The relative importance of vascular structure and function in predicting cardiovascular events

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.

Methods to evaluate vascular function: a crucial approach towards predictive, preventive, and personalised medicine

Endothelium, the gatekeeper of our blood vessels, is highly heterogeneous and a crucial physical barrier with the ability to produce vasoactive and protective mediators under physiological conditions. It regulates vascular tone, haemostasis, vascular inflammation, remodelling, and angiogenesis. Several cardio-, reno-, and cerebrovascular diseases begin with the dysfunction of endothelial cells, and more recently, COVID-19 was also associated with endothelial disease highlighting the need to monitor its function towards prevention and reduction of vascular dysfunction. Endothelial cells are an important therapeutic target in predictive, preventive, and personalised (3P) medicine with upmost importance in vascular diseases. The development of novel non-invasive techniques to access endothelial dysfunction for use in combination with existing clinical imaging modalities provides a feasible opportunity to reduce the burden of vascular disease.

This review summarises recent advances in the principles of endothelial function measurements. This article presents an overview of invasive and non-invasive techniques to determine vascular function and their major advantages and disadvantages. In addition, the article describes mechanisms underlying the regulation of vascular function and dysfunction and potential new biomarkers of endothelial damage. Recognising these biomarkers is fundamental towards a shift from reactive to 3P medicine in the vascular field. Identifying vascular dysfunction earlier with non-invasive or minimally invasive techniques adds value to predictive diagnostics and targeted prevention (primary, secondary, tertiary care). In addition, vascular dysfunction is a potential target for treatments tailored to the person.

Correlation between masked hypertension and endothelial dysfunction measured by flow-mediated dilation: a protocol of systematic review and meta-analysis

INTRODUCTION

A surrogate marker to evaluate artery endothelial response when stimulated by reactive hyperaemia, known as brachial flow-mediated dilation (FMD), has prognostic value in predicting hypertensive organ damage and cardiovascular disease events. However, the degree of correlation between brachial FMD and masked hypertension (MH) outcomes is still unclear. Therefore, the purpose of this study is to pool data regarding FMD with respect to MH.

METHODS AND ANALYSIS

Electronic databases MEDLINE, EMBASE, China National Knowledge Infrastructure and Cochrane Library will be searched for the following keywords: endothelial dysfunction, flow-mediated dilation, and masked hypertension, masked uncontrolled hypertension (MUCH) and prehypertension. The following are the eligibility criteria: population-adults (18 years old or older) without hypertension at baseline, with suspected endothelial dysfunction, or from MH/MUCH populations (office blood pressure <140/90 mm Hg and home blood pressure ≥135 mm Hg and/or 85 mm Hg) and from controlled clinical trials, cohort studies, or randomised and controlled trials; exposures-any metrics for FMD; comparisons-participants without MH or MUCH; and outcome-change in FMD between the case group and the control group. Two authors will be engaged in screening and collecting data independently; disagreements will be resolved through discussion. Data extraction will include primary data designated as HR, OR, correlations and regression coefficients. Comprehensive Meta-Analysis V.2.0 will be used to conduct related subgroup and sensitivity analyses and publication bias.

ETHICS AND DISSEMINATION

This study does not require ethics approval. It will be submitted to a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42020208362.

Comparison of cardiovascular outcomes and cardiometabolic risk factors between patients with type 2 diabetes treated with sodium-glucose cotransporter-2 inhibitors and dipeptidyl peptidase-4 inhibitors: a meta-analysis

AIMS 

Prevention of cardiovascular outcomes is a goal of the management of patients with type 2 diabetes mellitus patients as important as lowering blood glucose levels. Among the various glucose-lowering agents, the effects of sodium-glucose cotransporter-2 inhibitors (SGLT-2Is) and dipeptidyl peptidase-4 inhibitors (DPP-4Is) on cardiovascular outcomes have become the focus of recent researches.

METHODS AND RESULTS 

A systematic search was performed through several online database. All studies that compared the effects of SGLT-2Is and DPP-4Is on cardiovascular outcomes and cardiometabolic risk factors were reviewed. A total of 30 studies were included. Compared with DPP-4Is, SGLT-2Is treatment reduced the risk of stroke [risk ratio (RR) = 0.80; 95% confidence interval (CI), 0.76-0.84], myocardial infarction (RR = 0.85; 95% CI, 0.81-0.89), heart failure (RR = 0.58; 95% CI, 0.54-0.62), cardiovascular mortality (RR = 0.55; 95% CI, 0.51-0.60), and all-cause mortality (RR = 0.60; 95% CI, 0.57-0.63). In addition, SGLT-2Is presented favourable effects on hemoglobinA1c, fasting plasma glucose, systolic blood pressure, and diastolic blood pressure. The differences in blood lipids were also compared.

CONCLUSION

Sodium-glucose cotransporter-2 inhibitors are superior to DPP-4Is in terms of cardiovascular outcomes. Sodium-glucose cotransporter-2 inhibitors bring more benefits with respect to the cardiometabolic risk factors.

Mediterranean diet and endothelial function in patients with coronary heart disease: An analysis of the CORDIOPREV randomized controlled trial

BACKGROUND

Endothelial dysfunction is a crucial step in atherosclerosis development, and its severity is determinant for the risk of cardiovascular recurrence. Diet may be an effective strategy to protect the endothelium, although there is no consensus about the best dietary model. The CORonary Diet Intervention with Olive oil and cardiovascular PREVention (CORDIOPREV) study is an ongoing prospective, randomized, single-blind, controlled trial in 1,002 coronary heart disease (CHD) patients, whose primary objective is to compare the effect of 2 healthy dietary patterns (low-fat versus Mediterranean diet) on the incidence of cardiovascular events. Here, we report the results of one secondary outcome of the CORDIOPREV study: to evaluate the effect of these diets on endothelial function, assessed by flow-mediated dilation (FMD) of the brachial artery.

METHODS AND FINDINGS

From the total participants taking part in the CORDIOPREV study, 805 completed endothelial function study at baseline and were randomized to follow a Mediterranean diet (35% fat, 22% monounsaturated fatty acids [MUFAs], and <50% carbohydrates) or a low-fat diet (28% fat, 12% MUFAs, and >55% carbohydrates), with endothelial function measurement repeated after 1 year. As secondary objectives and to explore different underlying mechanisms in the modulation of endothelial function, we quantified endothelial microparticles (EMPs) and endothelial progenitor cells (EPCs) and evaluated, in 24 preselected patients, in vitro cellular processes related to endothelial damage (reactive oxygen species, apoptosis, and senescence) and endothelial repair (cell proliferation and angiogenesis), as well as other modulators (micro-RNAs [miRNAs] and proteins). Patients who followed the Mediterranean diet had higher FMD (3.83%; 95% confidence interval [CI]: 2.91-4.23) compared with those in the low-fat diet (1.16%; 95% CI: 0.80 to 1.98) with a difference between diets of 2.63% (95% CI: 1.89-3.40, p = 0.011), even in those patients with severe endothelial dysfunction. We observed higher EPC levels (group difference: 1.64%; 95% CI: 0.79-2.13, p = 0.028) and lower EMPs (group difference: -755 EMPs/μl; 95% CI: -1,010 to -567, p = 0.015) after the Mediterranean diet compared with the low-fat diet in all patients. We also observed lower intracellular reactive oxygen species (ROS) production (group difference: 11.1; 95% CI: 2.5 to 19.6, p = 0.010), cellular apoptosis (group difference: -20.2; 95% CI: -26.7 to -5.11, p = 0.013) and senescence (18.0; 95% CI: 3.57 to 25.1, p = 0.031), and higher cellular proliferation (group difference: 11.3; 95% CI: 4.51 to 13.5, p = 0.011) and angiogenesis (total master segments length, group difference: 549; 95% CI: 110 to 670, p = 0.022) after the Mediterranean diet than the low-fat diet. Each dietary intervention was associated with distinct changes in the epigenetic and proteomic factors that modulate biological process associated with endothelial dysfunction. The evaluation of endothelial function is a substudy of the CORDIOPREV study. As in any substudy, these results should be treated with caution, such as the potential for false positives because of the exploratory nature of the analyses.

