of anthracyclines into a low anthracycline dose (LAD) group (50–197 mg/m2, n = 26) and a high anthracycline dose (HAD) group (200–486 mg/m2, n = 27). Carotid distensibility index (DI) and endothelial function determined by PAT-RHI were both lower in the CCS groups compared with controls (p < 0.05 and p = 0.02). There was no difference in carotid intima media thickness. Atherogenic apolipoprotein-B (Apo-B) and the ratio between Apo-B and Apoliprotein-A1 (Apo-A1) were higher in the HAD group compared with controls (p < 0.01). Apo-B/Apo-A1-ratio was over reference limit in 29.6% of the HAD group, in 15.4% of LAD group, and in 7.5% of controls (p = 0.03). Measured lipid markers (low density lipoprotein and total cholesterol and triglycerides) were higher in both CCS groups compared with controls (p < 0.05). Systolic and diastolic function were measurably decreased in the HAD group, as evidenced by lower EF (p < 0.001) and lower é-wave (p < 0.005) compared with controls. CCA DI correlated with Apo-B/Apo-A1-ratio and Apo-A1. Follow-up time after treatment correlated with decreased left ventricular ejection fraction (p = 0.001).Conclusion: Young asymptomatic CCS exhibit cardiac, vascular, lipid, and apolipoprotein changes that could account for increased risk for CVD later in life. These findings emphasize the importance of cardiometabolic monitoring even in young CCS.

Effects of Land versus Water Walking Interventions on Vascular Function in Older Adults.

Endothelial dysfunction is an early and integral atherogenic event. Interventions that improve endothelial function also reduce cardiovascular risk. Due largely to the direct hemodynamic effects of repetitive exercise on the artery wall, exercise training has shown to enhance endothelial function. Land walking (LW) and water walking (WW) induce distinct hemodynamic responses, so the comparison of their effects provides an approach to study shear stress effects on endothelial function. We hypothesized that LW and WW training would have different effects on peripheral artery endothelial function. Fifty-one sedentary, older (age = 61.9 ± 6.6 yr, 23.5% male) individuals were randomized into one of three groups: control (n = 16), or one of two exercise groups consisting of 3 × 50 min supervised and individually tailored walking sessions per week for 24 consecutive weeks, performed either on LW (n = 17) or on WW (n = 18). Brachial artery endothelial function (flow-mediated dilation) and smooth muscle cell function (glyceryl trinitrate administration) were tested in all participants before (week 0) and after (week 24) the intervention. Differences were apparent in flow-mediated dilation change between the LW group (week 0, 5.39% ± 0.71%, to week 24, 7.77% ± 0.78%; P = 0.009) and the control group (week 0, 5.87% ± 0.73%, to week 24, 5.78% ± 0.78%). No differences in artery dilation response were found after glyceryl trinitrate administration (all P > 0.05). This study suggests that 6-month center-based LW may be superior to WW in terms of improvement in arterial endothelial function in older sedentary individuals.

Effect of different walking break strategies on superficial femoral artery endothelial function.

Breaking up prolonged sitting with physical activity (PA) breaks prevents conduit artery dysfunction. However, the optimal break strategy to achieve this, in terms of the frequency or duration of PA, is not known. This study assessed the effect of breaking up sitting with different PA break strategies on lower limb peripheral artery endothelial function. Fifteen participants (10 male, 35.8 ± 10.2 years, BMI: 25.5 ± 3.2 kg m−2) completed, on separate days, three 4‐h conditions in a randomized order: (1) uninterrupted sitting (SIT), (2) sitting with 2‐min light‐intensity walking breaks every 30 min (2WALK), or (3) sitting with 8‐min light‐intensity walking breaks every 2 h (8WALK). At baseline and 4 h, superficial femoral artery function (flow‐mediated dilation; FMD), blood flow, and shear rate (SR) were assessed using Doppler ultrasound. For each condition, the change in outcome variables was calculated and data were statistically analyzed using a linear mixed model. There was no significant main effect for the change in FMD (P = 0.564). A significant main effect was observed for the change in blood flow (P = 0.022), with post hoc analysis revealing a greater reduction during SIT (−42.7 ± 14.2 mL·min) compared to 8WALK (0.45 ± 17.7 mL·min; P = 0.012). There were no significant main effects for mean, antegrade, or retrograde SR (P > 0.05). Superficial femoral artery blood flow, but not FMD, was reduced following uninterrupted sitting. This decline in blood flow was prevented with longer duration, less frequent walking breaks rather than shorter, more frequent breaks suggesting the dose (duration and frequency) of PA may influence the prevention of sitting‐induced decreases in blood flow.