CONCLUSIONS

Our results suggest that the Mediterranean diet better modulates endothelial function compared with a low-fat diet and is associated with a better balance of vascular homeostasis in CHD patients, even in those with severe endothelial dysfunction.

CLINICAL TRIAL REGISTRATION

URL, http://www.cordioprev.es/index.php/en. clinicaltrials.gov number NCT00924937.

Total antioxidant status reduction conditioned by a serum selenium concentration decrease as a mechanism of the ultrasonographically measured brachial artery dilatation impairment in patients with arterial hypertension

The objective of the study was to determine the relationship between serum concentrations of selenium (SeS) and zinc (ZnS), total antioxidant status (TAS) and endothelial function assessed by ultrasonographic method of dilatation of the brachial artery in 141 hypertensive patients. Patients with SeS < median were characterized by a statistically significantly lower flow-mediated dilation (FMD) than patients with SeS ≥ median. Patients with TAS < median were characterized by a significantly lower FMD than patients with TAS ≥ median. Older age, higher BMI, male gender, higher blood total cholesterol, ischemic heart disease, smoking and lower SeS constitute independent predictors of inferior endothelial function, expressed in lower FMD values. Smoking is an independent predictor of lower TAS, and the use of β-blockers and higher serum selenium levels are independent predictors of higher TAS. In summary, a decrease in TAS should be considered as a mechanism of inferior endothelial function in hypertensive patients conditioned by a decrease in SeS.

Markers of Subclinical Cardiovascular Disease in Patients with Adrenal Incidentaloma

Due to the growing availability of imaging examinations the percentage of patients with incidentally diagnosed adrenal tumors has increased. The vast majority of these lesions are benign, non-functioning adenomas, although according to various estimates even up to 30%-50% of patients with adrenal incidentaloma may present biochemical hypercortisolemia, without typical clinical features of Cushing's syndrome. Adrenal adenomas secreting small amounts of glucocorticoids may cause morphological and functional changes in the myocardium and blood vessels. Early stages of cardiovascular remodeling may be observed among asymptomatic patients with adrenal adenoma. Vascular changes precede the development of cardiovascular diseases and can increase morbidity and mortality in patients with adrenal incidentaloma. This risk may result not only from the traditional risk factors. Seemingly hormonally inactive adrenal tumors can indeed produce small amounts of glucocorticoids that have metabolic implications. Therefore, evaluation of patients with incidental adrenal findings presenting with subclinical cardiovascular disease seems of particular importance.

Endothelial Dysfunction and Advanced Glycation End Products in Patients with Newly Diagnosed Versus Established Diabetes: From the CORDIOPREV Study

Endothelial dysfunction and intima-media thickness of common carotid arteries (IMT-CC) are considered subclinical markers of atherosclerotic cardiovascular disease (ASCVD). Advanced glycation end products (AGEs) are increased in type 2 diabetes mellitus (T2DM) patients, compared with non-diabetics, being implicated in micro- and macrovascular complications. Our aim was to compare serum AGEs levels and subclinical atherosclerotic markers between patients with established and newly diagnosed T2DM. Among 540 patients with T2DM and coronary heart disease from the CORDIOPREV study, 350 patients had established T2DM and 190 patients had newly diagnosed T2DM. Serum levels of AGEs (methylglyoxal (MG) and N-carboxymethyl lysine (CML)) and subclinical atherosclerotic markers (brachial flow-mediated vasodilation (FMD) and IMT-CC) were measured. AGEs levels (all p < 0.001) and IMT-CC (p = 0.025) were higher in patients with established vs. newly diagnosed T2DM, whereas FMD did not differ between the two groups. Patients with established T2DM and severe endothelial dysfunction (i.e., FMD < 2%) had higher serum MG levels, IMT-CC, HOMA-IR and fasting insulin levels than those with newly diagnosed T2DM and non-severe endothelial dysfunction (i.e., FMD ≥ 2%) (all p < 0.05). Serum CML levels were greater in patients with established vs. newly diagnosed T2DM, regardless of endothelial dysfunction severity. Serum AGEs levels and IMT-CC were significantly higher in patients with established vs. newly diagnosed T2DM, highlighting the progressively increased risk of ASCVD in the course of T2DM. Establishing therapeutic strategies to reduce AGEs production and delay the onset of cardiovascular complications in newly diagnosed T2DM patients or minimize ASCVD risk in established T2DM patients is needed.

Effect of DPP-IV Inhibitors on Glycemic Variability in Patients with T2DM: A Systematic Review and Meta-Analysis

Glycemic variability (GV) has been an emerging target for preventing complications related to type 2 diabetes. For reducing GV, DPP-IV inhibitors have shown effectiveness compared to other oral anti-hyperglycemic drugs (OADs), but systematic evaluation has yet to be existed. A systematic review and meta-analysis of randomized controlled trials (RCTs) were performed to evaluate the effect of DPP-IV inhibitors compared with other OADs, on GV as measured by mean amplitude of glycemic excursions (MAGE). Searches were conducted using Pubmed, EMBASE, and the Cochrane Library, from which eligible studies were retrieved; seven RCTs were included in the analysis. DPP-IV inhibitors were found to significantly reduce MAGE compared to other OADs (mean difference = -14.61; 95% CI = -19.00 to -10.21; p < 0.0001) without significant heterogeneity among sulfonylureas (mean difference = -14.93; 95% CI = -21.60 to -8.26; p < 0.0001). Initial combination therapy with DPP-IV inhibitors more effectively reduced MAGE than stepwise add-on therapies (p = 0.006), although no differences in MAGE were found based on HbA1c values. These findings indicate that DPP-IV inhibitors are promising alternatives for reducing GV in type 2 diabetes patients. However, further studies utilizing larger numbers of patients and longer-term follow-ups are needed.

Endothelial Dysfunction in Chronic Heart Failure: Assessment, Findings, Significance, and Potential Therapeutic Targets

Chronic heart failure (CHF) is a complex syndrome that results from structural and functional disturbances that affect the ability of the heart to supply oxygen to tissues. It largely affects and reduces the patient's quality of life, socio-economic status, and imposes great costs on health care systems worldwide. Endothelial dysfunction (ED) is a newly discovered phenomenon that contributes greatly to the pathophysiology of numerous cardiovascular conditions and commonly co-exists with chronic heart failure. However, the literature lacks clarity as to which heart failure patients might be affected, its significance in CHF patients, and its reversibility with pharmacological and non-pharmacological means. This review will emphasize all these points and summarize them for future researchers interested in vascular pathophysiology in this particular patient population. It will help to direct future studies for better characterization of these two phenomena for the potential discovery of therapeutic targets that might reduce future morbidity and mortality in this "at risk" population.

Impaired Flow-Mediated Dilation and Severity and Vulnerability of Culprit Plaque in Patients with Coronary Artery Disease

The association between endothelial function, evaluated using flow-mediated dilatation (FMD), and the severity of coronary artery disease remains to be elucidated.A total of 245 consecutive patients with stable angina were prospectively enrolled. FMD was evaluated in the brachial artery before percutaneous coronary intervention. Patients were divided into 2 groups according to the FMD value (lower FMD group [FMD < 2.0], n = 82; higher FMD group [FMD ≥ 2.0], n = 163). The severity of coronary artery disease was evaluated using findings of angiography and optical coherence tomography, and compared between the 2 groups.The prevalence of left main (LM) disease was significantly higher in the lower FMD group than in the higher FMD group (8.5% versus 2.5%, P = 0.046), although the prevalence of multivessel disease was comparable between the groups. Lower FMD was independently associated with a higher prevalence of LM disease (odds ratio, 3.89; 95% confidence interval, 1.12-15.5; P = 0.033). A general linear model with multiple variables revealed that the minimal lumen area (MLA) in the culprit lesion was significantly smaller in patients with lower FMD than in those with higher FMD (regression coefficient b, -0.249 mm²; 95% confidence interval, -0.479--0.018 mm²; P = 0.035). The prevalence ofvulnerable plaque characteristics was comparable between the 2 groups.Patients with lower FMD had a higher incidence of LM disease and a smaller MLA in the culprit lesion. FMD may be a useful, noninvasive indicator for identifying patients with severe coronary artery disease.

Utility of the cold pressor test to predict future cardiovascular events

INTRODUCTION

The cold pressor test (CPT) is a common and extensively validated test, which induces systemic stress involving immersion of an individual's hand in ice water (normally temperature between 0 and 5 degrees Celsius) for a period of time. CPT has been used in various fields, like examining effects of stress on memory, decision-making, pain and cardiovascular health. Areas covered: In terms of cardiovascular health, current research is mainly interested in predicting the occurrence of cardiovascular (CV) events. The objective of this review is to give an overview of the history and methodology of the CPT, and clinical utility in possibly predicting CV events in CAD and other atherosclerotic diseases. Secondly, we will discuss possible future applications of the CPT in clinical care. Expert opinion: An important issue to address is the fact that the physiology of the CPT is not fully understood at this moment. As pointed out multiple mechanisms might be responsible for contributing to either coronary vasodilatation or coronary vasoconstriction. Regarding the physiological mechanism of the CPT and its effect on the measurements of the carotid artery reactivity even less is known.

Unacylated Ghrelin Improves Vascular Dysfunction and Attenuates Atherosclerosis during High-Fat Diet Consumption in Rodents

Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.

Delayed flow-mediated vasodilation and critical coronary stenosis

Endothelial dysfunction, wall thickening and plaque are progressive manifestations of atherosclerosis. Delayed or absent brachial artery dilation after ischemic stimulus has been associated with severity of extracoronary and coronary atherosclerosis. In the current study, we aimed to verify if delayed or absent dilation associates with critical coronary stenosis. We also evaluated the association between coronary stenosis, carotid artery wall thickness and peripheral artery disease. Endothelial function was investigated by flow-mediated dilation of the brachial artery up to 3 min after ischemia, and patients classified as early, late or no dilators. Coronary angiography was performed through transradial or femoral artery approach. Computerized quantitative angiography was used to obtain percent stenosis of all lesions, while the Gensini score was used to evaluate the severity of coronary atherosclerosis. Seventy-four patients were enrolled. Carotid wall thickness and plaque, and peripheral artery disease were detected by ultrasound. Subjects with critical coronary stenosis showed a higher prevalence of delayed or absent dilation (coronary stenosis ≥70 per cent: late dilators 50 per cent, no dilators 35 per cent; coronary stenosis ≤70 per cent : late dilators 27 per cent, no dilators 6 per cent). The Gensini score was progressively higher in late dilators and no dilators compared with early dilators (early: 4.5±13.5; late 17.5±27.1; no 39.7±55.0; P<0.02). Carotid atherosclerosis and peripheral artery disease were more prevalent in subjects with critical coronary stenosis. Delayed or absent dilation associates with coronary stenosis and different degree of coronary atherosclerosis. The kinetic of arterial dilation seems to be relevant as the magnitude of dilation.

Nocturnal Hypoglycemia in Type 2 Diabetes

Background and aims: It is known that the majority of critical unacknowledged hypoglycemia has an increased incidence in patients with type 1 diabetes (T1DM) with a long evolution. The aim of this research is to evaluate the variability of glucose level and hypoglycemic events in patients with type 2 diabetes (T2DM) having pharmacological interventions with hypoglycemic risk. These events are sometimes asymptomatic also in T2DM: frequently in elderly, patients with autonomic neuropathy, or having a long evolution of disease.

Material and method: This analysis includes 72 patients with T2DM, with a relative good metabolic control, and possible glucose fluctuations. Glucose variability was appreciated using continuous glucose monitoring systems (CGMS) used for more than 72 hours in hospital or ambulatory setting.

Results: The incidence, duration and severity of hypoglycemia are not correlated with HbA1c value, age, disease duration or treatment. Approximately a quarter of patients had nocturnal hypoglycemia and in 37,5% of events hypoglycemia was prolonged, more 45 minutes. Clinical manifestations in diurnal hypoglycemia were presents in only 40% of the recorded events.

Conclusions: The study suggested that CGMS is beneficial for patients with type 2 diabetes, with hypoglycemic risk and complications, to adjusted medication, education and prevention the cardiovascular events.

Mediterranean diet improves endothelial function in patients with diabetes and prediabetes: A report from the CORDIOPREV study

BACKGROUND AND AIMS

Endothelial dysfunction (ED) plays a key role in the development of atherosclerotic cardiovascular disease (ASCVD). Likewise, type 2 diabetes (T2D) is a major CVD risk factor. Therefore, our objective was to explore whether long-term consumption of a Mediterranean diet (MedDiet) rich in olive oil or a low-fat diet (LF diet) was associated with an improvement in ED and whether the potential benefits were similar in patients with or without T2D in the CORDIOPREV clinical trial (NCT00924937).

METHODS

Endothelial function was measured in 805 participants who had completed follow-up ultrasound image studies, using ultrasonography of brachial artery to calculate flow mediated vasodilatation (FMD) before and after 1.5 years of intervention with a MedDiet [35% of calories from fat (22% monounsaturated) and 50% from carbohydrates] and LF diet [28% fat (12% monounsaturated) and 55% of calories from carbohydrates]. We categorized participants as patients with T2D, prediabetes, and without T2D according to the American Diabetes Association (ADA) criteria.

RESULTS

MedDiet increased FMD in patients with T2D [5.2 ± 0.4 at 1.5 years vs. 3.8 ± 0.4 at baseline; p=0.04] and prediabetes [4.9 ± 0.4 vs. 3.8 ± 0.4; p=0.04] and induced an improvement in FMD compared to LF diet in patients with diabetes [5.2 ± 0.4 (MedDiet) vs.3.7 ± 0.4 (LF diet); p=0.01]; whereas both diets maintained FMD stable in patients without diabetes.

CONCLUSIONS

Habitual consumption of a MedDiet rich in extra virgin olive oil improves endothelial function in patients with prediabetes and diabetes. This takes great importance given that diet must be the cornerstone of treatment of patients with diabetes at high cardiovascular risk.

Estradiol Regulates Txnip and Prevents Intermittent Hypoxia-Induced Vascular Injury

Chronic intermittent hypoxia (IH) contributes to obstructive sleep apnea (OSA)-related cardiovascular diseases through increasing oxidative stress. It has been widely recognized that estradiol decreases the risk for cardiovascular disease, but the estrogen replacement therapy is limited for its side effects. Thioredoxin (Trx) and its endogenous inhibitor, thioredoxin-interacting protein (Txnip), are associated with the protective effect of estradiol in some conditions. In this study, we aimed to explore whether estradiol could protect against IH-induced vascular injury, and the possible effect of Trx-1/Txnip in this process. Forty-eight adult female C57/BL6J mice were randomly divided into 4 groups, ovariectomy combined with IH group, sham operation combined with IH group, IH group and the control group. The mice treated with IH for 8 hrs/day, and 28 days. IH induced the injury of aorta, and ovariectomized mice were more prone to the IH-induced aortic injury, with higher level of oxidative stress. In vitro, estradiol increased Trx-1 level, but decreased the level of Txnip and oxidative stress in human umbilical vein endothelial cells (HUVECs) treated with IH for 16 hrs. Knock-down of Txnip by specific siRNA rescued oxidative stress and apoptosis. In conclusion, estradiol protects against IH-induced vascular injury, partially through the regulation of Trx-1/Txnip pathway.

Methods to evaluate arterial structure and function in children - State-of-the art knowledge

BACKGROUND

With increasing rates of hypertension, obesity, and diabetes in the pediatric population, wide available, and reproducible methods are necessary to evaluate arterial structure and function in children and adolescents.