Peripheral artery endothelial function responses to altered shear stress patterns in humans.

What is the central question of this study? What is the effect of altered shear stress pattern, with or without concurrent neurohumoral and metabolic activation, on the acute endothelial function response assessed via brachial artery flow-mediated dilatation? What is the main finding and its importance? Despite generating distinctive shear stress patterns (i.e. increases in anterograde only, anterograde only with neurohumoral and metabolic activation, and both anterograde and retrograde), similar acute improvements were observed in the brachial artery flow-mediated dilatation response in all conditions, indicating that anterograde and/or turbulent shear stress might be the essential element to induce acute increases in endothelial function. Endothelial function is influenced by both the direction and the magnitude of shear stress. Acute improvements in endothelial function have mostly been attributed to increased anterograde shear, whereas results from many interventional models in humans suggest that enhancing shear stress in an oscillatory manner (anterograde and retrograde) might be optimal. Here, we determined the acute brachial artery shear stress (SS) and flow-mediated dilatation (FMD) responses to three shear-altering interventions [passive heat stress (HEAT), mechanical forearm compression (CUFF) and handgrip exercise (HGEX)] and examined the relationship between changes in oscillatory shear index (OSI) and changes in FMD. During separate visits, 10 young healthy men (22±3years old) underwent 10min of HEAT, CUFF or HGEX in their left forearm. Anterograde and retrograde SS, Reynolds number, OSI and FMD were assessed at rest and during/after each intervention. Anterograde SS increased during all interventions in a stepwise manner (P<0.05 between interventions), with the change in HGEX (∆37.7±12.2dyncm-2 , P<0.05)>CUFF (∆25.1±11.9dyncm-2 , P<0.05)>HEAT (∆14.5±7.9dyncm-2 , P<0.05). Retrograde SS increased during CUFF (∆-19.6±4.3dyncm-2 , P<0.05). Anterograde blood flow was turbulent (i.e. Reynolds number≥|2000|) during all interventions (P<0.05). The relative FMD improved after all interventions (P=0.01), and there was no relationship between ∆OSI and ∆FMD. We elicited changes in SS profiles including increased anterograde SS (HEAT and HGEX) and both increased anterograde and retrograde SS (CUFF); regardless of the SS pattern, FMD improved to the same extent. These findings suggest that the presence of anterograde and/or turbulent SS might be the key to optimizing endothelial function in acute assessment protocols.

Fast-food meal reduces peripheral artery endothelial function but not cerebral vascular hypercapnic reactivity in healthy young men.

Consumption of a representative fast‐food meal (FFMeal) acutely impairs peripheral conduit artery vascular function; however, the effect on cerebral vascular function remains unknown. This study tested the hypothesis that a FFMeal would impair cerebral vascular function as indexed by an attenuated increase in cerebral vascular conductance (CVCI) in the middle cerebral artery (MCA) during a hypercapnic challenge. Ten healthy men (age: 24 ± 3 years, BMI: 24.3 ± 3.8 kg/m2) were studied under two conditions; a standardized FFMeal (990 kcals, 50% fat, 36% carbohydrate, 14% protein, and 2120 mg sodium) and a fasting control condition. Basal hemodynamics, cerebral vasomotor reactivity (CVMR), and brachial artery flow‐mediated dilation (BA FMD) were completed after an overnight fast (Pre) and again 2 h and 4 h later both days. To assess CVMR, subjects rebreathed from a 5‐L bag while MCA velocity (MCAV mean) was measured using transcranial Doppler (TCD) ultrasound and converted into CVCI (MCAV mean/mean arterial pressure). Peripheral artery endothelial function was assessed via BA FMD following a standard 5‐min occlusion protocol. As expected, BA FMD was reduced at 2 h (Pre: 6.6 ± 1.7% vs. 5.2 ± 1.8%, P = 0.01). However, despite significant impairment in BA FMD, neither peak CVCI %baseline nor CVMR was affected by the FFMeal (Control–Pre: 1.9 ± 1.1, 2 h: 2.1 ± 1.1, 4 h: 1.7 ± 1.1 ∆CVCI%·∆PETCO 2 −1 vs. FFMeal–Pre: 2.1 ± 1.1, 2 h: 2.2 ± 0.7, 4 h: 1.9 ± 0.9 ∆CVCI%·∆PETCO 2 −1, time × condition P = 0.88). These results suggest that cerebral vascular reactivity to hypercapnia in healthy young men is not altered by an acute FFMeal.

Performing under pressure: hypertension and the regulation of cerebral oxygen delivery.

Performing under pressure: hypertension and the regulation of cerebral oxygen delivery.

Changes in brachial artery endothelial function and resting diameter with moderate-intensity continuous but not sprint interval training in sedentary men.

Moderate-intensity continuous training (MICT) improves peripheral artery function in healthy adults, a phenomenon that reverses as continued training induces structural remodeling. Sprint interval training (SIT) elicits physiological adaptations similar to MICT, despite a lower exercise volume and time commitment; however, its effect on peripheral artery function and structure is largely unexplored. We compared peripheral artery responses to 12 wk of MICT and SIT in sedentary, healthy men (age = 27 ± 8 yr). Participants performed MICT (45 min of cycling at 70% peak heart rate; n = 10) or SIT (3 × 20-s "all out" cycling sprints with 2 min of recovery; n = 9), and responses were compared with a nontraining control group (CTL, n = 6). Allometrically scaled brachial flow-mediated dilation (FMD) increased 2.2% after 6 wk of MICT and returned to baseline levels by 12 wk, but did not change in SIT or CTL (group × time interaction, P = 0.04). Brachial artery diameter increased after 6 and 12 wk (main effect, P = 0.03), with the largest increases observed in MICT. Neither training protocol affected popliteal relative FMD and diameter, or central and lower limb arterial stiffness (carotid distensibility, central and leg pulse wave velocity) (P > 0.05 for all). Whereas earlier and more frequent measurements are needed to establish the potential presence and time course of arterial responses to low-volume SIT, our findings suggest that MICT was superior to the intense, but brief and intermittent SIT stimulus at inducing brachial artery responses in healthy men.NEW & NOTEWORTHY We compared the effects of 12 wk of moderate-intensity continuous training (MICT) and sprint interval training (SIT) on peripheral artery endothelial function and diameter, and central and lower limb stiffness in sedentary, healthy men. Whereas neither training program affected the popliteal artery or stiffness indexes, we observed changes in brachial artery function and diameter with MICT but not SIT. Brachial artery responses to SIT may follow a different time course or may not occur at all.

Distribution of peripheral arterial stiffness and endothelial function as well as their correlations with cardiovascular risk factors in children and adolescents

To investigate the distribution of peripheral arterial stiffness, endothelial function and their correlations with cardiovascular risk factors in the 7-17 year-olds. Normal weight and obese subjects aged 7-17 years with completed data on questionnaires, anthropometric and blood biochemical tests, were recruited from a cross-sectional population-based study on childhood hypertension in Minhang district of Shanghai. Automatic waveform analyzer (BP-203RPE-I) and Endopat 2000 were used to measure the arterial stiffness. Endothelial function with brachial-ankle pulse wave velocity (baPWV) and reactive hyperemia index (RHI) were recorded. BaPWV and RHI were standardized by age. Skewed biochemical variables were log transformed. Linear correlation analysis was performed to observe association between baPWV, RHI and other measured variables. A total of 452 normal-weight and 94 obese subjects were recruited, including 299 males. Data showed that baPWV and RHI increased with age in normal weight subjects(r=0.33, P<0.01; r=0.36, P<0.01). RESULTS from Linear correlation analysis revealed that baPWV was positively correlated with BMI (r=0.13, P=0.002), systolic blood pressure (SBP) (r=0.20, P<0.01), diastolic blood pressure (DBP) (r=0.27, P<0.01), triglycerides (TG) (r=0.11, P=0.010), insulin (r=0.21, P=0.004) and the HOMA insulin resistance index (r=0.21, P=0.005), but negatively correlated with high-density lipoprotein cholesterol (r=-0.09, P=0.039). RHI was positively correlated with BMI (r=0.10, P=0.018) but negatively correlated with DBP (r=-0.10, P=0.016). Males had higher baPWVs than females (P=0.04). However, RHI did not differ between genders. The fact that baPWV and RHI increased along with age, indicated that the arterial stiffness and endothelial function continued to develop in normal weight childhood and adolescence. Arterial stiffness was correlated with cardiovascular risk-related parameters whereas endothelial function was not. BaPWV might be more sensitive in evaluating the cardiovascular risk in children and adolescents than RHI did.