METHODS

MEDLINE/Pubmed was searched for articles published in years 2012-2017 on methodology of, current knowledge on, and limitations of the most commonly used methods to evaluate central, proximal and coronary arteries, as well as endothelial function in pediatric patients.

RESULTS

Among 1528 records screened (including 1475 records from years 2012 to 2017) 139 papers were found suitable for the review. Following methods were discussed in this review article: ultrasound measurements of the intima-media thickness, coronary calcium scoring using computed tomography, arterial stiffness measurements (pulse wave velocity and pulse wave analysis, carotid artery distensibility, pulse pressure, and ambulatory arterial stiffness index), ankle-brachial index, and methods to evaluate vascular endothelial function (flow-mediated vasodilation, peripheral arterial tonometry, Doppler laser flowmetry, and cellular and soluble markers of endothelial dysfunction).

CONCLUSIONS

Ultrasonographic measurement of carotid intima-media thickness and measurement of pulse wave velocity (by oscillometry or applanation tonometry) are highly reproducible methods applicable for both research and clinical practice with proved applicability for children aged ≥6 years or with height ≥120cm. Evaluation of ambulatory arterial stiffness index by ambulatory blood pressure monitoring is another promising option in pediatric high-risk patients. Clearly, further studies are necessary to evaluate usefulness of these and other methods for the detection of subclinical arterial damage in children.

A randomized controlled trial comparing the effects of dapagliflozin and DPP-4 inhibitors on glucose variability and metabolic parameters in patients with type 2 diabetes mellitus on insulin

BACKGROUND

Dipeptidyl peptidase-4 (DPP-4) inhibitors and sodium-glucose co-transporter 2 (SGLT2) inhibitors improve hyperglycemia, and the usefulness of co-administration of DPP-4 inhibitors and insulin therapy has been well established. However, it has been still uncertain whether combination therapy of SGLT2 inhibitors and insulin is superior to that of DPP-4 inhibitors and the latter. Therefore, we investigated the superiority of dapagliflozin on glucose fluctuation compared with DPP-4 inhibitors in patients with type 2 diabetes mellitus (T2DM) on insulin using a continuous glucose monitoring (CGM) system.

METHODS

In this prospective, randomized, open-label controlled trial, 36 patients with T2DM and treated with DPP-4 inhibitors and insulin therapy, were enrolled and allocated into two groups. The patients either switched their DPP-4 inhibitors to dapagliflozin 5 mg for 12 weeks, or continued their DPP-4 inhibitors for the same period. CGM analyses and metabolic markers were assessed before and after treatment periods.

RESULTS

In total, data from 29 patients were analyzed. There were no significant differences in the mean amplitude of glycemic excursions and other CGM profiles in either group after treatment. Within the dapagliflozin treatment group, significant reductions of body mass index and albuminuria, and increases of HbA1c, hemoglobin and hematocrit were observed, but improvement of albuminuria was not significant if compared with the DPP-4 continuation group.

CONCLUSIONS

Combination therapy of dapagliflozin and insulin was not superior in glucose fluctuation to DPP-4 inhibitors on insulin. However, dapagliflozin may in part provide favorable effects on metabolism in patients with T2DM treated with insulin therapy. Trial registration UMIN-CTR: UMIN000015033. Registered 2 September 2014.

A Mediterranean diet lowers blood pressure and improves endothelial function: results from the MedLey randomized intervention trial

Background: The consumption of a Mediterranean diet (MedDiet) is associated with a lower risk of cardiovascular disease. However, its impact on blood pressure and endothelial function is not clear.Objective: We sought to determine the effects of adhering to the consumption of a MedDiet for 6 mo on blood pressure and endothelial function in older, healthy Australians.Design: A total of 166 men and women aged >64 y were allocated via minimization to consume either a MedDiet (n = 85) or their habitual diet (HabDiet; control: n = 81) for 6 mo. The MedDiet comprised mainly plant foods, abundant extra-virgin olive oil, and minimal red meat and processed foods. A total of 152 participants commenced the study, and 137 subjects completed the study. Home blood pressure was measured on 5 consecutive days at baseline (n = 149) and at 3 and 6 mo. Endothelial function (n = 82) was assessed by flow-meditated dilatation (FMD) at baseline and 6 mo. Dietary intake was monitored with the use of 3-d weighed food records. Data were analyzed with the use of linear mixed-effects models to determine adjusted between-group differences.Results: The MedDiet adherence score increased significantly in the MedDiet group but not in the HabDiet group (P < 0.001). The MedDiet, compared with the HabDiet, resulted in lower systolic blood pressure (P-diet × time interaction = 0.02) [mean: -1.3 mm Hg (95% CI: -2.2, -0.3 mm Hg; P = 0.008) at 3 mo and -1.1 mm Hg (95% CI: -2.0, -0.1 mm Hg; P = 0.03) at 6 mo]. At 6 mo, the percentage of FMD was higher by 1.3% (95% CI: 0.2%, 2.4%; P = 0.026) in the MedDiet group.Conclusion: Australian men and women who consumed a MedDiet for 6 mo had small but significantly lower systolic blood pressure and improved endothelial function. This trial was registered at www.anzctr.org.au as ACTRN12613000602729.

Obesity, arterial function and arterial structure - a systematic review and meta-analysis

OBJECTIVE

Obesity is an established risk factor for cardiovascular disease. The mechanisms by which obesity affects cardiovascular risk have not been fully elucidated. This paper reports a comprehensive systematic review and meta-analysis on obesity and two key aspects of vascular health using gold-standard non-invasive measures - arterial endothelial function (brachial flow-mediated dilatation) and subclinical atherosclerosis (carotid intima-media thickness).

METHODS

Electronic searches for 'Obesity and flow-mediated dilatation' and 'Obesity and intima-media thickness' were performed using Ovid Medline and Embase databases. A meta-analysis was undertaken for brachial flow-mediated dilatation and carotid intima-media thickness to obtain pooled estimates for adults with obesity and those with healthy weight.

RESULTS

Of the 5,810 articles retrieved, 19 studies on flow-mediated dilatation and 19 studies on intima-media thickness were included. Meta-analysis demonstrated that obesity was associated with lower flow-mediated dilatation (-1.92 % [95% CI -2.92, -0.92], P = 0.0002) and greater carotid intima-media thickness (0.07 mm [95% CI 0.05, 0.08], P < 0.0001).

CONCLUSIONS

Obesity is associated with poorer arterial endothelial function and increased subclinical atherosclerosis, consistent with these aspects of vascular health at least partially contributing to the increased risk of cardiovascular events in adults with obesity. These estimated effect sizes will enable vascular health benefits in response to weight loss treatment to be put in greater perspective, both in the research setting and potentially also clinical practice.

Imaging Subclinical Atherosclerosis: Where Do We Stand?

The age of initiation and the rate of progression of atherosclerosis vary markedly among individuals and have been difficult to predict with traditional cardiovascular risk assessment models. Although these risk models provide good discrimination and calibration in certain populations, cardiovascular disease (CVD) risk may not be accurately estimated in low- and intermediate risk individuals. Therefore, imaging techniques such as Ankle-Brachial Index (ABI), Coronary Artery Calcium score (CAC), carotid Intima-Media Thickness (cIMT), flow mediated dilation (FMD) and Positron Emission Tomography (PET) have been developed and used to reclassify these individuals. In the present article we review the role of the most commonly used imaging techniques for CVD risk assessment.

Long term evolution of endothelial function during kidney transplantation

Background

Endothelial dysfunction is an important precursor to the development of atherosclerosis, and has been suggested to play a role in the increased cardiovascular risk in patients with end stage renal disease. Endothelial function improves rapidly following post kidney transplantation, but the long term change remains unclear. Hypothesizing that endothelial function would remain improved long term post kidney transplantation, we evaluated the longitudinal change of endothelial function, measured by flow-mediated dilation (FMD) of the brachial artery, from months 1 to 24 post transplantation. Given the previously reported association of fibroblast growth factor 23 (FGF-23) with endothelial dysfunction, we also examined changes in the association between FGF-23 levels and the change in FMD following kidney transplantation.