The Effect of Breaking up Prolonged Sitting on Cerebral Blood Flow

Prolonged sitting has a detrimental effect on peripheral conduit artery endothelial function, whilst breaking up prolonged sitting time can prevent such impairments. The effect of prolonged sitting and breaking up sitting time on cerebral blood flow (CBF) is currently unknown. Importantly, decreased CBF is related to lower cognitive functioning and increased risk of cognitive impairment and dementia. PURPOSE:To determine the effect of uninterrupted sitting and breaking up sitting time with light intensity walking on CBF in healthy subjects. METHODS: Thirteen healthy participants (8 male, 37.3±10.1 years old, BMI: 25.6±3.4 kg/m2) completed, on separate days, three 4 hr conditions in a counterbalanced order: a) uninterrupted sitting, b) sitting with 2-min light intensity walking breaks every 30 mins, or c) sitting with 8-min light intensity walking breaks every 2 hrs. Middle cerebral artery blood flow velocity (MCAv) was measured using transcranial Doppler in a supine position at BASELINE, 2HRS and 4HRS. Beat-to-beat blood pressure was assessed (Finometer), enabling the calculation of cerebrovascular conductance (CVC). Between each measurement participants remained seated and were permitted to complete desk-based tasks. RESULTS:There was no change over time in MCAv (BASELINE: 57.3±2.4 cm/s, 2HRS: 56.5±2.3 cm/s, 4HRS: 56.3±2.1 cm/s; p=0.77) or CVC (BASELINE: 0.71±0.04 cm/s/mmHg, 2HRS: 0.70±0.04 cm/s/mmHg, 4HRS: 0.67±0.03 cm/s/mmHg; p=0.18), or between the conditions (MCAv: p=0.18; CVC: p=0.11). Moreover, there was no interaction between condition and time for MCAv (p=0.56) or CVC (p=0.64). CONCLUSIONS:Contrary to previous findings which indicate that prolonged sitting can reduce peripheral endothelial function, our data suggest that neither CBF velocity nor CVC are altered following prolonged sitting for 4 hrs. Additionally, breaking up this sitting time with walking breaks did not further affect CBF velocity or CVC. Whilst our data indicate unaltered CBF following uninterrupted sitting, changes in cerebrovascular function may occur independent of changes in blood flow. Further research is therefore needed to determine whether measures of cerebrovascular function, including autoregulation and reactivity, are influenced by prolonged sitting. Supported by BBSRC Grant BB/L017237/1

Comprehensive assessment of impaired peripheral and coronary artery endothelial functions in smokers using brachial artery ultrasound and oxygen-15-labeled water PET

BackgroundComprehensive evaluation of endothelium-dependent and endothelium-independent vascular functions in peripheral arteries and coronary arteries in smokers has never been performed previously. Through the use of brachial artery ultrasound and oxygen-15-labeled water positron emission tomography (PET), we sought to investigate peripheral and coronary vascular dysfunctions in smokers. Methods and resultsEight smokers and 10 healthy individuals underwent brachial artery ultrasound at rest, during reactive hyperemia [250mmHg cuff occlusion (flow-mediated dilatation (FMD)], and following sublingual nitroglycerin (NTG) administration. Myocardial blood flow (MBF) was assessed through O-15-labeled water PET at rest, during adenosine triphosphate (ATP) administration, and during a cold pressor test (CPT). Through ultrasound, smokers were shown to have significantly reduced %FMD compared to controls (6.62±2.28% vs. 11.29±2.75%, p=0.0014). As assessed by O-15-labeled water PET, smokers were shown to have a significantly lower CPT response than were controls (21.1±9.5% vs. 50.9±16.9%, p=0.0004). There was no relationship between %FMD and CPT response (r=0.40, p=0.097). Endothelium-independent vascular dilatation was similar for both groups in terms of coronary flow reserve with PET (p=0.19). Smokers tended to have lower %NTG in the brachial artery (p=0.055). ConclusionsSmokers exhibited impaired coronary endothelial function as well as peripheral brachial artery endothelial function. In addition, there was no correlation between PET and ultrasound measurements, possibly implying that while smokers may have systemic vascular endothelial dysfunction, the characteristics of that dysfunction may be different in peripheral arteries and coronary arteries.

Effect of aspirin on acute changes in peripheral arterial stiffness and endothelial function following exertional heat stress in firefighters: The factorial group results of the Enhanced Firefighter Rehab Trial.

Peripheral arterial stiffness and endothelial function, which are independent predictors of cardiac events, are abnormal in firefighters. We examined the effects of aspirin on peripheral arterial stiffness and endothelial function in firefighters. Fifty-two firefighters were randomized to receive daily 81 mg aspirin or placebo for 14 days before treadmill exercise in thermal protection clothing, and a single dose of 325 mg aspirin or placebo immediately following exertion. Peripheral arterial augmentation index adjusted for a heart rate of 75 (AI75) and reactive hyperemia index (RHI) were determined immediately before, and 30, 60, and 90 minutes after exertion. Low-dose aspirin was associated with lower AI75 (-15.25±9.25 vs -8.08±10.70, p=0.014) but not RHI. On repeated measures analysis, treatment with low-dose aspirin before, but not single-dose aspirin after exertion, was associated with lower AI75 following exertional heat stress (p=0.018). Low-dose aspirin improved peripheral arterial stiffness and wave reflection but not endothelial function in firefighters.

Cancer therapy-induced autonomic dysfunction in early breast cancer: Implications for aerobic exercise training

Breast cancer is the most common malignancy affecting women and the second leading cause of cancer death in women in the United States [1]. Due to improvements in detection and adjuvant therapy, breast cancer specific mortality has decreased significantly in women with early stage disease, and the five-year relative survival rate for early stage disease has increased from 80% in 1950 to 89% today [1]. Increased breast cancer specific survival, however, is at risk of being offset by the potential late occurring cardiovascular toxic effects of oncologic therapy. Indeed, among women with early breast cancer, particularly those over age 65, cardiovascular disease (CVD) is now the predominant cause of mortality, and these women are also at increased risk of CVD compared with age-matched women without a history of breast cancer [2].

Left ventricular structure and geometry, peripheral artery endotheliumdependent vasodilatation, antihypertensive effect of ACE inhibitors, and hormone replacement therapy in premenopausal women with arterial hypertension

Aim.To summarize the data on the 7-month treatment with ACE inhibitors (lisinopril) and hormone replacement therapy, HRT (femoston) – in particular, the effects on left ventricular (LV) structure and geometry, peripheral artery endothelium-dependent vasodilatation (EDVD), blood pressure (BP), and clinical perimenopausal symptoms – in premenopausal women with arterial hypertension (AH).Material and methods.The study included 84 premenopausal women with Stage II AH and LV myocardial hypertrophy (LVH). Group I (47 women; mean age 48,6 years). The clinical symptoms included nighttime hyperhidrosis and hot flashes. In Group II (37 women, mean age 53,2 years). The clinical symptoms in Group II participants included hyperhidrosis, hot flashes, malaise, and dysphoria. Group II received lisinopril (1– mg/day) and femoston (2/10/2 mg); Group I was administered lisinopril in the same dose and placebo. Clinical examination, the measurement of BP and heart rate (HR), ECG, EDVD assessment, and echocardiography (EchoCG) were performed at baseline, during the treatment, and 7 months after the end of the treatment.Results.Lisinopril therapy demonstrated a good antihypertensive effect in premenopausal women with AH, while also preventing the progression of LVH and dilatation of left heart chambers.Conclusion.The studied medications improved peripheral artery endothelial function and were well tolerated. Femoston was highly compatible with cardiac therapy and effectively reduced clinical symptoms in premenopausal women with AH.