Methods

We performed a prospective cohort study of 149 kidney transplant recipients, measuring endothelial function by FMD at months 1, 12, and 24 post-transplant. FGF-23 levels were measured at months 1 and 24 post-transplant. Linear mixed effects models were used to assess both the unadjusted and adjusted outcomes.

Results

The cohort (mean age 49 ± 13 years) was 74 % male and 75 % white. The median FMD was 6.3 % (IQR: 3.4, 10.2), 5.4 % (IQR: 3.1, 8.5), and 5.6 % (IQR: 3.5, 9.1) at 1, 12, and 24 months, respectively. After adjustment for covariates, compared to month 1, no change occurred in FMD at 12 months (−0.66 %; 95 % CI: −1.81 %, 0.49 %; P = 0.262) or 24 months (−0.25 %; 95%CI: −1.76 %, 1.26 %; P = 0.746). FGF-23 decreased significantly over time (P = 0.024), but there was no significant association between FGF-23 and FMD (P = 0.799).

Conclusion

Endothelial function remained stable at 12 and 24 months from 1 month post-kidney transplant, indicating that the improved endothelial function seen with transplant is maintained up to 2 years post transplantation. There was also no significant association between FGF-23 and endothelial function following kidney transplantation.

Relationship of sonographic wall components of the brachial artery to hypertension and coronary atherosclerosis

The aim of this study was to determine whether sonographically assessed intimal (echodense, ED) or medial (echolucent, EL) thickening of the brachial artery is associated with coronary artery disease (CAD) and/or arterial hypertension (HT). In 201 patients the ED and EL wall components, as well as the total wall thickness of the brachial artery, were measured with high-resolution ultrasound (13 MHz). According to the presence or absence of CAD and HT, the patients were divided into four groups: no HT and no CAD (n = 26, group 1), CAD (≥30% diameter stenosis in ≥1 major branch) only (n = 63, group 2), HT only (n = 34, group 3), and HT and CAD (n = 78, group 4). EL ( p < 0.001) and combined wall thickness ( p < 0.001), but not the ED wall component, were significantly different between the groups, with the highest values occurring in group 4. On logistic regression analyses adjusting for age, coronary risk factors and body mass index, EL, but not ED, thickness correlated independently with the presence of CAD (p = 0.04) and HT ( p < 0.001). High-resolution ultrasound examination of the brachial artery wall structure may contribute to the noninvasive assessment of early atherosclerosis.

Association of improvement of brachial artery flow-mediated vasodilation with cardiovascular events

The aim of this pilot study was to test the prognostic value of serial measurements of peripheral endothelial function, assessed by brachial artery flow-mediated dilation (FMD), in patients with angiographically proven coronary artery disease. In 68 patients, FMD was measured on the day after coronary angiography and again after a mean of 14 ± 12 months. Patients were divided into two groups: absolute improvement in FMD ≥ 3% (FMD-improver += FMD-i) and <3% (FMD-non-improver = FMD-ni). After a mean follow-up of 44 ± 12 months, cardiovascular events were recorded. Baseline characteristics were similar between groups, except the number of risk factors which was smaller in FMD-i (1.6 ± 0.7 vs 2.1 ± 0.9, p < 0.02). Cardiovascular events were more frequent in FMD-ni (9 vs 1 event; p < 0.05). In Kaplan–Meier analysis, a trend towards a better outcome in patients with improved FMD was found using the log-rank test (p = 0.08). The single baseline FMD showed no relationship with late cardiovascular events. Thus, ‘delta-FMD’ may be more closely related to prognosis than a single FMD measurement.

American Society of Echocardiography Report

Noninvasive measures of atherosclerosis have emerged as adjuncts to standard cardiovascular disease (CVD) risk factors in an attempt to refine risk stratification and the need for more aggressive preventive strategies. Two such approaches, carotid artery imaging and brachial artery reactivity testing (BART), are ultrasound based. Numerous carotid artery imaging protocols have been used, and methodologic aspects are described in detail in this review. The panel recommends that protocols: (1) use end-diastolic (minimum dimension) images for intimal-medial thickness (IMT) measurements; (2) provide separate categorization of plaque presence and IMT; (3) avoid use of a single upper limit of normal for IMT because the measure varies with age, sex, and race; and (4) incorporate lumen measurement, particularly when serial measurements are performed to account for changes in distending pressure. Protocols may vary in the number of segments wherein IMT is measured, whether near wall is measured in addition to far wall, and whether IMT measurements are derived from B-mode or M-mode images, depending on the application. BART is a technique that requires meticulous attention to patient preparation and methodologic detail. Its application is substantially more challenging than is carotid imaging and remains largely a research technique that is not readily translated into routine clinical practice.

Peripheral endothelial function may predict the effectiveness of beta-blocker therapy in patients with idiopathic dilated cardiomyopathy

OBJECTIVES

Beta-blockers have improved the prognosis of patients with dilated cardiomyopathy as they improve left ventricular (LV) systolic function and structure, which are crucial for myocardial recovery. However, to date, no accurate methods can predict the effectiveness of β-blocker therapy. Our goal was to evaluate whether peripheral endothelial function could be a useful predictor for β-blocker responses and related LV reverse remodeling (LVRR) in patients with idiopathic dilated cardiomyopathy (IDC).

METHODS

Fifty-two IDC patients were recruited and underwent brachial artery flow-mediated dilation (FMD). Beta-blockers were titrated to doses tolerable for each patient. LV function and structure were measured by echocardiography. A positive response to β-blockers was defined as an increase of ≥10% in LV ejection fraction (LVEF). LVRR was defined as an increase of ≥10% in LVEF and a decrease of ≥15% in LV end-systolic volume (LVESV).

RESULTS

Baseline FMD was 8.4±3.0% in IDC patients and significantly lower than healthy controls. At three-month follow-up, 54% of patients had a positive β-blocker response and 40% achieved LVRR. Patients with a positive response to β-blockers or with LVRR had significantly higher baseline FMD values than those without. FMD was the most significant predictor of changes in LVEF and LVESV. The sensitivity and specificity of baseline FMD to predict β-blocker responses was 64.3% and 83.3%, respectively, and to predict LVRR was 61.9% and 80.6%, respectively. Beta-blockers themselves did not influence FMD values.

CONCLUSIONS

FMD could serve as an independent predictor for monitoring β-blocker therapy effectiveness in IDC patients.

Prognostic Value of Flow-Mediated Vasodilation in Brachial Artery and Fingertip Artery for Cardiovascular Events: A Systematic Review and Meta-Analysis

BACKGROUND

Endothelial dysfunction plays a pivotal role in cardiovascular disease progression, and is associated with adverse events. The purpose of this systematic review and meta-analysis was to investigate the prognostic magnitude of noninvasive peripheral endothelial function tests, brachial artery flow-mediated dilation (FMD), and reactive hyperemia--peripheral arterial tonometry (RH-PAT) for future cardiovascular events.

METHODS AND RESULTS

Databases of MEDLINE, EMBASE, and the Cochrane Library were systematically searched. Clinical studies reporting the predictive value of FMD or RH-PAT for cardiovascular events were identified. Two authors selected studies and extracted data independently. Pooled effects were calculated as risk ratio (RR) for continuous value of FMD and natural logarithm of RH-PAT index (Ln_RHI) using random-effects models. Thirty-five FMD studies of 17 280 participants and 6 RH-PAT studies of 1602 participants were included in the meta-analysis. Both endothelial function tests significantly predicted cardiovascular events (adjusted relative risk [95% CI]: 1% increase in FMD 0.88 [0.84-0.91], P<0.001, 0.1 increase in Ln_RHI 0.79 [0.71-0.87], P<0.001). There was significant heterogeneity in the magnitude of the association across studies. The magnitude of the prognostic value in cardiovascular disease subjects was comparable between these 2 methods; a 1 SD worsening in endothelial function was associated with doubled cardiovascular risk.