Early effects of gastric bypass on endothelial function, inflammation, and cardiovascular risk in obese patients

Obesity is associated with a chronic low-grade inflammatory state, insulin resistance, and endothelial dysfunction, all of which contribute to increased risk of cardiovascular disease. We hypothesized that gastric bypass would produce rapid improvements in endothelial function, reduce inflammation, and lead to a decrease in cardiovascular risk. We performed a prospective study of morbidly obese patients who underwent laparoscopic Roux-en-Y gastric bypass (RYGB). Clinical data, biochemical markers of inflammation, and parameters indicative of cardiovascular risk were collected preoperatively and at 3 and 6 months postoperatively. Metabolic and inflammatory mediators that were quantified included C-reactive protein, fibrinogen, PAI-1, IL-6, IL-10, IL-1Ra, adiponectin, leptin, triglycerides, total cholesterol, HDL, LDL, glucose, insulin, and HbA1c. Brachial artery reactivity testing (BART) was performed to assess peripheral arterial endothelial function, and Framingham cardiovascular risk score (FRS) was calculated on all study participants pre- and postoperatively. Fifteen patients (11 female) were enrolled (age = 49.2 ± 10.4 years; BMI = 48.1 ± 5.3 kg/m(2)). Six months post RYGB, mean BMI decreased to 35.4 ± 4.5, corresponding to 51.7% excess weight loss (P < 0.001). Mean waist circumference decreased significantly from 132 cm at baseline to 110 cm at 3 months (P = 0.003) and 107 cm at 6 months (P < 0.001). Six months after RYGB, weight loss led to significant improvements in clinical parameters indicative of cardiovascular disease or risk, including brachial artery diameter, endothelial independent vasodilation, and FRS. Favorable improvements in the proinflammatory markers CRP (P = 0.01) and leptin (P = 0.005), the anti-inflammatory mediator adiponectin (P = 0.002), and insulin sensitivity (HOMA-IR, P = 0.007) were evident at 3 months. At 6 months, improvements in CRP, leptin, and fasting insulin were maintained and fibrinogen levels also decreased (P = 0.047). Adiponectin continued to increase at 6 months (P = 0.004). Gastric bypass is associated with early reversal of endothelial dysfunction, a more favorable inflammatory milieu, and, most importantly, a reduction in cardiovascular risk.

The Effect of Revascularization of Atherosclerotic Renal Artery Stenosis on Coronary Flow Reserve and Peripheral Endothelial Function

Background: Patients with atherosclerotic renovascular disease (ARVD) are at increased risk of heart disease because of associated hypertension, coronary artery disease, cardiac failure and chronic kidney disease. Although suggested to be beneficial, the cardiac effects of renal artery revascularization have not been well characterized. Our aim was to analyze the effects of percutaneous dilatation of renal artery stenosis (RAS) in ARVD patients on coronary and peripheral vascular function. Methods: Nineteen ARVD patients [11 females and 8 males, age at study entry (mean ± SD) 69 ± 10 years] were treated by dilatation of unilateral (n = 9) or bilateral (n = 10) RAS, mainly because of uncontrolled or refractory hypertension. The patients were studied before and after the procedure (103 ± 29 days). They underwent echocardiography and peripheral artery endothelial function testing using flow-mediated dilatation (FMD) of brachial artery at rest and during reactive hyperemia. Myocardial blood flow was measured using quantitative PET perfusion imaging at baseline and during dipyridamole-induced hyperemia. Results: Peripheral endothelial function, tested by FMD, as well as systolic blood pressure and left ventricular mass were improved in patients with bilateral RAS. However, myocardial perfusion and coronary flow reserve (CFR) did not change after the RAS dilatation. Conclusion: This is the first study to analyze the stage of myocardial perfusion and CFR in ARVD patients. Although peripheral endothelial function, systolic blood pressure and left ventricular hypertrophy were improved in patients with bilateral RAS by revascularization of RAS, it did not have any effect on coronary perfusion.