CONCLUSIONS

Noninvasive peripheral endothelial function tests, FMD and RH-PAT, significantly predicted cardiovascular events, with similar prognostic magnitude. Further research is required to determine whether the prognostic values of these 2 methods are independent of each other and whether an endothelial function-guided strategy can provide benefit in improving cardiovascular outcomes.

Further Peripheral Vascular Dysfunction in Heart Failure Patients With a Continuous-Flow Left Ventricular Assist Device: The Role of Pulsatility

OBJECTIVES

Using flow-mediated vasodilation (FMD) and reactive hyperemia (RH), this study aimed to provide greater insight into left ventricular assist device (LVAD)-induced changes in peripheral vascular function.

BACKGROUND

Peripheral endothelial function is recognized to be impaired in patients with heart failure with reduced ejection fraction (HFrEF), but the peripheral vascular effects of continuous-flow LVAD implantation, now used as either a bridge to transplantation or as a destination therapy, remain unclear.

METHODS

Sixty-eight subjects (13 New York Heart Association [NYHA] functional class II HFrEF patients, 19 NYHA functional class III/IV HFrEF patients, 20 NYHA functional class III/IV HFrEF patients post-LVAD implantation, and 16 healthy age-matched control subjects) underwent FMD and RH testing in the brachial artery with blood flow velocity, artery diameters, and pulsatility index (PI) assessed by ultrasound Doppler.

RESULTS

PI was significantly lower in the LVAD group (2.0 ± 0.4) compared with both the HFrEF II (8.6 ± 0.8) and HFrEF III/IV (8.1 ± 0.9) patients, who, in turn, had significantly lower PI than the control subjects (12.8 ± 0.9). Likewise, LVAD %FMD/shear rate (0.09 ± 0.01 %Δ/s(-1)) was significantly reduced compared with all other groups (control subjects, 0.24 ± 0.03; HFrEF II, 0.17 ± 0.02; and HFrEF III/IV, 0.13 ± 0.02 %Δ/s(-1)), and %FMD/shear rate significantly correlated with PI (r = 0.45). RH was unremarkable across groups.

CONCLUSIONS

Although central hemodynamics are improved in patients with HFrEF by a continuous-flow LVAD, peripheral vascular function is further compromised, which is likely due, at least in part, to the reduction in pulsatility that is a characteristic of such a mechanical assist device.

Assessment of endothelial function. History, methodological aspects, and clinical perspectives

In 1986, endothelial function was measured for the first time in patients with atherosclerotic coronary arteries. Since then, several methods for assessment of endothelial function, such as endothelium-dependent vasodilation induced by intra-arterial infusion of vasoactive agents using coronary angiography, Doppler flow guide wire, mercury-filled Silastic strain-gauge plethysmography, flow-mediated vasodilation, reactive hyperemia-peripheral arterial tonometry, and vascular response using an oscillometric method have been performed in humans. This review focuses on the assessment of endothelial function, including measurement history, methodological issues, and clinical perspectives.

Measurement of arterial stiffness in subjects with and without renal disease: Are changes in the vessel wall earlier and more sensitive markers of cardiovascular disease than intima media thickness and pulse pressure?

There is increased cardiovascular (CV) mortality in subjects with chronic kidney disease (CKD). Arterial stiffness in these subjects is increased when compared to a healthy population. Markers of arterial stiffness and intima media thickness (IMT) are predictors of CV mortality. The aim of this study was to investigate whether there is any difference in markers of arterial stiffness and IMT between subjects with normal renal function and those with mild renal disease. The arterial distension waveform, IMT, diameter, and brachial blood pressure were measured to calculate Young's modulus (E) and elastic modulus (Ep) in the common carotid arteries of subjects with normal kidney function (estimated glomerular filtration rate [eGFR] >90) and those mild CKD (stage 2, eGFR 89–60). Data were available for 15 patients with normal kidney function and 29 patients with mild CKD. The subjects with mild CKD were older, but other co-variables were not significantly different. Both arterial wall stiffness parameters (E and Ep), but not IMT were significantly higher in the mild CKD group. Logistic regression demonstrated that only the arterial wall stiffness parameters (Ep and E) were independently associated with mild renal disease compared with normal, in a model adjusting for sex, age and diabetes and history of cardiovascular disease (CVD). E and Ep may be early markers of CVD in subjects with mild CKD that may manifest change before other more recognized markers such as IMT and pulse pressure.

Analysis of Carotid Ultrasound Findings on Cardiovascular Events in Patients with Coronary Artery Disease during Seven-Year Follow-Up

BACKGROUND AND OBJECTIVES

Both carotid intima-media thickness (CIMT) and carotid plaque are important factors in the primary prevention of cardiac disease. However, it is unclear which one is more important for prognosis, especially in patients with coronary artery disease (CAD).

SUBJECTS AND METHODS

In total, 1426 consecutive CAD patients, proven by angiography, were followed-up for a mean of 85 months. The study population was divided into four groups depending on the CIMT (≥0.83 mm, >95 percentile in Korea) and the presence or absence of carotid plaque.

RESULTS

Patients with carotid plaque and thick CIMT (n=237, 16.6%) had a higher prevalence of hypertension, diabetes mellitus, and dyslipidemia than those had plaque and thin CIMT (n=213, 14.9%), those without plaque and thick CIMT (n=265, 18.6%) and those without plaque and thin CIMT (n=711, 49.9%). The patients with carotid plaque and thick CIMT group had a higher cardiac mortality rate (20.7% vs. 13.1%, 9.4% and 3.9%, respectively, p<0.001) and higher major adverse cardiovascular events (MACE) including death, acute myocardial infarction, and stroke (27.8% vs. 18.8%, 15.5% and 9.3%, respectively, p<0.001) than any other groups. Multivariate Cox regression analysis showed that the presence of carotid plaque with thick CIMT had the highest hazard ratio (HR) compared to other groups (HR 2.23 vs. 1.81, 2.01) for cardiac mortality. Also, carotid plaque had a higher HR than CIMT for mortality (HR 1.56 vs. 1.37) and MACE (HR 1.54 vs. 1.36) in the total study population.

CONCLUSION

Carotid plaque is a more important prognostic factor than CIMT in patients with CAD, and adding a thick CIMT to carotid plaque increases the prognostic power for cardiac events.

Tetrahydrobiopterin improves endothelial function in cardiovascular disease: a systematic review

Background. Tetrahydrobiopterin (BH4) is a cofactor of nitric oxide synthase (NOS). Nitric oxide (NO) bioavailability is reduced during the early stage of vascular diseases, such as coronary artery disease, hypercholesterolemia, hypertension, and diabetic vasculopathy, and even throughout the entire progression of atherosclerosis. Methods. A literature search was performed using electronic databases (up to January 31, 2014), including MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL), using an established strategy. Results. Fourteen articles were selected with a total of 370 patients. Ten of the fourteen studies showed a significant improvement in the endothelial dysfunction of various cardiovascular disease groups with BH4 supplementation compared with the control groups or placebos. Three studies showed no positive outcome, and one study showed that low-dose BH4 had no effect but that high-dose BH4 did have a significantly different result. Conclusions. This review concludes that supplementation with BH4 and/or augmentation of the endogenous levels of BH4 will be a novel approach to improve the endothelial dysfunction observed in various cardiovascular diseases. BH4 might be considered to be a new therapeutic agent to prevent the initiation and progression of cardiovascular disease.

A select review reporting the quality of studies measuring endothelial dysfunction in randomised diet intervention trials

A quality assessment of the primary studies reported in the literature carried out using select dietary ingredients (DI) purported to affect vascular endothelial function was conducted through a systematic PubMed search from January 2000 to August 2012. A total of seventy randomised controlled trials with defined DI (folic acid (fifteen), n-3 fatty acids (twenty), cocoa (fifteen) and isoflavones (twenty)) and standardised measures of vascular endothelial function were evaluated. Jadad scores, quality scoring parameters for DI and flow-mediated dilation (FMD) methodology used were ascertained. A total of 3959 randomised subjects, mean age 51 (se 0·21) years (range 9-79 years), were represented in the dataset. The mean Jadad scores did not differ statistically among the DI studies, with the majority of the studies being of good quality. Higher DI quality scores were achieved by studies using the botanical ingredients cocoa and isoflavones than by those using the nutrient ingredients folic acid and n-3 fatty acids. The mean DI quality scores were 4·13 (se 0·34), 5·20 (se 0·47), 6·13 (se 0·41) and 6·00 (se 0·59) for the folic acid, n-3 fatty acid, cocoa and isoflavone intervention studies, respectively (and significantly different). The mean Corretti FMD scores were 7·27 (se 0·56), 7·46 (se 0·79), 6·29 (se 0·61) and 7·11 (se 0·56) for the folic acid, n-3 fatty acid, cocoa and isoflavone intervention studies, respectively (NS). FMD studies failed to adequately describe the equipment used and more than half failed to provide an adequate description of the procedures used for vascular image acquisition and measurement. DI can be utilised for dietary intervention studies; however, the methodology should be clearly reported using the guidelines for assessment for both DI and FMD.

Endothelial dysfunction is associated with major adverse cardiovascular events in peritoneal dialysis patients

Endothelial dysfunction is implicated in increased cardiovascular risk in nondialyzed population. However, the prognostic impact of endothelial dysfunction on cardiovascular outcome has not been investigated in peritoneal dialysis (PD) patients. We prospectively determined endothelial function by brachial artery endothelium-dependent vasodilation (flow-mediated dilation [FMD]) in 143 nondiabetic PD patients and 32 controls. Primary outcome was a major adverse cardiac and cerebrovascular event (MACCE). Brachial FMD was significantly lower in PD patients than in controls (2.9% [1.3-4.7] vs 6.2% [5.4-8.3], P < 0.001). During a mean follow-up of 42 months, primary outcome was observed in 25 patients (17.5%). When patients were dichotomized by the median value of FMD (2.9%), incidence rates of MACCEs were significantly higher in the group with lower FMD compared with higher FMD (7.2 vs 3.0/100 person-years, P = 0.03). In multivariate Cox analysis, low FMD (≤2.9%) was a significant independent predictor of MACCEs (hazard ratio = 2.73, 95% confidence interval = 1.03-7.22, P = 0.04). Furthermore, multivariate fractional polynomial analysis showed that the risk of MACCE decreased steadily with higher FMD values. Impaired brachial FMD was a significant independent predictor of MACCEs in PD patients. Estimating endothelial dysfunction by brachial FMD could be useful for stratifying cardiovascular risk in these patients.

Brachial artery reactivity and vascular reactive hyperemia for preoperative anaesthesia risk assessment - an observational study

Background

Non-invasive measures of vascular reactivity have emerged to refine cardiovascular risk. However, limited data exists investigating vascular reactivity as a preoperative diagnostic tool for anesthesiologists. In this study, we compare the utility of two non-invasive techniques, Brachial Artery Reactivity Testing (BART) and Digital Thermal Monitoring (DTM), as surrogates for measuring vascular reactivity.

Methods

Following IRB approval, 26 patients scheduled for major thoracic surgery (e.g. esophagectomy and pneumonectomy) were studied prospectively. BART [Flow mediated dilation (FMD) and Peak flow velocity (PFV)] and DTM [Temperature rebound (TR%)] were performed preoperatively at baseline using 5 minute blood pressure cuff occlusion of the upper arm. Statistical summaries were provided for the comparison of BART and DTM with select patient characteristics, and correlations were used to investigate the strength of the relationship between BART and DTM measurements.

Results

Patients preoperatively diagnosed with hyperlipidemia were associated with lower FMD% values {Median (Range): 14.8 (2.3, 38.1) vs. 6.2 (0.0, 14.3); p = 0.006}. There were no significant associations between BART and DTM techniques in relation to cardiovascular risk factors or postoperative complications.

Conclusion

Our study suggests that impaired vascular reactivity as measured by BART is associated with the incidence of hyperlipidemia. Also, using a novel technique such as DTM may provide a simpler and more accessible point of care testing for vascular reactivity in a perioperative setting. Both non-invasive techniques assessing vascular function warrant further refinement to better assist preoperative optimization strategies aimed at improving perioperative vascular function.

Effect of periodontal therapy on arterial structure and function among aboriginal australians: a randomized, controlled trial

Observational studies and nonrandomized trials support an association between periodontal disease and atherosclerotic vascular disease. Both diseases occur frequently in Aboriginal Australians. We hypothesized that nonsurgical periodontal therapy would improve measures of arterial function and structure that are subclinical indicators of atherosclerotic vascular disease. This parallel-group, randomized, open label clinical trial enrolled 273 Aboriginal Australians aged ≥18 years with periodontitis. Intervention participants received full-mouth periodontal scaling during a single visit, whereas controls received no treatment. Prespecified primary end points measured 12-month change in carotid intima-media thickness, an indicator of arterial structure, and 3- and 12-month change in pulse wave velocity, an indicator of arterial function. ANCOVA used complete case data to evaluate treatment group differences. End points could be calculated for 169 participants with follow-up data at 3 months and 168 participants at 12 months. Intima-media thickness decreased significantly after 12 months in the intervention group (mean reduction=-0.023 [95% confidence interval {CI}, -0.038 to -0.008] mm) but not in the control group (mean increase=0.002 [95% CI, -0.017 to 0.022] mm). The difference in intima-media thickness change between treatment groups was statistically significant (-0.026 [95% CI, -0.048 to -0.003] mm; P=0.03). In contrast, there were no significant differences between treatment groups in pulse wave velocity at 3 months (mean difference, 0.06 [95% CI, -0.17 to 0.29] m/s; P=0.594) or 12 months (mean difference, 0.21 [95% CI, -0.01 to 0.43] m/s; P=0.062). Periodontal therapy reduced subclinical arterial thickness but not function in Aboriginal Australians with periodontal disease, suggesting periodontal disease and atherosclerosis are significantly associated.

Endothelial dysfunction in conduit arteries and in microcirculation. Novel therapeutic approaches

The vascular endothelium not only is a single monolayer of cells between the vessel lumen and the intimal wall, but also plays an important role by controlling vascular function and structure mainly via the production of nitric oxide (NO). The so called "cardiovascular risk factors" are associated with endothelial dysfunction, that reduces NO bioavailability, increases oxidative stress, and promotes inflammation contributing therefore to the development of atherosclerosis. The significant role of endothelial dysfunction in the development of atherosclerosis emphasizes the need for efficient therapeutic interventions. During the last years statins, angiotensin-converting enzyme inhibitors, angiotensin-receptor antagonists, antioxidants, beta-blockers and insulin sensitizers have been evaluated for their ability to restore endothelial function (Briasoulis et al., 2012). As there is not a straightforward relationship between therapeutic interventions and improvement of endothelial function but rather a complicated interrelationship between multiple cellular and sub-cellular targets, research has been focused on the understanding of the underlying mechanisms. Moreover, the development of novel diagnostic invasive and non-invasive methods has allowed the early detection of endothelial dysfunction expanding the role of therapeutic interventions and our knowledge. In the current review we present the available data concerning the contribution of endothelial dysfunction to atherogenesis and review the methods that assess endothelial function with a view to understand the multiple targets of therapeutic interventions. Finally we focus on the classic and novel therapeutic approaches aiming to improve endothelial dysfunction and the underlying mechanisms.