Increased basal myocardial perfusion in patients with chronic kidney disease without symptomatic coronary artery disease

Even minor renal dysfunction is a powerful cardiovascular risk factor. The abnormalities in coronary and peripheral artery function in different stages of chronic kidney disease (CKD) remain poorly understood. Our aim was to test by a positron emission tomography (PET)-based method whether microvascular dysfunction, an early marker of coronary dysfunction, exists already in early stages of CKD. Myocardial blood flow was measured at baseline and during dipyridamole-induced hyperaemia by PET. Peripheral artery endothelial function was examined by measuring flow-mediated dilatation (FMD) of the brachial artery at rest and during reactive hyperaemia. Twenty-two patients with moderate to severe kidney failure and 10 healthy controls were investigated. Diabetic patients were excluded. Baseline characteristics were similar between the groups with the exception of antihypertensive medication in all CKD patients. The basal myocardial perfusion was statistically significantly higher in CKD patients than observed values in similarly aged controls. There was a statistically significant negative correlation between the baseline myocardial perfusion and the estimated glomerular filtration rate. Coronary flow reserve was comparable to healthy controls in all patients. FMD was significantly reduced in all patients with CKD regardless of the stage of kidney failure. Coronary flow reserve was normal although baseline myocardial blood flow was increased in all CKD patients as compared to healthy controls. Peripheral endothelial dysfunction was detected in all patients. Our findings suggest that coronary perfusion and peripheral vascular function are disturbed by different mechanisms in patients with CKD.

Sprint interval and traditional endurance training induce similar improvements in peripheral arterial stiffness and flow-mediated dilation in healthy humans

Low-volume sprint interval training (SIT), or repeated sessions of brief, intense intermittent exercise, elicits metabolic adaptations that resemble traditional high-volume endurance training (ET). The effects of these different forms of exercise training on vascular structure and function remain largely unexplored. To test the hypothesis that SIT and ET would similarly improve peripheral artery distensibility and endothelial function and central artery distensibility, we recruited 20 healthy untrained subjects (age: 23.3 +/- 2.8 yr) and had them perform 6 wk of SIT or ET (n = 5 men and 5 women per group). The SIT group completed four to six 30-s "all-out" Wingate tests separated by 4.5 min of recovery 3 days/wk. The ET group completed 40-60 min of cycling at 65% of their peak oxygen uptake (Vo2peak) 5 days/wk. Popliteal endothelial function, both relative and normalized to shear stimulus, was improved after training in both groups (main effect for time, P < 0.05). Carotid artery distensibility was not statistically altered by training (P = 0.29) in either group; however, popliteal artery distensibility was improved in both groups to the same degree (main effect, P < 0.05). We conclude that SIT is a time-efficient strategy to elicit improvements in peripheral vascular structure and function that are comparable to ET. However, alterations in central artery distensibility may require a longer training stimuli and/or greater initial vascular stiffness than observed in this group of healthy subjects.

Peripheral wave reflection and endothelial function in untreated essential hypertensive patients with and without the metabolic syndrome

Metabolic syndrome is associated with a high risk of cardiovascular disease in hypertension. We evaluated whether metabolic syndrome is associated with early vascular alterations, such as increased peripheral wave reflections and endothelial dysfunction, in untreated essential hypertensive patients. Augmentation index and pulse wave velocity were determined with applanation tonometry in 391 untreated hypertensive patients and 166 controls. Endothelium-dependent response was assessed as flow-mediated dilation of the brachial artery. Metabolic syndrome was defined according to the latest National Cholesterol Education Program Adult Treatment panel III. Hypertensive patients showed significantly (P < 0.001) increased augmentation index and central pulse wave velocity, as well as reduced flow-mediated dilation, compared with controls. No further impairment in augmentation index or flow-mediated dilation was observed between patients with or without the metabolic syndrome components and with increasing number of metabolic syndrome. Age and systolic blood pressure, but no other single factor of the metabolic syndrome, resulted as significant predictors of augmentation index and flow-mediated dilation. Female gender was associated with increased augmentation index (P < 0.05) in the presence of the metabolic syndrome. Central pulse wave velocity was selectively impaired by metabolic syndrome in both genders. Finally, reactive hyperemia was reduced in patients with the metabolic syndrome and decreased significantly with the increasing number of metabolic syndrome. In untreated hypertensive patients, the presence of metabolic syndrome, which selectively impairs central pulse wave velocity, does not account for a further deterioration of peripheral wave reflection and conduit artery endothelial function. Our results suggest that blood pressure, age and gender are important determinants of peripheral vascular structural and functional parameters in these subjects, irrespective of the metabolic syndrome.