A meta-analysis of randomized controlled trials of telmisartan for flow-mediated dilatation

There have been a number of small-sized underpowered randomized controlled trials to assess effects of telmisartan on flow-mediated dilatation (FMD). To determine whether telmisartan increases FMD, we performed a meta-analysis of these trials. MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were searched through December 2013. Eligible studies were prospective randomized controlled trials of telmisartan reporting FMD as an outcome. Search terms included: telmisartan; endothelial function/dysfunction; flow-mediated dilation/dilatation/vasodilation/vasodilatation; and randomized, randomly or randomization. Included studies were reviewed to determine the number of patients randomized, mean duration of treatment and percent changes of FMD. Of 25 potentially relevant articles screened initially, seven reports of randomized trials enrolling a total of 398 patients were identified and included. A pooled analysis of the seven trials demonstrated a statistically significant increase in FMD by 48.7%, with telmisartan relative to control in the random-effects model (mean difference, 48.72%; 95% confidence interval, 15.37-82.08%; P for effect=0.004; P for heterogeneity <0.00001). Exclusion of any single trial from the analysis did not substantively alter the overall result of our analysis. There was no evidence of significant publication bias. In conclusion, the present meta-analysis of seven randomized controlled trials enrolling a total of 398 patients confirmed the evidence of a significant increase in FMD with telmisartan, which suggests that telmisartan may improve endothelial dysfunction.

Non-invasive endothelial function testing and the risk of adverse outcomes: a systematic review and meta-analysis

OBJECTIVES

We performed a systematic review and meta-analysis to understand the role of flow-mediated dilatation (FMD) of the brachial artery (BA) and peripheral arterial tonometry (PAT) in predicting adverse events, including cardiovascular (CV) events and all-cause mortality.

BACKGROUND

FMD of the BA and PAT are non-invasive measures of endothelial function. Impairment of endothelial function is associated with increased CV events. While FMD is the more widely used and studied technique, PAT offers several advantages. The purpose of this systematic review and meta-analysis is to determine whether brachial FMD and PAT are independent risk factors for future CV events and mortality.

METHODS

Multiple electronic databases were searched for articles relating FMD or PAT to CV events. Data were extracted on study characteristics, study quality, and study outcomes. Relative risks (RRs) from individual studies were combined and a pooled multivariate RR was calculated.

RESULTS

Thirty-six studies for FMD were included in the systematic review, of which 32 studies consisting of 15, 191 individuals were meta-analysed. The pooled RR of CV events and all-cause mortality per 1% increase in brachial FMD, adjusting for potential confounders, was 0.90 (0.88-0.92). In contrast, only three studies evaluated the prognostic value of PAT for CV events, and the pooled RR per 0.1 increase in reactive hyperaemia index was 0.85 (0.78-0.93).

CONCLUSION

Brachial FMD and PAT are independent predictors of CV events and all-cause mortality. Further research to evaluate the prognostic utility of PAT is necessary to compare it with FMD as a non-invasive endothelial function test in clinical practice.

High-efficiency on-line haemodiafiltration improves conduit artery endothelial function compared with high-flux haemodialysis in end-stage renal disease patients

BACKGROUND

Middle molecular weight uraemic toxins are considered to play an important role in vascular dysfunction and cardiovascular outcomes in end-stage renal disease (ESRD) patients. Recent dialysis techniques based on convection, specifically high-efficiency on-line haemodiafiltration (HDF), enhance the removal of middle molecular weight toxins and reduce all-cause mortality in haemodialysis (HD) patients. However, the mechanisms of these improved outcomes remain to be established.

METHODS

This prospective study randomly assigned 42 ESRD patients to switch from high-flux HD to high-efficiency on-line HDF (n=22) or to continue HD (n=20). Brachial artery endothelium-dependent flow-mediated dilatation, central pulse pressure, carotid artery intima-media thickness (IMT), internal diastolic diameter and distensibility and circulating markers of uraemia, inflammation and oxidative stress were blindly assessed before and after a 4-month follow-up.

RESULTS

Brachial flow-mediated dilatation and carotid artery distensibility increased significantly in the HDF group compared with HD, while carotid IMT and diameter remained similar. HDF decreased predialysis levels of the uraemic toxins β2-microglobulin, phosphate and blood TNFα mRNA expression. Oxidative stress markers were not different between the HD and HDF groups. Blood mRNA expression of protein kinase C β2, an endothelial NO-synthase (eNOS) inhibitor, decreased significantly with HDF.

CONCLUSIONS

High-efficiency on-line HDF prevents the endothelial dysfunction and stiffening of the conduit arteries in ESRD patients compared with high-flux HD. HDF decreases uraemic toxins, vascular inflammation, and is associated with subsequent improvement in eNOS functionality. These results suggest that reduced endothelial dysfunction may be an intermediate mechanism explaining the beneficial outcomes associated with HDF.

Intima-media thickness in severe obesity: links with BMI and metabolic status but not with systemic or adipose tissue inflammation

OBJECTIVE

Obesity is associated with cardiovascular risk and a low-grade inflammatory state in both blood and adipose tissue (AT). Whether inflammation contributes to vascular alteration remains an open question. To test this hypothesis, we measured arterial intima-media thickness (IMT), which reflects subclinical atherosclerosis, in severely obese subjects and explored associations with systemic inflammation and AT inflammation.

RESEARCH DESIGN AND METHODS

IMT of the carotid artery (C-IMT) and IMT of the femoral artery (F-IMT) were measured in 132 nonobese (control) subjects (BMI 22.3 kg/m2; mean age 44.8 years) and 232 subjects who were severely obese without diabetes (OB/ND; n = 146; BMI 48.3 kg/m2; age 38.2 years) or severely obese with type 2 diabetes (OB/D; n = 86; BMI 47.0; age 49.4 years). In 57 OB/ND subjects, circulating soluble E-selectin, matrix metalloproteinase 9, myeloperoxidase, soluble intracellular adhesion molecule 1, soluble vascular cell adhesion molecule 1, tissue plasminogen activator inhibitor 1, cystatin C, cathepsin S, and soluble CD14 were measured in serum. AT macrophages were quantified by CD68 immunochemistry.

RESULTS

Both C-IMT and F-IMT increased in OB/ND and OB/D patients. In OB/ND patients, age was the sole independent determinant of IMT. No significant association was found with circulating inflammation-related molecules, number of CD68+ cells, or the presence of crown-like structures in visceral or subcutaneous AT of OB/ND patients.

CONCLUSIONS

IMT increased with severe obesity but was not influenced by the degree of systemic inflammation or AT macrophage accumulation.

Carotid intima-media thickness testing as an asymptomatic cardiovascular disease identifier and method for making therapeutic decisions

Cardiovascular disease (CVD) is the leading cause of death and disability in the United States. Although current therapies can reduce the risk for CVD, they are only given to patients who are considered to be at risk, and are therefore only beneficial if a patient's risk is accurately predicted before he or she sustains a cardiovascular (CV) event. Unfortunately, even relatively accurate risk factor analyses, such as the Reynolds Risk Score algorithm, fail to identify some patients who will sustain a CV event within 10 years. In contrast, the presence of an atheroma is an absolute predictor for the potential of an atherothrombotic event to occur, and it is therefore reasonable to anchor clinical decisions based on this knowledge. Carotid intima-media thickness (CIMT) testing via B-mode ultrasound is a safe, simple, and inexpensive method for evaluating CV risk by measuring the combined thickness of the intimal and medial layers of the arterial wall. Use of CIMT testing can also detect marked thickening of the arterial wall, possibly indicating plaques or atheromas that are associated with accelerated atherosclerotic disease and increased risk for coronary artery disease, myocardial infarction, and stroke. These characteristics make CIMT a practical supplemental method that physicians can use when making decisions. Moreover, the ability of CIMT testing to identify and quantify atherosclerotic disease has led to the adoption of CIMT as a surrogate endpoint in clinical trials, allowing the efficacy of new drugs to be assessed much more rapidly than would be possible by focusing solely on CV event or mortality rates. To date, several trials have provided evidence to indicate that some CVD therapies slow, stop, or reverse the progression of CIMT. Although many of these studies show that changes in CIMT predict future CV events, the value of CIMT testing in CVD risk assessment is still vigorously debated. In this article, we clarify the utility of CIMT testing for risk classification and reexamine its usefulness as a method for assessing therapeutic efficacy.